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Additions to the NASA Aeronautics and Space Database as of 12/19/2011
20110023302 Washington Univ., Seattle, WA, United States
Global Variability of Mesoscale Convective System
Yuan, J.; Houze, R. A., Jr.; Journal of Climate; January 2010; vol. Volume 23; pp. 5864-588; In English
Contract(s)/Grant(s): NNX07AQ89G
Copyright; Availability: Other Sources
Mesoscale convective systems (MCSs) in the tropics produce extensive anvil clouds, which significantly affect the transfer of radiation. This study develops an objective method to identify MCSs and their anvils by combining data from three A-train satellite instruments: Moderate Resolution Imaging Spectroradiometer (MODIS) for cloud-top size and coldness, Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E) for rain area size and intensity, and CloudSat for horizontal and vertical dimensions of anvils. The authors distinguish three types of MCSs: small and large separated MCSs and connected MCSs. The latter are MCSs sharing a contiguous rain area. Mapping of the objectively identified MCSs shows patterns of MCSs that are consistent with previous studies of tropical convection, with separated MCSs dominant over Africa and the Amazon regions and connected MCSs favored over the warm pool of the Indian and west Pacific Oceans. By separating the anvil from the raining regions of MCSs, this study leads to quantitative global maps of anvil coverage. These maps are consistent with the MCS analysis, and they lay the foundation for estimating the global radiative effects of anvil clouds. CloudSat radar data show that the modal thickness of MCS anvils is about 4--5 km. Anvils are mostly confined to within 1.5--2 times the equivalent radii of the primary rain areas of the MCSs. Over the warm pool, they may extend out to about 5 times the rain area radii. The warm ocean MCSs tend to have thicker non-raining and lightly raining anvils near the edges of their actively raining regions, indicating that anvils are generated in and spread out from the primary raining regions of the MCSs. Thicker anvils are nearly absent over continental regions.
Author
ANVIL CLOUDS; CONVECTION; MESOSCALE PHENOMENA; RAIN; TROPICAL REGIONS; TROPICAL METEOROLOGY; PRECIPITATION (METEOROLOGY)
20110023303 Washington Univ., Seattle, WA, United States
Vertical Structures of Anvil Clouds of Tropical Mesoscale Convective Systems Observed by CloudSat
Yuan, J.; Houze, R. A., Jr.; Heymsfield, A.; Journal of the Atmospheric Sciences; August 2011; vol. Volume 68; issue No. 8; pp. 1653-167; In English
Contract(s)/Grant(s): NNX07AQ89G
Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1175/2011JAS3687.1
A global study of the vertical structures of the clouds of tropical mesoscale convective systems (MCSs) has been carried out with data from the CloudSat Cloud Profiling Radar. Tropical MCSs are found to be dominated by cloud-top heights greater than 10 km. Secondary cloud layers sometimes occur in MCSs, but outside their primary raining cores. The secondary layers have tops at 6--8 and 1--3 km. High-topped clouds extend outward from raining cores of MCSs to form anvil clouds. Closest to the raining cores, the anvils tend to have broader distributions of reflectivity at all levels, with the modal values at higher reflectivity in their lower levels. Portions of anvil clouds far away from the raining core are thin and have narrow frequency distributions of reflectivity at all levels with overall weaker values. This difference likely reflects ice particle fallout and therefore cloud age. Reflectivity histograms of MCS anvil clouds vary little across the tropics, except that (i) in continental MCS anvils, broader distributions of reflectivity occur at the uppermost levels in the portions closest to active raining areas; (ii) the frequency of occurrence of stronger reflectivity in the upper part of anvils decreases faster with increasing distance in continental MCSs; and (iii) narrower-peaked ridges are prominent in reflectivity histograms of thick anvil clouds close to the raining areas of connected MCSs (superclusters). These global results are consistent with observations at ground sites and aircraft data. They present a comprehensive test dataset for models aiming to simulate process-based upper-level cloud structure around the tropics.
Author
ANVIL CLOUDS; CLOUD PHYSICS; MESOSCALE PHENOMENA; TROPICAL REGIONS; TROPICAL METEOROLOGY; SATELLITE OBSERVATION
20110023307 NASA Goddard Space Flight Center, Greenbelt, MD, United States
HIWRAP Radar Development for High-Altitude Operation on the NASA Global Hawk and ER-2
Li, Lihua; Heymsfield, Gerlad; Careswell, James; Schaubert, Dan; Creticos, Justin; September 26, 2011; In English; 35th Conference on Radar Meteorology, American Meteorological Society, 26-30 Sep. 2011, Pittsburgh, PA, United States
Report No.(s): GSFC.ABS.5110.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023307
The NASA High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP) is a solid-state transmitter-based, dual-frequency (Ka- and Ku-band), dual-beam (30 degree and 40 degree incidence angle), conical scan Doppler radar system, designed for operation on the NASA high-altitude (20 km) aircrafts, such as the Global Hawk Unmanned Aerial System (UAS). Supported by the NASA Instrument Incubator Program (IIP), HIWRAP was developed to provide high spatial and temporal resolution 3D wind and reflectivity data for the research of tropical cyclone and severe storms. With the simultaneous measurements at both Ku- and Ka-band two different incidence angles, HIWRAP is capable of imaging Doppler winds and volume backscattering from clouds and precipitation associated with tropical storms. In addition, HIWRAP is able to obtain ocean surface backscatter measurements for surface wind retrieval using an approach similar to QuikScat. There are three key technology advances for HIWRAP. Firstly, a compact dual-frequency, dual-beam conical scan antenna system was designed to fit the tight size and weight constraints of the aircraft platform. Secondly, The use of solid state transmitters along with a novel transmit waveform and pulse compression scheme has resulted in a system with improved performance to size, weight, and power ratios compared to typical tube based Doppler radars currently in use for clouds and precipitation measurements. Tube based radars require high voltage power supply and pressurization of the transmitter and radar front end that complicates system design and implementation. Solid state technology also significantly improves system reliability. Finally, HIWRAP technology advances also include the development of a high-speed digital receiver and processor to handle the complex receiving pulse sequences and high data rates resulting from multi receiver channels and conical scanning. This paper describes HIWRAP technology development for dual-frequency operation at high-altitudes using low peak power transmitters and pulse compression. The hardware will be described along with the methods and concepts for the system design. Finally, we will present recent preliminary results from flights on the NASA Global Hawk in support of the NASA Genesis and Rapid Intensification Processes (GRIP) field campaign, and on the NASA ER-2 as fixed nadir pointing mode for the NASA Global Precipitation Measurement (GPM) ground validation (GV) mission - Midlatitude Continental Convective Cloud Experiment (MC3E)
Author
HIGH ALTITUDE; IMAGING TECHNIQUES; RAIN; WIND PROFILES; PILOTLESS AIRCRAFT; DOPPLER RADAR
20110023308 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Experiments in Reconstructing Twentieth-Century Sea Levels
Ray, Richard D.; Douglas, Bruce C.; July 18, 2011; In English
Report No.(s): GSFC.ABS.5116.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023308
One approach to reconstructing historical sea level from the relatively sparse tide-gauge network is to employ Empirical Orthogonal Functions (EOFs) as interpolatory spatial basis functions. The EOFs are determined from independent global data, generally sea-surface heights from either satellite altimetry or a numerical ocean model. The problem is revisited here for sea level since 1900. A new approach to handling the tide-gauge datum problem by direct solution offers possible advantages over the method of integrating sea-level differences, with the potential of eventually adjusting datums into the global terrestrial reference frame. The resulting time series of global mean sea levels appears fairly insensitive to the adopted set of EOFs. In contrast, charts of regional sea level anomalies and trends are very sensitive to the adopted set of EOFs, especially for the sparser network of gauges in the early 20th century. The reconstructions appear especially suspect before 1950 in the tropical Pacific. While this limits some applications of the sea-level reconstructions, the sensitivity does appear adequately captured by formal uncertainties. All our solutions show regional trends over the past five decades to be fairly uniform throughout the global ocean, in contrast to trends observed over the shorter altimeter era. Consistent with several previous estimates, the global sea-level rise since 1900 is 1.70 +/- 0.26 mm/yr. The global trend since 1995 exceeds 3 mm/yr which is consistent with altimeter measurements, but this large trend was possibly also reached between 1935 and 1950.
Author
ANOMALIES; MATHEMATICAL MODELS; OCEAN SURFACE; OCEANS; SEA LEVEL
20110023309 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Observational Diagnoses of Extratropical Ozone STE During the Aura Era
Olsen, Mark A.; Douglass, Anne R.; Witte, Jacquie C.; Kaplan, Trevor B.; December 05, 2011; In English; 2011 Fall AGU Meeting, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): GSFC.ABS.5211.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023309
The transport of ozone from the stratosphere to the extratropical troposphere is an important boundary condition to tropospheric chemistry. However, previous direct estimates from models and indirect estimates from observations have poorly constrained the magnitude of ozone stratosphere-troposphere exchange (STE). In this study we provide a direct diagnosis of the extratropical ozone STE using data from the Microwave Limb Sounder on Aura and output of the MERRA reanalysis over the time period from 2005 to the present. We find that the mean annual STE is about 275 Tg/yr and 205 Tg/yr in the NH and SH, respectively. The interannual variability of the magnitude is about twice as great in the NH than the SH. We find that this variability is dominated by the seasonal variability during the late winter and spring. A comparison of the ozone flux to the mass flux reveals that there is not a simple relationship between the two quantities. This presentation will also examine the magnitude and distribution of ozone in the lower stratosphere relative to the years of maximum and minimum ozone STE. Finally, we will examine any possible signature of increased ozone STE in the troposphere using sonde and tropospheric ozone residual (TOR) data, and output from the Global Modeling Initiative Chemistry Transport Model (GMI CTM).
Author
ATMOSPHERIC CHEMISTRY; ATMOSPHERIC CIRCULATION; GAS TRANSPORT; OZONE; STRATOSPHERE; TROPOSPHERE
20110023310 NASA Goddard Space Flight Center, Greenbelt, MD, United States
DoD-GEIS Rift Valley Fever Monitoring and Prediction System as a Tool for Defense and US Diplomacy
Anyamba, Assaf; Tucker, Compton J.; Linthicum, Kenneth J.; Witt, Clara J.; Gaydos, Joel C.; Russell, Kevin L.; June 13, 2011; In English; 2011 USEUCOM and USAFRICOM Science and Technology Conference, 13-16 Jun. 2011, Stuttgart, Germany
Report No.(s): GSFC.ABS.5335.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023310
Over the last 10 years the Armed Forces Health Surveillance Center's Global Emerging Infections Surveillance and Response System (GEIS) partnering with NASA'S Goddard Space Flight Center and USDA's USDA-Center for Medical, Agricultural & Veterinary Entomology established and have operated the Rift Valley fever Monitoring and Prediction System to monitor, predict and assess the risk of Rift Valley fever outbreaks and other vector-borne diseases over Africa and the Middle East. This system is built on legacy DoD basic research conducted by Walter Reed Army Institute of Research overseas laboratory (US Army Medical Research Unit-Kenya) and the operational satellite environmental monitoring by NASA GSFC. Over the last 10 years of operation the system has predicted outbreaks of Rift Valley fever in the Horn of Africa, Sudan, South Africa and Mauritania. The ability to predict an outbreak several months before it occurs provides early warning to protect deployed forces, enhance public health in concerned countries and is a valuable tool use.d by the State Department in US Diplomacy. At the international level the system has been used by the Food and Agricultural Organization (FAD) and the World Health Organization (WHO) to support their monitoring, surveillance and response programs in the livestock sector and human health. This project is a successful testament of leveraging resources of different federal agencies to achieve objectives of force health protection, health and diplomacy.
Author
ENTOMOLOGY; HEALTH; INFECTIOUS DISEASES; MEDICAL SCIENCE; PREDICTION ANALYSIS TECHNIQUES; SATELLITE OBSERVATION
20110023311 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Preliminary Analysis of Images from the Thermospheric Temperature Image on Fast, Affordable, Science and Technology Satellite (FASTSAT)
Rodriquez, Marcello; Jones, Sarah; Mentzell, Eric; Gill, Nathaniel; December 05, 2011; In English; 2-11 American Geophysical Union meeting, 5-9 Dec. 2011, San Francisco,CA, United States
Report No.(s): GSFC.ABS.5337.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023311
The Thermospheric Temperature Imager (TTI) on Fast, Affordable, Science and Technology SATellite (FASTSAT) measures the upper atmospheric atomic oxygen emission at 135.6 nm and the molecular nitrogen LBH emission at 135.4 nm to determine the atmospheric O/N2 density ratio. Observations of variations in this thermospheric ratio correspond to electron density variations in the ionosphere. The TTI design makes use of a Fabry-Perot interferometer to measure Doppler widened atmospheric emissions to determine neutral atmospheric temperature from low Earth orbit. FASTSAT launched November 10, 2010 and TTI is currently observing geomagnetic signatures in the aurora and airglow. This work is supported by NASA.
Author
ATMOSPHERIC TEMPERATURE; ELECTRON DENSITY (CONCENTRATION); THERMOSPHERE; SATELLITE TEMPERATURE; OXYGEN ATOMS; ATMOSPHERIC DENSITY; AURORAS; GEOMAGNETISM
20110023312 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Auroral Current and Electrodynamics Structure (ACES) Observations of Ionospheric Feedback in the Alfven Resonator
Cohen, Ian J.; Lessard, Marc; Lund, Eric J.; Bounds, Scott R.; Kletzing, Craig; Kaeppler, Stephen R.; Sigsbee, Kristine M.; Streltsov, Anatoly V.; Labelle, James W.; Dombrowski, Micah P.; Pfaff, Robert F.; Rowland, Doug; Jones, Sarah; Anderson, Brian Jay; Heinselman, Craig J.; Gjerloev, Jesper W.; Dudok de Wit, Thierry; December 05, 2011; In English; 2011 Fall American Geophysical Union, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): GSFC.ABS.5338.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023312
In 2009, the Auroral Current and Electrodynamics Structure (ACES) High and Low sounding rockets were launched from the Poker Flat Rocket Range (PFRR) in Alaska, with the science objective of gathering in-situ data to quantify current closure in a discrete auroral arc. As ACES High crossed through the return current of an arc (that was monitored using an all sky camera from the ground at Fort Yukon), its instruments recorded clear Alfv nic signatures both poleward and equatorward of the return current region, but not within the main region of the return current itself. These data provide an excellent opportunity to study ionospheric feedback and how it interacts with the Alfv n resonator. We compare the observations with predictions and new results from a model of ionospheric feedback in the ionospheric Alfv n resonator (IAR) and report the significance and impact of these new data for the Magnetosphere-Ionosphere Coupling in the Alfv n Resonator (MICA) rocket mission to launch from PFRR this winter. MICA s primary science objectives specifically focus on better understanding the small-scale structure that the model predicts should exist within the return current region.
Author
AURORAL ARCS; SOUNDING ROCKETS; MAGNETOHYDRODYNAMIC WAVES; MAGNETOSPHERE-IONOSPHERE COUPLING; ELECTRODYNAMICS; AURORAS
20110023313 Jet Propulsion Lab., California Inst. of Tech., Pasadena, CA, United States
New Challenges of Cloud Remote Sensing from Space
Wu, Dong L.; [2011]; In English
Report No.(s): GSFC.ABS.5342.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023313
Clouds are recognized as a major source of uncertainties in predicting climate change. Lack of observational constraints on cloud processes has hindered the development of more reliable climate and weather models. With the advanced NASA EOS and A-Train sensors, we now have better knowledge about vertical distribution, water content, and occurrence frequency of global cloudiness. New ice water content (IWC) measurements from CloudSat and MLS have led to several improvements in model physics and parameterization schemes. MISR and GPS high-resolution data start to reveal deep insights on cloud processes and dynamicS in the planetary boundary layer (PBL). However, Earth sciences are still facing urgent needs to measure cloud microphysical properties, interactions between clouds and aerosol/precipitation, and processes that are coupled in 3-D space but not adequately sampled by the A-Train curtains or by the 2-D imageries. Submillimeter- wave, multi-angle imaging, and GPS radio occultation have emerged as promising remote sensing techniques to meet the challenges and enable new sciences for mid-tropospheric and PBL clouds.
Author
CLIMATE CHANGE; CLOUD PHYSICS; HIGH RESOLUTION; VERTICAL DISTRIBUTION; REMOTE SENSING; MOISTURE CONTENT; MISR (RADIOMETRY); IMAGING TECHNIQUES; AEROSOLS; CLOUD COVER
20110023314 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Aerosol Constraints from Multi-Angle Imaging That Modelers Can Use
Kahn, Ralph; October 03, 2011; In English; 10th AeroCom Workshop, 3-6 Oct. 2011, Fukuoka, Japan
Report No.(s): GSFC.ABS.5343.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023314
As we continue to develop, refine, and apply the MISR aerosol products to a range of scientific questions, the strengths and limitations of the data content regarding aerosol optical depth (AOD), aerosol type, and plume height mapping have become pretty clear. Optimizing the operational algorithms to take advantage of the multi-angle, multi-spectral radiance information content is challenging in some situations, so we have also developed a number of specialized tools that run only on individual cases. These include the MISR Research Aerosol Retrieval algorithm, the highest-quality aerosol plume heights derived from the MINX software, and MISR-MODIS aerosol transport mapping code. This presentation will focus on some of the research products we are creating, with emphasis on those that might be most useful for constraining aerosol transport models, As we have acquired more than 11 years of once-weekly global coverage from MISR, discussion with the group will consider where and when having these products would maximize our contribution to AeroCom modeling efforts, in the context of practical limitations on specialized product generation.
Author
AEROSOLS; IMAGING TECHNIQUES; MISR (RADIOMETRY); OPTICAL THICKNESS; MODIS (RADIOMETRY); ATMOSPHERIC MODELS
20110023315 NASA Goddard Space Flight Center, Greenbelt, MD, United States
What Good is Raman Water Vapor Lidar?
Whitman, David; September 22, 2011; In English; Latin American Lidar Workshop, 22 Sep. - 4 Oct. 2011, La Paz, Bolivia
Report No.(s): GSFC.ABS.5344.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023315
Raman lidar has been used to quantify water vapor in the atmosphere for various scientific studies including mesoscale meteorology and satellite validation. Now the international networks of NDACC and GRUAN have interest in using Raman water vapor lidar for detecting trends in atmospheric water vapor concentrations. What are the data needs for addressing these very different measurement challenges. We will review briefly the scientific needs for water vapor accuracy for each of these three applications and attempt to translate that into performance specifications for Raman lidar in an effort to address the question in the title of "What good is Raman water vapor Iidar."
Author
MESOMETEOROLOGY; OPTICAL RADAR; WATER VAPOR; RAMAN SPECTRA; MESOSCALE PHENOMENA
20110023316 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Design of Spacecraft Missions to Test Kinetic Impact for Asteroid Deflection
Hernandez, Sonia; Barbee, Brent W.; [2011]; In English; 22nd AAS Space Flight Mechanics Meeting, 29 Jan. - 2 Feb. 2012, Charleston, SC, United States; Original contains color illustrations
Report No.(s): GSFC.ABS.5349.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023316
There are currently over 8,000 known near-Earth asteroids (NEAs), and more are being discovered on a continual basis. More than 1,200 of these are classified as Potentially Hazardous Asteroids (PHAs) because their Minimum Orbit Intersection Distance (MOID) with Earth's orbit is <= 0.05 AU and their estimated diameters are >= 150 m. To date, 178 Earth impact structures have been discovered, indicating that our planet has previously been struck with devastating force by NEAs and will be struck again. Such collisions are aperiodic events and can occur at any time. A variety of techniques have been proposed to defend our planet from NEA impacts by deflecting the incoming asteroid. However, none of these techniques have been tested. Unless rigorous testing is conducted to produce reliable asteroid deflection systems, we will be forced to deploy completely untested -- and therefore unreliable -- deflection missions when a sizable asteroid on a collision course with Earth is discovered. Such missions will have a high probability of failure. We propose to address this problem with a campaign of deflection technology test missions deployed to harmless NEAs. The objective of these missions is to safely evaluate and refine the mission concepts and asteroid deflection system designs. Our current research focuses on the kinetic impactor, one of the simplest proposed asteroid deflection techniques in which a spacecraft is sent to collide with an asteroid at high relative velocity. By deploying test missions in the near future, we can characterize the performance of this deflection technique and resolve any problems inherent to its execution before needing to rely upon it during a true emergency. In this paper we present the methodology and results of our survey, including lists of NEAs for which safe and effective kinetic impactor test missions may be conducted within the next decade. Full mission designs are also presented for the NEAs which offer the best mission opportunities.
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ASTEROID COLLISIONS; ASTEROIDS; DEFLECTION; MISSION PLANNING; NEAR EARTH OBJECTS
20110023317 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Land Data Assimilation of Satellite-Based Soil Moisture Products Using the Land Information System Over the NLDAS Domain
Mocko, David M.; Kumar, S. V.; Peters-Lidard, C. D.; Tian, Y.; [2011]; In English; 92nd American Meteorological Society Meeting, 22-26 Jan. 2012, New Orleans, LA, United States
Report No.(s): GSFC.ABS.5355.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023317
This presentation will include results from data assimilation simulations using the NASA-developed Land Information System (LIS). Using the ensemble Kalman filter in LIS, two satellite-based soil moisture products from the AMSR-E instrument were assimilated, one a NASA-based product and the other from the Land Parameter Retrieval Model (LPRM). The domain and land-surface forcing data from these simulations were from the North American Land Data Assimilation System Phase-2, over the period 2002-2008. The Noah land-surface model, version 3.2, was used during the simulations. Changes to estimates of land surface states, such as soil moisture, as well as changes to simulated runoff/streamflow will be presented. Comparisons over the NLDAS domain will also be made to two global reference evapotranspiration (ET) products, one an interpolated product based on FLUXNET tower data and the other a satellite- based algorithm from the MODIS instrument. Results of an improvement metric show that assimilating the LPRM product improved simulated ET estimates while the NASA-based soil moisture product did not.
Author
INFORMATION SYSTEMS; LAND MANAGEMENT; SOIL MOISTURE; DATA ACQUISITION; MODIS (RADIOMETRY); EARTH SURFACE
20110023318 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Preflight Calibration of the Thermal Infrared Sensor (TIRS) on the Landsat Data Continuity Mission
Smith, Ramsey; Reuter, Dennis; Irons, James; Lunsford, Allen; Montanero, Matthew; Tesfaye, Zelalem; Wenny, Brian; Thome, Kurtis; November 14, 2011; In English; PECORA 18 Symposium, 14-17 Nov. 2011, Herndon, VA, United States
Report No.(s): GSFC.ABS.5359.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023318
The preflight calibration testing of TIRS evaluates the performance of the instrument at the component, subsystem and system level, The overall objective is to provide an instrument that is well calibrated and well characterized with specification compliant data that will ensure the data continuity of Landsat from the previous missions to the LDCM, The TIRS flight build unit and the flight instrument were assessed through a series of calibration tests at NASA Goddard Space Flight Center. Instrument-level requirements played a strong role in defining the test equipment and procedures used for the calibration in the thermal/vacuum chamber. The calibration ground support equipment (CGSE), manufactured by MEI and ATK Corporation, was used to measure the optical, radiometric and geometric characteristics of TIRS, The CGSE operates in three test configurations: GeoRad (geometric, radiometric and spatial), flood source and spectral, TIRS was evaluated though the following tests: bright target recovery, radiometry, spectral response, spatial shape, scatter, stray light, focus, and uniformity, Data were obtained for the instrument and various subsystems under conditions simulating those on orbit In the spectral configuration, a monochromator system with a blackbody source is used for in-band and out-of-band relative spectral response characterization, In the flood source configuration the entire focal plane array is illuminated simultaneously to investigate pixel-to-pixel uniformity and dead or inoperable pixels, The remaining tests were executed in the GeoRad configuration and use a NIST calibrated cavity blackbody source, The NIST calibration is transferred to the TIRS sensor and to the blackbody source on-board TIRS, The onboard calibrator will be the primary calibration source for the TIRS sensor on orbit.
Author
CALIBRATING; INFRARED DETECTORS; LANDSAT SATELLITES; SATELLITE IMAGERY; REMOTE SENSING
20110023319 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Obscured AGN
Ptak, Andrew; September 13, 2011; In English; First eROSITA International Conference, 17-20 Oct. 2011, Garmisch-Partenkirchen, Germany
Report No.(s): GSFC.ABS.5360.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023319
Many obscured AGN show evidence of significant starburst emission dominating below 2 keV. Therefore wide-field X-ray surveys sensitive enough to luminosities below approximately 10^42 ergs per second will result in detections of galaxies with contributions of both obscured AGN and starburst emission. We will discuss Bayesian approaches to assessing the relative contribution of each component, minimizing survey biases and using the resultant posterior probabilities for the AGN and starburst components to determine their evolution.
Author
ACTIVE GALACTIC NUCLEI; STARBURST GALAXIES; LUMINOSITY; OCCULTATION
20110023320 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Space Weathering of Rocks
Noble, Sarah; October 09, 2011; In English; 2011 Geological Society of America (GSA) Annual Meeting and Exposition, 9-12 Oct. 2011, Minnwapolis, MN, FROM
Report No.(s): GSFC.ABS.5364.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023320
Space weathering discussions have generally centered around soils but exposed rocks will also incur the effects of weathering. On the Moon, rocks make up only a very small percentage of the exposed surface and areas where rocks are exposed, like central peaks, are often among the least space weathered regions we find in remote sensing data. However, our studies of weathered Ap 17 rocks 76015 and 76237 show that significant amounts of weathering products can build up on rock surfaces. Because rocks have much longer surface lifetimes than an individual soil grain, and thus record a longer history of exposure, we can study these products to gain a deeper perspective on the weathering process and better assess the relative impo!1ance of various weathering components on the Moon. In contrast to the lunar case, on small asteroids, like Itokowa, rocks make up a large fraction of the exposed surface. Results from the Hayabusa spacecraft at Itokowa suggest that while the low gravity does not allow for the development of a mature regolith, weathering patinas can and do develop on rock surfaces, in fact, the rocky surfaces were seen to be darker and appear spectrally more weathered than regions with finer materials. To explore how weathering of asteroidal rocks may differ from lunar, a set of ordinary chondrite meteorites (H, L, and LL) which have been subjected to artificial space weathering by nanopulse laser were examined by TEM. NpFe(sup 0) bearing glasses were ubiquitous in both the naturally-weathered lunar and the artificially-weathered meteorite samples.
Author
ASTEROIDS; LUNAR ROCKS; SPACE WEATHERING; LUNAR MARIA; SELENOLOGY
20110023321 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Multi-Decadal Change of Atmospheric Aerosols and their Effect on Surface Radiation
Chin, Mian; Diehl, Thomas; Streets, David; Wild, Martin; Qian, Yun; Yu, Hongbin; Tan, Qian; Bian, Huisheng; Wang, Weiguo; October 03, 2011; In English; 10th AeroCom Workshop, 3-6 Oct. 2011, Fukuoka, Japan
Report No.(s): GSFC.ABS.5365.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023321
We present an investigation on multi-decadal changes of atmospheric aerosols and their effects on surface radiation using a global chemistry transport model, GOCART, along with the near-term to long-term data records. We focus on a 28-year time period of satellite era from 1980 to 2007 during which a suite of aerosol data from satellite observations, ground-based measurements, and intensive field experiments have become available. Particularly: (1) We compare the model calculated clear sky downward radiation at the surface with surface network data from BSRN and CMA (2) We compare the model and surface data with satellite derived downward radiation products from ISCCP and SRS (3) We analyze the long-term global and regional aerosol trends in major anthropogenic source regions (North America, Europe, Asia) that have been experiencing considerable changes of emissions during the three decades, dust and biomass burning regions that have large interannual variability, downwind regions that are directly affected by the changes in the source area, and remote regions that are considered to representing "background" conditions. The comparisons and methods from this study can be applied to multiple model analysis in the AeroCom framework.
Author
AEROSOLS; PERIODIC VARIATIONS; SATELLITE OBSERVATION; EARTH SURFACE; ATMOSPHERIC MODELS; TERRESTRIAL RADIATION
20110023322 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The MODIS Aerosol Algorithms: Past, Present, Future
Remer, Lorraine; September 11, 2011; In English; Observational and Modeling of Aerosol and Clouds Properties for Climate Studies Workshop, 11-14 Sep. 2011, Paris, France
Report No.(s): GSFC.ABS.5366.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023322
The MODIS aerosol products today are widely used by the climate and air quality communities, operationally in data assimilation systems, by air quality forecasters, and throughout the research world. The product is the result of algorithms that were conceptualized 20 years ago by Yoram Kaufman and Didier Tanre, developed through the entire 1990's by a team spanning two continents, and maintained and evaluated since Terra launch in 1999. I will use this opportunity to point out the highlights of the past 20 years, and preview plans for a future that is beginning even now.
Author
AEROSOLS; ALGORITHMS; MODIS (RADIOMETRY); CLIMATOLOGY; AIR QUALITY
20110023323 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Advancing Solar Irradiance Measurement for Climate-Related Studies: Accurate Constraint on Direct Aerosol Radiative Effect (DARE)
Tsay, Si-Chee; Ji, Q. Jack; October 03, 2011; In English; 10th AeroComp Workshop, 3-6 Oct. 2011, Fukuoka, Japan
Report No.(s): GSFC.ABS.5367.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023323
Earth's climate is driven primarily by solar radiation. As summarized in various IPCC reports, the global average of radiative forcing for different agents and mechanisms, such as aerosols or CO2 doubling, is in the range of a few W/sq m. However, when solar irradiance is measured by broadband radiometers, such as the fleet of Eppley Precision Solar Pyranometers (PSP) and equivalent instrumentation employed worldwide, the measurement uncertainty is larger than 2% (e.g., WMO specification of pyranometer, 2008). Thus, out of the approx. 184 W/sq m (approx.263 W/sq m if cloud-free) surface solar insolation (Trenberth et al. 2009), the measurement uncertainty is greater than +/-3.6 W/sq m, overwhelming the climate change signals. To discern these signals, less than a 1 % measurement uncertainty is required and is currently achievable only by means of a newly developed methodology employing a modified PSP-like pyranometer and an updated calibration equation to account for its thermal effects (li and Tsay, 2010). In this talk, we will show that some auxiliary measurements, such as those from a collocated pyrgeometer or air temperature sensors, can help correct historical datasets. Additionally, we will also demonstrate that a pyrheliometer is not free of the thermal effect; therefore, comparing to a high cost yet still not thermal-effect-free "direct + diffuse" approach in measuring surface solar irradiance, our new method is more economical, and more likely to be suitable for correcting a wide variety of historical datasets. Modeling simulations will be presented that a corrected solar irradiance measurement has a significant impact on aerosol forcing, and thus plays an important role in climate studies.
Author
SOLAR RADIATION; CLIMATE CHANGE; TEMPERATURE EFFECTS; TERRESTRIAL RADIATION; CALIBRATING; CARBON DIOXIDE; PYRANOMETERS; RADIATIVE FORCING; CLIMATE
20110023324 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Toward a Coherent Detailed Evaluation of Aerosol Data Products from Multiple Satellite Sensors
Ichoku, Charles; Petrenko, Maksym; Leptoukh, Gregory; September 12, 2011; In English
Report No.(s): GSFC.ABS.5368.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023324
Atmospheric aerosols represent one of the greatest uncertainties in climate research. Although satellite-based aerosol retrieval has practically become routine, especially during the last decade, there is often disagreement between similar aerosol parameters retrieved from different sensors, leaving users confused as to which sensors to trust for answering important science questions about the distribution, properties, and impacts of aerosols. As long as there is no consensus and the inconsistencies are not well characterized and understood, there will be no way of developing reliable climate data records from satellite aerosol measurements. Fortunately, the most globally representative well-calibrated ground-based aerosol measurements corresponding to the satellite-retrieved products are available from the Aerosol Robotic Network (AERONET). To adequately utilize the advantages offered by this vital resource, an online Multi-sensor Aerosol Products Sampling System (MAPSS) was recently developed. The aim of MAPSS is to facilitate detailed comparative analysis of satellite aerosol measurements from different sensors (Terra-MODIS, Aqua-MODIS, TerraMISR, Aura-OMI, Parasol-POLDER, and Calipso-CALIOP) based on the collocation of these data products over AERONET stations. In this presentation, we will describe the strategy of the MA~SS system, its potential advantages for the aerosol community, and the preliminary results of an integrated comparative uncertainly analysis of aerosol products from multiple satellite sensors.
Author
AEROSOLS; AQUA SPACECRAFT; TERRA SPACECRAFT; SATELLITE INSTRUMENTS; SATELLITE OBSERVATION; CALIBRATING; AIR SAMPLING; CLIMATE
20110023325 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Aerosol Comparisons Between Observations and Models: AeroCom and ABC
Chin, Mian; Schulz, Michael; Kinne, Stefan; [2011]; In English
Report No.(s): GSFC.ABS.5370.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023325
I will represent the AeroCom community to the Atmospheric Brown Cloud (ABC) workshop. I will summarize the activities and results from AeroCom Phase I activities in the past 8 years and introduce the new results and activities in the current AeroCom Phase II. We hope to coordinate some activities with the ABC community to share model output and data access for model evaluations, comparisons, and assessment.
Author
AEROSOLS; ATMOSPHERIC MODELS; OBSERVATION; COMPARISON
20110023326 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Submm-Wave Radiometry for Cloud/Humidity/Precipitation Sciences
Wu, Dong L.; September 22, 2011; In English; 2011 Atmospheric Submillimetre Workshop, 22-23 Sep. 2011, Exeter, United Kingdom
Report No.(s): GSFC.ABS.5371.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023326
Although active sensors can provide cloud profiles at good vertical resolution, clouds are often coupled with dynamics to form fast and organized structures. Lack of understanding of these organized systems leads to great challenge for numerical models. The deficiency is partly reflected, for example, in poorly modeled intraseasonal variations (e.g., MJD). Remote sensing clouds in the middle and upper troposphere has been challenging from space. Vis/IR sensors are sensitive to the topmost cloud layers whereas low-frequency MW techniques are sensitivity to liquid and precipitation at the bottom of cloud layers. The middle-level clouds, mostly in the ice phase, require a sensor that has moderate penetration and sensitivity to cloud scattering, in order to measure cloud water content. Sensors at submm wavelengths provide promising sensitivity and coverage with the spatial resolution needed to measure cloud water content floating in the upper air. In addition, submm-wave sensors are able to provide better measurements of upper-tropospheric humidity than traditional microwave instruments.
Author
SUBMILLIMETER WAVES; CLOUD COVER; HUMIDITY; MOISTURE CONTENT; SPATIAL RESOLUTION; MICROWAVE SENSORS; INTRASEASONAL VARIATIONS; REMOTE SENSING; CLOUD-TO-CLOUD DISCHARGES
20110023327 NASA Goddard Space Flight Center, Greenbelt, MD, United States
October Cloud Increases Over the Arctic Ocean as Observed by MISR and CALIPSO
Wu, Dong L.; Lee, Jae N.; September 25, 2011; In English; 2011 International Arctic Scientific Science Committee (IASC) Atmosphere Working Group Workshop on Arctic Measurements, 26-27 Sep. 2011, Potsdam, Germany
Report No.(s): GSFC.ABS.5372.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023327
The Beaufort and East Siberian Sea (BESS) shows a large increase in surface air temperature (SAT) in the recent decade for months of Sep-Nov, and NASA's Terra satellite have provided valuable measurements for this important decade of the intensified Arctic warming. In particular, MISR data since 2000 and CALIPSO cloud measurements since 2006 reveal a significant increase of low cloud cover in October, which is largest in the daylight Arctic months (March-October). Causes of the warming remain unclear; but increased absorption of summer solar radiation and autumn low cloud formation have been suggested as a positive ice-temperature-cloud feedback in the Arctic. The observed increase of low cloud cover supports the theorized positive ice-temperature-cloud feedback, whereby more open water in the Arctic Ocean increases summer absorption of solar radiation, and subsequent evaporation, which leads to more low clouds in autumn. Trapping longwave radiation, these clouds effectively lengthen the melt season and reduce perennial ice pack formation, making sea ice more vulnerable to the next melt season
Author
ARCTIC OCEAN; CLOUD COVER; ICE CLOUDS; ATMOSPHERIC TEMPERATURE; SURFACE TEMPERATURE; OCEAN SURFACE; RADIATION ABSORPTION; SEA ICE
20110023328 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The James Webb Space Telescope: Science and Mission Status
Sonneborn, George; October 17, 2011; In English; Middlebury College Colloquium, 17 Oct. 2011, Middleburgy, VT, United States
Report No.(s): GSFC.ABS.5430.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023328
The James Webb Space Telescope (JWST) is a large aperture, cryogenic, infrared-optimized space observatory under construction by NASA for launch later this decade. The European and Canadian Space Agencies are mission partners. JWST will find and study the first galaxies that formed in the early universe and peer through dusty clouds to see star and planet formation at high spatial resolution. The breakthrough capabilities of JWST will enable new studies of star formation and evolution in the Milky Way, including the Galactic Center, nearby galaxies, and the early universe. JWST will have a segmented primary mirror, approximately 6.5 meters in diameter, and will be diffraction-limited at 2 microns. The JWST observatory will be placed in a L2 orbit by an Ariane 5 launch vehicle provided by ESA. The observatory is designed for a 5- year prime science mission, with consumables for 10 years of science operations.
Author
JAMES WEBB SPACE TELESCOPE; INFRARED ASTRONOMY; SPACEBORNE ASTRONOMY; UNIVERSE; COSMOLOGY; SEGMENTED MIRRORS
20110023329 NASA Goddard Space Flight Center, Greenbelt, MD, United States
How To Get a Job Working for NASA
Gardner, Jonathan; November 15, 2011; In English
Report No.(s): GSFC.ABS.5431.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023329
In an informal meeting with students, I will give an overview of NASA and discuss who works for NASA: astronauts, scientists, engineers, managers and secretaries, and how they are selected, hired and employed. I will discuss the process for applying for NASA jobs, including student programs.
Author
STUDENTS; PERSONNEL; SCIENTISTS; EMPLOYMENT; ASTRONAUTS; OCCUPATION; WORK
20110023331 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Beginning and End of the Universe
Gardner, Jonathan P.; November 15, 2011; In English
Report No.(s): GSFC.ABS.5435.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023331
Cosmology is the scientific study of how the Universe began more than 13 billion years ago, how its properties have changed from that time to the present, and what its eventual fate might be. Observational cosmology uses telescopes like the Hubble to reach back in time to find the faint echoes of the Big Bang. In this lecture, I will give an overview of cosmology, highlighting the very rapid progress this field has made in the last decade, and the role that NASA space telescopes have played and will continue to play in the years to come. I will then focus on two of the most intriguing of those recent discoveries: inflation and dark energy. Our universe began in an extremely rapid accelerated expansion, called inflation, which removed all traces anything that may have existed before, flattened the geometry of space-time, and turned microscopic quantum fluctuations into the largest structures in the universe. At the present time, more than 70% of the mass-energy in the Universe consists of a mysterious substance called dark energy. The dark energy causes the expansion of the Universe to accelerate, and he will discuss the ways that we might be able to measure that acceleration more accurately, revealing the nature of the dark energy and learning the eventual fate of the Universe.
Author
COSMOLOGY; SPACEBORNE TELESCOPES; DARK ENERGY; ECHOES
20110023332 NASA Goddard Space Flight Center, Greenbelt, MD, United States
GCN and AMON
Barthelmy, Scott; September 30, 2011; In English; Astrophysical Multimessenger Observatory Network (AMON) Workshop, 30 Sep. - 2 Oct. 2011, University Park, PA, United States
Report No.(s): GSFC.ABS.5437.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023332
"I will given an overview of the GCN system functions, capabilities, current & future notice types). Then a description of how GCN can interact with AMON; provide correlative trigger information to be used with the IceCube Neutrino detector (and others), and how GCN can distribute any detections made there from."
Author
ASTROPHYSICS; COSMOLOGY; COMMUNICATION NETWORKS; GAMMA RAY BURSTS
20110023334 NASA Goddard Space Flight Center, Greenbelt, MD, United States
GCN and SONG and Interactions with Other Instruments
Barthelmy, Scott; September 15, 2011; In English; 4th Workshop for SONG: Stellar Observations Network Group, 15-20 Sep. 2011, Charleston, SC, United States
Report No.(s): GSFC.ABS.5442.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023334
I will give a brief description of Gamma-ray burst Coordinates Network (GCN) (distribution methods, filtering criteria, etc) plus the types of notices currently being distributed (GRBs, transients, & monitoring). Then cover how Stellar Observations Network Group (SONG) telescopes could make use of these notice types to fill in some of their observing time. I will then make a pitch to get SONG telescopes to contribute those data products that are consistant with the real-time transient aspects of GCN.
Author
GAMMA RAY BURSTS; TELESCOPES; GAMMA RAY ASTRONOMY; COORDINATION
20110023335 NASA Goddard Space Flight Center, Greenbelt, MD, United States
A Global Picture of AGN Winds
Kazanas, D.; Fukumura, K.; October 14, 2011; In English; AGN Winds Conference, 15-18 Oct. 2011, Charleston, SC, United States
Report No.(s): GSFC.ABS.5444.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023335
We present a unified structure for accretion powered sources across their entire luminosity range from accreting galactic black holes to the most luminous quasars, with emphasis on AGN and their phenomenology. Central to this end is the notion of MHD winds launched from the accretion disks that power these objects. This work similar in spirit to that of Elvis of more that a decade ago, provides, on one hand, only the broadest characteristics of these objects, but on the other, also scaling laws that allow one to make contact with objects of different luminosity. The conclusion of this work is that AGN phenomenology can be accounted for in terms of dot(m), the wind mass flux in units of the Eddington value, the observer's inclination angle theta and alpha_OX the logarithmic slope between UV and X-ray flares. However given the well known correlation between alpha(sub ox) and UV Luminosity, we conclude that the AGN structure depends on only two parameters. The small number of model parameters hence suggests that an understanding of the global AGN properties maybe within reach.
Author
ACTIVE GALACTIC NUCLEI; GALACTIC RADIATION; MAGNETOHYDRODYNAMICS; GALACTIC WINDS
20110023336 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Understanding Coronal Heating with Emission Measure Distributions
Klimchik, James A.; Tripathi, Durgesh; Bradshaw, Stephen J.; Mason, Helen E.; [2011]; In English
Report No.(s): GSFC.ABS.5449.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023336
It is widely believed that the cross-field spatial scale of coronal heating is small, so that the fundamental plasma structures (loop strands) are spatially unresolved. We therefore must appeal to diagnostic techniques that are not strongly affected by spatial averaging. One valuable observable is the emission measure distribution, EM(T), which indicates how much material is present at each temperature. Using data from the Extreme-ultraviolet Imaging Spectrograph on the Hinode mission, we have determined emission measure distributions in the cores of two active regions. The distributions have power law slopes of approximately 2.4 coolward of the peak. We compare these slopes, as well as the amount of emission measure at very high temperature, with the predictions of a series of models. The models assume impulsive heating (nanoflares) in unresolved strands and take full account of non equilibrium ionization. A variety of nanoflare properties and initial conditions are considered. We also comment on the selection of spectral lines for upcoming missions like Solar Orbiter.
Author
SOLAR CORONA; HEATING; SPATIAL DISTRIBUTION; EMISSION SPECTRA
20110023337 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Solar and Heliospheric Data Requirements: Going Further Than L1
Szabo, A.; [2011]; In English
Report No.(s): GSFC.ABS.5445.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023337
Current operational space weather forecasting relies on solar wind observations made by the ACE spacecraft located at the L1 point providing 30-40 minutes warning time. Some use is also made of SOHO and STEREO solar imaging that potentially can give multiple days of warning time. However, our understanding of the propagation and evolution of solar wind transients is still limited resulting in a typical timing uncertainty of approximately 10 hours. In order to improve this critical understanding, a number of NASA missions are being planned. Specifically the Solar Probe Plus and Solar Orbiter missions will investigate the inner Heliospheric evolution of coronal mass ejections and the acceleration and propagation of solar energetic particles. In addition, a number of multi-spacecraft concepts have been studied that have the potential to significantly improve the accuracy of long-term space weather forecasts.
Author
SPACE WEATHER; SOHO MISSION; IMAGING TECHNIQUES; SOLAR PHYSICS; ADVANCED COMPOSITION EXPLORER
20110023338 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Radiolytic Impacts of Energetic Electron Irradiation on Enceladus and Mimas
Cooper, J. F.; Sittler, E. C.; Sturner, S. J.; EPSC Abstracts; 2011; vol. Volume 6; In English; EPSC-DPS Joint Meeting 2011, 2-7 OCt. 2011, Nantes, France
Report No.(s): GSFC.ABS.5450.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023338
Episodic overturn of the south polar terrain on Enceladus would convey radio lytic oxidants from surface irradiation by Saturn's inner magnetospheric electrons to the putative underlying polar sea and contribute to CO2 and other gas production driving the visibly active cryovolcanism. Low duty cycle of active episodes below 1 - 10 percent would raise the relative importance of the continuous radiolytic chemical energy input for mass and heat outflow, e.g. as compared to heating by gravitational tides. The "Pac-Man" thermal anomaly on Mimas most likely arises from leading-trailing asymmetry of electron irradiation and resultant radio lytic processing of the moon ice to a few centimeters of depth. The Mimas thermal anomaly distribution suggests a relatively stable surface unmodified by Enceladus-like geologic overturn or cryovolcanic activity. In both cases, the heavily irradiated skin depth corresponds to the sensible thermal layer probed by Cassini infrared measurements. Neutral gas and dust emissions from Enceladus limit energetic ion and plasma electron fluxes in the inner magnetosphere, thereby governing the irradiation of Mimas and other Saturn moons.
Author
ELECTRON IRRADIATION; ENCELADUS; IRRADIATION; MIMAS
20110023339 NASA Goddard Space Flight Center, Greenbelt, MD, United States
NASA Earth Science Image Analysis for Climate Change Decisions
Hilderbrand, Peter H.; October 13, 2011; In English; 2011 IEEE Applied Imagery Pattern Recognition Workshop: Imaging for Decision Making (AIPR 2011), 11-13 Oct. 2011, Washington, DC, United States
Report No.(s): GSFC.ABS.5473.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023339
This talk will briefly outline the ways in which NASA observes the Earth, then describes the NASA satellite measurements, and then proceeds to show how these measurements are used to understand the changes that are occurring as Earth's climate warms.
Author
SATELLITE OBSERVATION; CLIMATE CHANGE; IMAGE ANALYSIS; EARTH OBSERVING SYSTEM (EOS); EARTH OBSERVATIONS (FROM SPACE)
20110023340 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Messengers from the Early Solar System - Comets as Carriers of Cosmic Information
Mumma, Michael J.; October 05, 2011; In English; Isotopes in Astrochemistry Workshop: An Interstellar Heritage for Solar System Materials, 5-9 Dec. 2011, Leiden, Netherlands
Report No.(s): GSFC.ABS.5481.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023340
Viewed from a cosmic perspective, Earth is a dry planet yet its oceans are enriched in deuterium by a large factor relative to nebular hydrogen. Can comets have delivered Earth s water? The question of exogenous delivery of water and organics to Earth and other young planets is of critical importance for understanding the origin of Earth s water, and for assessing the possible existence of exo-planets similar to Earth. Strong gradients in temperature and chemistry in the proto-planetary disk, coupled with dynamical models, imply that comets from the Oort Cloud and Kuiper Disk reservoirs should have diverse composition. The primary volatiles in comets (ices native to the nucleus) provide the preferred metric, and taxonomies based on them are now beginning to emerge [1, 2, 3]. The measurement of cosmic parameters such as the nuclear spin temperatures for H2O, NH3, and CH4, and of enrichment factors for isotopologues (D/H in water and hydrogen cyanide, N-14/N-15 in CN and hydrogen cyanide) provide additional important tests for the origin of cometary material.
Author
DEUTERIUM; PROTOPLANETARY DISKS; PLANETARY EVOLUTION; EARTH (PLANET); ENRICHMENT; SOLAR SYSTEM; COMETS; HYDROGEN; METHANE
20110023341 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Effective Albedo of Vegetated Terrain at L-Band
Kurum, Mehmet; O'Neill, Peggy E.; Lang, Roger H.; [2011]; In English; 12th Specialist Meeting on Microwave Radiometry and Remote Sensing of the Environment (MICRORAD 2012), 5-9 Mar. 2012, Rome, Italy
Report No.(s): GSFC.ABS.5484.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023341
This paper derives an explicit expression for an effective albedo of vegetated terrain from the zero- and multiple- order radiative transfer (RT) model comparison. The formulation establishes a direct physical link between the effective vegetation parameterization and the theoretical description of absorption and scattering within the canopy. The paper will present an evaluation of the derived albedo for corn canopies with data taken during an experiment at Alabama A&M Winfield A. Thomas Agricultural Research Station near Huntsville, Alabama in June, 1998. The test site consisted of two 50-m x 60-m plots - one with a bare surface and the other with grass cover - and four 30-m x 50-m plots of corn at different planting densities. One corn field was planted at a full density of 9.5 plants/sq m while the others were planted at 1/3, 1/2 and 2/3 of the full density. The fields were observed with a truck-mounted L-band radiometer at incident angle of 15 degree for the period of two weeks. Soil moisture (SM) changed daily due to irrigation and natural rainfall. Variations in gravimetric SM from 18 % to 34 % were seen during this period. Ground truth data, including careful characterization of the corn size and orientation statistics, and its dielectric, was also collected and used to simulate the effective albedo for the vegetation. The single-scattering albedo is defined as the fractional power scattered from individual vegetation constituents with respect to canopy extinction. It represents single-scattering properties of vegetation elements only, and is independent of ground properties. The values of the albedo get higher when there is dense vegetation (i.e. forest, mature corn, etc.) with scatterers, such as branches and trunks (or stalks in the case of corn), which are large with respect to the wavelength. This large albedo leads to a reduction in brightness temperature in the zero-order RT solution (known as tau-omega model). Higher-order multiple-scattering RT solutions are required for proper representation of scattering within vegetation. In this paper, an expression for an effective albedo for the whole canopy including the ground is derived for use in the zero-order RT model-based SM retrieval. This effective albedo takes into account of all the processes taking place within the canopy, including multiple-scattering. This new formulation will be presented and its importance for microwave SM retrieval will be evaluated for corn canopies in conjunction with the detailed ground truth data obtained during the experiment at Alabama in 1998. Emphasis will be placed on examining how the radiometer response to SM is modified by the corn canopy scattering under different field conditions. A semi-empirical parameterization of the effective albedo will be investigated through analysis of SM and vegetation water content effects on the effective albedo.
Author
ALBEDO; CORN; MOISTURE CONTENT; VEGETATION; REFLECTANCE; PLANTS (BOTANY); RADIATIVE TRANSFER; MODELS; SOIL MOISTURE
20110023342 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Method for Identifying Probable Archaeological Sites from Remotely Sensed Data
Tilton, James C.; Comer, Douglas C.; Priebe, Carey E.; Sussman, Daniel; October 08, 2011; In English; NASA ROSES Space Archaeology Workshop on Research and World Heritage, 8-10 Oct. 2011, Baltimore, MD, United States
Contract(s)/Grant(s): 07-SAP07-0013
Report No.(s): GSFC.ABS.5485.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023342
Archaeological sites are being compromised or destroyed at a catastrophic rate in most regions of the world. The best solution to this problem is for archaeologists to find and study these sites before they are compromised or destroyed. One way to facilitate the necessary rapid, wide area surveys needed to find these archaeological sites is through the generation of maps of probable archaeological sites from remotely sensed data. We describe an approach for identifying probable locations of archaeological sites over a wide area based on detecting subtle anomalies in vegetative cover through a statistically based analysis of remotely sensed data from multiple sources. We further developed this approach under a recent NASA ROSES Space Archaeology Program project. Under this project we refined and elaborated this statistical analysis to compensate for potential slight miss-registrations between the remote sensing data sources and the archaeological site location data. We also explored data quantization approaches (required by the statistical analysis approach), and we identified a superior data quantization approached based on a unique image segmentation approach. In our presentation we will summarize our refined approach and demonstrate the effectiveness of the overall approach with test data from Santa Catalina Island off the southern California coast. Finally, we discuss our future plans for further improving our approach.
Author
REMOTE SENSING; STATISTICAL ANALYSIS; ARCHAEOLOGY; IDENTIFYING; IMAGING TECHNIQUES; RECONNAISSANCE; DETECTION
20110023343 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Models of the Solar Atmospheric Response to Flare Heating
Allred, Joel; October 17, 2011; In English; 12th RHESSI Workshop and High Energy Solar Physics Symposium, 17-21 Oct. 2011, Nanjing, China
Report No.(s): GSFC.ABS.5487.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023343
I will present models of the solar atmospheric response to flare heating. The models solve the equations of non-LTE radiation hydrodynamics with an electron beam added as a flare energy source term. Radiative transfer is solved in detail for many important optically thick hydrogen and helium transitions and numerous optically thin EUV lines making the models ideally suited to study the emission that is produced during flares. I will pay special attention to understanding key EUV lines as well the mechanism for white light production. I will also present preliminary results of how the model solar atmosphere responds to Fletcher & Hudson type flare heating. I will compare this with the results from flare simulations using the standard thick target model.
Author
ATMOSPHERIC HEATING; SOLAR ATMOSPHERE; LOCAL THERMODYNAMIC EQUILIBRIUM; HYDRODYNAMICS; EXTREME ULTRAVIOLET RADIATION; ATMOSPHERIC MODELS; ELECTRON BEAMS; HELIUM; RADIATIVE TRANSFER
20110023344 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Solar EUV Variability from FISM and SDO/EVE During Solar Minimum, Active, and Flaring Time Periods
Chamberlin, Phillip C.; [2011]; In English
Report No.(s): GSFC.ABS.5488.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023344
The Living With a Star (LWS) Focus Science Team has identified three periods of different solar activity levels for which they will be determining the Earth's Ionosphere and Thermosphere response. Not only will the team be comparing individual models (e.g. FLIP, T1MEGCM, GLOW) outcome driven by the various levels of solar activity, but the models themselves will also be compared. These models all rely on the input solar EUV (0.1 -190 nm) irradiance to drive the variability. The Flare Irradiance Spectral Model (FISM) and the EUV Variability Experiment (EVE) onboard provide the Solar Dynamics Observatory (SDO) provide the most accurate quantification of these irradiances. Presented and discussed are how much the solar EUV irradiance changes during these three scenarios, both as a function of activity and wavelength.
Author
SOLAR ACTIVITY EFFECTS; EXTREME ULTRAVIOLET RADIATION; SOLAR RADIATION; SOLAR ACTIVITY; IRRADIANCE; HELIOSEISMOLOGY; LUMINESCENCE
20110023345 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Lyman Alpha Spicule Observatory (LASO)
Chamberlin, Phillip C.; [2011]; In English
Report No.(s): GSFC.ABS.5489.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023345
The Lyman Alpha Spicule Observatory (LASO) sounding rocket will observe smallscale eruptive events called "Rapid Blue-shifted Events" (RBEs) [Rouppe van der Voort et al., 2009], the on-disk equivalent of Type-II spicules, and extend observations that explore their role in the solar coronal heating problem [De Pontieu et al., 2011]. LASO utilizes a new and novel optical design to simultaneously observe two spatial dimensions at 4.2" spatial resolution (2.1" pixels) over a 2'x2' field of view with high spectral resolution of 66mAngstroms (33mAngstroms pixels) across a broad 20Angstrom spectral window. This spectral window contains three strong chromospheric and transition region emissions and is centered on the strong Hydrogen Lyman-a emission at 1216Angstroms. This instrument makes it possible to obtain new data crucial to the physical understanding of these phenomena and their role in the overall energy and momentum balance from the upper chromosphere to lower corona. LASO was submitted March 2011 in response to the ROSES SHP-LCAS call.
Author
LYMAN ALPHA RADIATION; SPICULES; OBSERVATORIES; SOUNDING ROCKETS; SOLAR CORONA
20110023346 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Current Status of Multi-Angle Implementation of Atmospheric Correction (MAIAC) Algorithm
Lyapustin, A.; Wang, Y.; [2011]; In English
Report No.(s): GSFC.ABS.5494.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023346
A new Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm has been developed for MODIS. MAIAC uses a time series and an image based rather than pixel-based processing to perform simultaneous retrievals of aerosol properties and surface bidirectional reflectance. It is a generic algorithm which works over all land surface types with the exception of snow. MAIAC has an internal Cloud Mask, a dynamic land-water-snow classification and a surface change mask which allows it to flexibly choose processing path over different surfaces. A distinct feature of MAIAC is a high 1 km resolution of aerosol retrievals including optical thickness and fine mode fraction, which is required in different applications including the air quality analysis. An overview of the algorithm, results of AERONET validation, and examples of comparison with MODIS Collection 5 aerosol product, including Deep Blue algorithm, will be presented for different parts of the world including continental USA, Persian Gulf region and India.
Author
ATMOSPHERIC CORRECTION; ALGORITHMS; BIDIRECTIONAL REFLECTANCE; AEROSOLS; PIXELS; SPECTRAL REFLECTANCE; TIME SERIES ANALYSIS; MODIS (RADIOMETRY); IMAGING SPECTROMETERS
20110023347 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Next-Generation Aura/OMI NO2 and SO2 Products
Krotkov, Nickolay; Yang, Kai; Bucsela, Eric; Lamsal, Lok; Celarier, Edward; Swartz, William; Carn, Simon; Bhartia, Pawan; Gleason, James; Pickering, Ken; Dickerson, Russ; [2011]; In English
Report No.(s): GSFC.ABS.5495.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023347
The measurement of both SO2 and NO2 gases are recognized as an essential component of atmospheric composition missions. We describe current capabilities and limitations of the operational Aura/OMI NO2 and SO2 data that have been used by a large number of researchers. Analyses of the data and validation studies have brought to light a number of areas in which these products can be expanded and improved. Major improvements for new NASA standard (SP) NO2 product include more accurate tropospheric and stratospheric column amounts, along with much improved error estimates and diagnostics. Our approach uses a monthly NO2 climatology based on the NASA Global Modeling Initiative (GMI) chemistry-transport model and takes advantage of OMI data from cloudy scenes to find clean areas where the contribution from the trap NO2 column is relatively small. We then use a new filtering, interpolation and smoothing techniques for separating the stratospheric and tropospheric components of NO2, minimizing the influence of a priori information. The new algorithm greatly improves the structure of stratospheric features relative to the original SP. For the next-generation OMI SO2 product we plan to implement operationally the offline iterative spectral fitting (ISF) algorithm and re-process the OMI Level-2 SO2 dataset using a priori SO2 and aerosol profiles, clouds, and surface reflectivity appropriate for observation conditions. This will improve the ability to detect and quantify weak tropospheric SO2 loadings. The new algorithm is validated using aircraft in-situ data during field campaigns in China (2005 and 2008) and in Maryland (Frostburg, 2010 and DISCOVER-AQ in July 2011). The height of the SO2 plumes will also be estimated for high SO2 loading cases (e.g., volcanic eruptions). The same SO2 algorithm will be applied to the data from OMPS sensor to be launched on NPP satellite later this year. The next-generation NO2 and SO2 products will provide critical information (e.g., averaging kernels) for evaluation of chemistry-transport models, for data assimilation, and to impose top-down constraints on the SO2 and NO2 emission sources.
Author
EXHAUST EMISSION; NITROGEN DIOXIDE; SULFUR DIOXIDES; AURA SPACECRAFT; ALGORITHMS; OZONE; CLIMATOLOGY; DATA PRODUCTS
20110023348 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Coherent Evaluation of Aerosol Data Products from Multiple Satellite Sensors
Ichoku, Charles; October 03, 2011; In English; 10th AeroCom Workshop, 3-6 Oct. 2011, Kyushu, Fukuoka, Japan
Report No.(s): GSFC.ABS.5496.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023348
Aerosol retrieval from satellite has practically become routine, especially during the last decade. However, there is often disagreement between similar aerosol parameters retrieved from different sensors, thereby leaving users confused as to which sensors to trust for answering important science questions about the distribution, properties, and impacts of aerosols. As long as there is no consensus, and the inconsistencies are not well characterized and understood, there will be no way of developing reliable model inputs and climate data records from satellite aerosol measurements. Fortunately, the Aerosol Robotic Network (AERONET) is providing well-calibrated globally representative ground-based aerosol measurements corresponding to the satellite-retrieved products. Through a recently developed web-based Multi-sensor Aerosol Products Sampling System (MAPSS), we are utilizing the advantages offered by collocated AERONET and satellite products to characterize and evaluate aerosol retrieval from multiple sensors. Indeed, MAPSS and its companion statistical tool AeroStat are facilitating detailed comparative uncertainty analysis of satellite aerosol measurements from Terra-MODIS, Aqua-MODIS, Terra-MISR, Aura-OMI, Parasol-POLDER, and Calipso-CALIOP. In this presentation, we will describe the strategy of the MAPSS system, its potential advantages for the aerosol community, and the preliminary results of an integrated comparative uncertainly analysis of aerosol products from multiple satellite sensors.
Author
AEROSOLS; CLIMATE; SATELLITE OBSERVATION; AIR SAMPLING; AQUA SPACECRAFT; TERRA SPACECRAFT
20110023349 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Near-Real Time Data for Space Weather Analyses: Present Status and Future
Hesse, Michael; Pulkkinen, Antti; Zheng, Yihua; Maddox, Marlo H.; Kuznetsova, Maria M.; December 05, 2011; In English; AGU Fall Meeting 2011, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): GSFC.ABS.5497.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023349
Assessments of the present state and future evolution of the space environment heavily relies on timely access to appropriate environmental measurements. These, near real-time (nrt), measurements provide a direct assessment of local or remote space environment conditions, they contribute to a more global description of Space Weather parameters through assimilative models, and they provide essential input into forecasting models. Unlike meteorology, however, the provision of these data is not a mainstream activity in the sense that critical space environment data are often derived from research rather than operational sensors. In addition, space research is a relatively immature field, where SUbstantial gaps in our knowledge impede our ability to optimally use available data streams. In this presentation, we provide examples of presently employed nrt data streams and their utility. We further discuss challenges and opportunities associated with the present approach to space weather forecasting. Finally, an outlook toward the future will be presented.
Author
REAL TIME OPERATION; SPACE WEATHER; METEOROLOGY; AEROSPACE ENVIRONMENTS
20110023351 NASA Goddard Space Flight Center, Greenbelt, MD, United States
View-Angle Dependent AIRS Cloud Radiances: Implication for Tropical Gravity Waves and Anvil Structures
Wu, Dong L.; Gong, Jie; September 29, 2011; In English
Report No.(s): GSFC.ABS.5373.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023351
Tropical anvil clouds play important roles in redistributing energy, water in the troposphere. Interacting with dynamics at a wide range of spatial and temporal scales, they can become organized internally and form structured cells, transporting momentum vertically and laterally. To quantify small-scale structures inside cirrus and anvils, we study view-dependence of the cloud-induced radiance from Atmospheric Infrared Sounder (AIRS) using channels near CO2 absorption line. The analysis of tropical eight-year (30degS-30degN, 2003-2010) data suggests that AIRS east-views observe 10% more anvil clouds than westviews during day (13:30 LST), whereas east-views and westviews observe equally amount of clouds at midnight (1 :30 LST). For entire tropical averages, AIRS oblique views observe more anvils than the nadir views, while the opposite is true for deep convective clouds. The dominance of cloudiness in the east-view cannot be explained by AIRS sampling and cloud microphysical differences. Tilted and banded anvil structures from convective scale to mesoscale are likely the cause of the observed view-dependent cloudiness, and gravity wave-cloud interaction is a plausible explanation for the observed structures. Effects of the tilted and banded cloud features need to be further evaluated and taken into account potentially in large-scale model parameterizations because of the vertical momentum transport through cloud wave breaking.
Author
ANVIL CLOUDS; WAVE INTERACTION; GRAVITY WAVES; CIRRUS CLOUDS; CLOUD COVER; CLOUD PHYSICS
20110023352 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Updates on CCMC Activities and GSFC Space Weather Services
Zhengm Y.; Hesse, M.; Kuznetsova, M.; Pulkkinen, A.; Rastaetter, L.; Maddox, M.; Taktakishvili, A.; Berrios, D.; Chulaki, A.; Lee, H.; Macneice, P.; Mays, L.; Mendoza, A. M.; Mullinix, R.; October 13, 2011; In English
Report No.(s): GSFC.ABS.5383.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023352
In this presentation, we provide updates on CCMC modeling activities, CCMC metrics and validation studies, and other CCMC efforts. In addition, an overview of GSFC Space Weather Services (a sibling organization to the Community Coordinated Modeling Center) and its products/capabilities will be given. We show how some of the research grade models, if running in an operational mode, can help address NASA's space weather needs by providing forecasting/now casting capabilities of significant space weather events throughout the solar system.
Author
FORECASTING; SPACE WEATHER
20110023353 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Flood Inundation Mapping in the Logone Floodplain from Multi Temporal Landsat ETM+Imagery
Jung, Hahn Chul; Alsdorf, Douglas E.; Moritz, Mark; Lee, Hyongki; Vassolo, Sara; December 05, 2011; In English; 2011 American Geophysical Union (AGU) Fall Meeting, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): GSFC.ABS.5388.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023353
Yearly flooding in the Logone floodplain makes an impact on agricultural, pastoral, and fishery systems in the Lake Chad Basin. Since the flooding extent and depth are highly variable, flood inundation mapping helps us make better use of water resources and prevent flood hazards in the Logone floodplain. The flood maps are generated from 33 multi temporal Landsat Enhanced Thematic Mapper Plus (ETM+) during three years 2006 to 2008. Flooded area is classified using a short-wave infrared band whereas open water is classified by Iterative Self-organizing Data Analysis (ISODATA) clustering. The maximum flooding extent in the study area increases up to approximately 5.8K km2 in late October 2008. The study also provides strong correlation of the flooding extents with water height variations in both the floodplain and the river based on a second polynomial regression model. The water heights are from ENIVSAT altimetry in the floodplain and gauge measurements in the river. Coefficients of determination between flooding extents and water height variations are greater than 0.91 with 4 to 36 days in phase lag. Floodwater drains back to the river and to the northeast during the recession period in December and January. The study supports understanding of the Logone floodplain dynamics in detail of spatial pattern and size of the flooding extent and assists the flood monitoring and prediction systems in the catchment.
Author
CHAD; FLOOD PLAINS; FLOOD PREDICTIONS; FLOODS; LAKES; HYDROLOGY; AFRICA; SATELLITE OBSERVATION; MAPPING
20110023354 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Science Enabling Roles and Services of SPDF
McGuire, Robert E.; Bilitza, Dieter; Candey, Robert M.; Chimiak, Reine A.; Cooper, John F.; Garcia, Leonard N.; Harris, Bernard T.; Johnson, Rita C.; King, Joseph H.; Kovalick, Tamara J.; Lal, Nand; Leckner, Howard A.; Liu, Michael H.; Papitashvili, Natalia E.; Roberts, D. Aaron; July 29, 2011; In English; 2011 American Geophysical Union (AGU) Fall Meeting, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): GSFC.ABS.5377.2011; Copyright; Availability: Other Sources; Abstract Only
The current Heliophysics Science Data Management Policy defines the roles of the Space Physics Data Facility (SPDF) project as a heliophysics active Final Archive, a focus for critical data infrastructure services and a center of excellence for data and ancillary information services. This presentation will highlight some of our current activities and our understanding of why and how our services are useful to researchers, as well as SPDF's programmatic emphasis in the coming year. We will discuss how. in cooperation with the Heliophysics Virtual discipline Observatories (VxOs), we are working closely with the RBSP and MMS mission teams to support their decisions to use CDF as a primary format for their public data products, to leverage the ongoing data flows and capabilities of CDAWeb (directly and through external clients such as Autoplot) to serve their data in a multi-mission context and to use SSCWeb to assist community science planning and analysis. Among other current activities, we will also discuss and demonstrate our continuing effort to make the Virtual Space Physics Observatory (VSPO) service comprehensive in all significant and NASA relevant heliophysics data. The OMNI and OMNI High Resolution datasets remain current and heavily cited in publications. We are expanding our FTP file services to include online archived non-CDF data from all active missions, which is a re-hosting of this function from NSSDC's FTP site. We have extended the definitions of time in CDF to unambiguously and consistently handle leap seconds. We are improving SSCWeb for much faster per1ormance, more capabilities and a web services inter1ace to Query functionality. We will also review how CDAWeb data can be easily accessed within IDL and new features in CDAWeb.
Author
DATA MANAGEMENT; INFORMATION SYSTEMS; INTERNET RESOURCES; DATA SYSTEMS
Additions to the NASA Aeronautics and Space Database as of 12/20/2011
20110023355 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Auroral Current and Electrodynamics Structure Measured by Two SOunding Rockets in Flight Simultaneously
Bounds, Scott R.; Kaeppler, Steve; Kletzing, Craig; Lessard, Marc; Cohen, Ian J.; Jones, Sarah; Pfaff, Robert F.; Rowland, Douglas E.; Anderson, Brian Jay; Gjerloev, Jesper W.; Labelle, James W.; Dombrowski, Micah P.; Dudok de Wit, Thierry; Heinselman, Craig J.; December 05, 2011; In English; 2011 Fall American Geophysical Union, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): GSFC.ABS.5339.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023355
On January 29, 2009, two identically instrumented sounding rockets were launched into a sub-storm auroral arc from Poker Flat Alaska. Labeled the Auroral Currents and Electrodynamics Structure (ACES) mission, the payloads were launched to different apogees (approx.350km and approx.120km) and staggered in time so as to optimize their magnetic conjunctions. The different altitudes provided simultaneous in-situ measurements of magnetospheric input and output to the ionosphere and the ionospheric response in the lower F and E region. Measurements included 3-axis magnetic field, 2-axis electric field nominally perpendicular to the magnetic field, energetic particles, electron and ion, up to 15keV, cold plasma temperature and density. In addition, PFISR was also operating in a special designed mode to measure electric field and density profiles in the plane defined by the rocket trajectories and laterally to either side of the trajectories. Observation of the measured currents and electrodynamics structure of the auroral form encountered are presented in the context of standard auroral models and the temporal/spatial limitations of mission designs.
Author
SOUNDING ROCKETS; AURORAL ARCS; ELECTRODYNAMICS; ENERGETIC PARTICLES; IN SITU MEASUREMENT; PLASMA TEMPERATURE; AURORAS; ELECTRIC FIELDS
20110023356 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Turbulent Reconnection Rates from Cluster Observations in the Magnetosheath
Wendel, Deirdre; October 31, 2011; In English; Arcetri 2011 Workshop on Plasma Astrophysics, 17-21 Oct. 2011, Florence, Italy
Report No.(s): GSFC.ABS.5498.2011; GSFC.ABS.5393.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023356
The role of turbulence in producing fast reconnection rates is an important unresolved question. Scant in situ analyses exist. We apply multiple spacecraft techniques to a case of nonlinear turbulent reconnection in the magnetosheath to test various theoretical results for turbulent reconnection rates. To date, in situ estimates of the contribution of turbulence to reconnection rates have been calculated from an effective electric field derived through linear wave theory. However, estimates of reconnection rates based on fully nonlinear turbulence theories and simulations exist that are amenable to multiple spacecraft analyses. Here we present the linear and nonlinear theories and apply some of the nonlinear rates to Cluster observations of reconnecting, turbulent current sheets in the magnetosheath. We compare the results to the net reconnection rate found from the inflow speed. Ultimately, we intend to test and compare linear and nonlinear estimates of the turbulent contribution to reconnection rates and to measure the relative contributions of turbulence and the Hall effect.
Author
CURRENT SHEETS; MAGNETIC FIELD RECONNECTION; MAGNETOSHEATH; SIMULATION; TURBULENCE EFFECTS; SOLAR TERRESTRIAL INTERACTIONS; PLASMA TURBULENCE
20110023357 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Nonlinear Magnetosphere: Expressions in MHD and in Kinetic Models
Hesse, Michael; Birn, Joachim; December 05, 2011; In English; AGU Fall Meeting 2011, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): GSFC.ABS.5499.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023357
Like most plasma systems, the magnetosphere of the Earth is governed by nonlinear dynamic evolution equations. The impact of nonlinearities ranges from large scales, where overall dynamics features are exhibiting nonlinear behavior, to small scale, kinetic, processes, where nonlinear behavior governs, among others, energy conversion and dissipation. In this talk we present a select set of examples of such behavior, with a specific emphasis on how nonlinear effects manifest themselves in MHD and in kinetic models of magnetospheric plasma dynamics.
Author
EARTH MAGNETOSPHERE; NONLINEAR SYSTEMS; NONLINEARITY; PLASMA DYNAMICS; SPACE PLASMAS; ATMOSPHERIC MODELS; MATHEMATICAL MODELS; MAGNETOHYDRODYNAMIC WAVES
20110023358 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Radiation Design of Ion Mass Spectrometers
Sittler, Ed; Cooper, John; Christian, Eric; Moore, Tom; Sturner, Steve; Paschalidis, Nick; November 07, 2011; In English; Jupiter Icy Moons Explorer (JUICE) Instrument Workshop, 9-11 Nov. 2011, Darmstadt, Germany
Report No.(s): GSFC.ABS.5500.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023358
In the harsh radiation environment of Jupiter and with the JUpiter ICy moon Explorer (JUICE) mission including two Europa flybys where local intensities are approx. 150 krad/month behind 100 mils of Al shielding, so background from penetrating radiation can be a serious issue for detectors inside an Ion Mass Spectrometer (IMS). This can especially be important for minor ion detection designs. Detectors of choice for time-of-flight (TOF) designs are microchannel plates (MCP) and some designs may include solid state detectors (SSD). The standard approach is to use shielding designs so background event rates are low enough that the detector max rates and lifetimes are first not exceeded and then the more stringent requirement that the desired measurement can successfully be made (i.e., desired signal is sufficiently greater than background noise after background subtraction is made). GEANT codes are typically used along with various electronic techniques, but such designs need to know how the detectors will respond to the simulated primary and secondary radiations produced within the instrument. We will be presenting some preliminary measurements made on the response of MCPs to energetic electrons (20 ke V to 1400 ke V) using a Miniature TOF (MTOF) device and the High Energy Facility at Goddard Space Flight Center which has a Van de Graaff accelerator.
Author
DETECTION; MASS SPECTROMETERS; MICROCHANNEL PLATES; SOLID STATE DEVICES; IONS; EUROPA; JUPITER (PLANET)
20110023359 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Aerosol Remote Sensing from Space - Where We Stand, Where We're Heading
Kahn, Ralph; [2011]; In English
Report No.(s): GSFC.ABS.5501.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023359
The MISR and MODIS instruments aboard the NASA Earth Observing System's Terra Satellite have been collecting data containing information about the state of Earth's atmosphere and surface for over eleven years. Among the retrieved quantities are amount and type of wildfire smoke, desert dust, volcanic effluent, urban and industrial pollution particles, and other aerosols. However, the broad scientific challenges of understanding aerosol impacts on climate and health place different, and very exacting demands on our measurement capabilities. And these data sets, though much more advanced in many respects than previous aerosol data records, are imperfect. In this presentation, I will summarize current understanding of MISR and MODIS aerosol product strengths and limitations, discuss how they relate to the bigger aerosol science questions we must address, and give my view of the way forward.
Author
AEROSOLS; EARTH ATMOSPHERE; REMOTE SENSING; EARTH OBSERVATIONS (FROM SPACE); DATA PRODUCTS
20110023360 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Space Telescopes
Rigby, Jane R.; October 29, 2011; In English
Report No.(s): GSFC.ABS.5502.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023360
The science of astronomy depends on modern-day temples called telescopes. Astronomers make pilgrimages to remote mountaintops where these large, intricate, precise machines gather light that rains down from the Universe. Bit, since Earth is a bright, turbulent planet, our finest telescopes are those that have been launched into the dark stillness of space. These space telescopes, named after heroes of astronomy (Hubble, Chandra, Spitzer, Herschel), are some of the best ideas our species has ever had. They show us, over 13 billion years of cosmic history, how galaxies and quasars evolve. They study planets orbiting other stars. They've helped us determine that 95% of the Universe is of unknown composition. In short, they tell us about our place in the Universe. The next step in this journey is the James Webb Space Telescope, being built by NASA, Europe, and Canada for a 2018 launch; Webb will reveal the first galaxies that ever formed.
Author
SPACEBORNE TELESCOPES; ASTRONOMICAL OBSERVATORIES; SPACEBORNE ASTRONOMY
20110023361 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The James Webb Space Telescope: Capabilities for Exoplanet Science
Clampin, Mark; October 18, 2011; In English; Signposts of Planets, 18-20 Oct. 2011, Greenbelt, MD, United States
Report No.(s): GSFC.ABS.5503.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023361
The James Webb Space Telescope (JWST) is a large aperture (6.5 meter), cryogenic space telescope with a suite of near and mid-infrared instruments covering the wavelength range of 0.6 micron to 28 micron. JWST's primary science goal is to detect and characterize the first galaxies. It will also study the assembly of galaxies, stellar and planetary system formation, and the formation and evolution of planetary systems. We will review the design of JWST, and discuss the current status of the project, with emphasis on recent progress in the construction of the observatory. We also review the capabilities of the observatory for observations of exosolar planets and debris disks by means of coronagraphic imaging, and high contrast imaging and spectroscopy. This discussion will focus on the optical and thermal performance of the observatory, and will include the current predictions for the performance of the observatory, with special reference to the demands of exoplanet science observations.
Author
EXTRASOLAR PLANETS; IMAGING TECHNIQUES; JAMES WEBB SPACE TELESCOPE; STELLAR SYSTEMS; PLANET DETECTION; PLANETARY SYSTEMS
20110023362 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Mid-Infrared Imaging of Exo-Earths: Impact of Exozodiacal Disk Structures
Defrere, Denis; Absil, O.; Stark, C.; den Hartog, R.; Danchi, W.; October 18, 2011; In English; Signposts of Planets, 18-20 Oct. 2011, Greenbelt, MD, United States
Report No.(s): GSFC.ABS.5505.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023362
The characterization of Earth-like extrasolar planets in the mid-infrared is a significant observational challenge that could be tackled by future space-based interferometers. The presence of large amounts of exozodiacal dust around nearby main sequence stars represents however a potential hurdle to obtain mid-infrared spectra of Earth-like planets. Whereas the disk brightness only affects the integration time, the emission of resonant dust structures mixes with the planet signal at the output of the interferometer and could jeopardize the spectroscopic analysis of an Earth-like planet. Fortunately, the high angular resolution provided by space-based interferometry is sufficient to spatially distinguish most of the extended exozodiacal emission from the planetary signal and only the dust located near the planet significantly contributes to the noise level. Considering modeled resonant structures created by Earth-like planets, we address in this talk the role of exozodiacal dust in two different cases: the characterization of Super-Earth planets with single space-based Bracewell interferometers (e.g., the FKSI mission) and the characterization of Earth-like planets with 4-telescope space-based nulling interferometers (e.g., the TPF-I and Darwin projects). In each case, we derive constraints on the disk parameters that can be tolerated without jeopardizing the detection of Earth-like planets
Author
EXTRASOLAR PLANETS; COSMIC DUST; PLANET DETECTION; SPACEBORNE ASTRONOMY; ASTRONOMICAL INTERFEROMETRY; INFRARED ASTRONOMY
20110023363 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Cryo-Vacuum Testing of the Integrated Science Instrument Module for the James Webb Space Telescope
Kimble, Randy A.; Davila, P. S.; Drury, M. P.; Glazer, S. D.; Krom, J. R.; Lundquist, R. A.; Mann, S. D.; McGuffey, D. B.; Perry, R. L.; Ramey, D. D.; [2011]; In English; 219th American Astronomical Society (AAS) Meeting, 8-12 Jan. 2012, Austin, TX, United States
Report No.(s): GSFC.ABS.5506.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023363
With delivery of the science instruments for the James Webb Space Telescope (JWST) to Goddard Space Flight Center (GSFC) expected in 2012, current plans call for the first cryo-vacuum test of the Integrated Science Instrument Module (ISIM) to be carried out at GSFC in early 2013. Plans are well underway for conducting this ambitious test, which will perform critical verifications of a number of optical, thermal, and operational requirements of the IS 1M hardware, at its deep cryogenic operating temperature. We describe here the facilities, goals, methods, and timeline for this important Integration & Test milestone in the JWST program.
Author
CRYOGENIC TEMPERATURE; CRYOGENICS; JAMES WEBB SPACE TELESCOPE; VACUUM TESTS; INSTRUMENT PACKAGES; SATELLITE-BORNE INSTRUMENTS; MISSION PLANNING
20110023364 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Active Galactic Nuclei with James Webb Space Telescope (JWST)
Rigby, Jane R.; October 02, 2011; In English; Through the Infrared Looking Glass: A Dusty View of Galaxy and AGN Evolution, 2-6 Oct. 2011, Pasadena, CA, United States
Report No.(s): GSFC.ABS.5508.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023364
I'll discuss several ways in which JWST will probe the cosmic history of accretion onto supermassive black holes, and the co-evolution of host galaxies. Key investigations include: 1) Measurements of redshift, luminosity, and AGN fraction for obscured AGN candidates identified by other missions. 2) Measurements of AGN hosts at all redshifts, including stellar masses, morphology, interactions, and star formation rates. 3) Measurements of stellar mass and black hole mass in AGN at high redshift, to chart the early history of black hole and galaxy growth.
Author
ACTIVE GALACTIC NUCLEI; BLACK HOLES (ASTRONOMY); JAMES WEBB SPACE TELESCOPE
20110023365 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Time Evolution of Eta Carinae's Colliding Winds
Gull, Theodore R.; Madura, T. I.; Grobe, J. H.; Corcoran, M. F.; [2011]; In English; The Time Evolution of Eta Carinae's Colliding Winds meeting, 8-12 Jan. 2012, Austin, TX, United States
Report No.(s): GSFC.ABS.5513.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023365
We report new HST/STIS observations that map the high-ionization forbidden line emission in the inner arc second of Eta Car, the first that fully image the extended wind-wind interaction region of the massive colliding wind binary. These observations were obtained after the 2009.0 periastron at orbital phases 0.084, 0.163, and 0.323 of the 5.54-year spectroscopic cycle. We analyze the variations in brightness and morphology of the emission, and find that blue-shifted emission (-400 to -200 km/s is symmetric and elongated along the northeast-southwest axis, while the red-shifted emission (+ 100 to +200 km/s) is asymmetric and extends to the north-northwest. Comparison to synthetic images generated from a 3-D dynamical model strengthens the 3-D orbital orientation found by Madura et al. (2011), with an inclination i = 138 deg, argument of periapsis w = 270 deg, and an orbital axis that is aligned at the same P A on the sky as the symmetry axis of the Homunculus, 312 deg. We discuss the potential that these and future mappings have for constraining the stellar parameters of the companion star and the long-term variability of the system. Plain-Language Abstract: With HST, we resolved the interacting winds of the binary, Eta Carinae. With a 3-D model, we find the binary orbit axis is aligned to the Homunculus axis. This suggests a connection between the binary and Homunculus ejection mechanism.
Author
STELLAR ORBITS; BINARY STARS; ORBITAL ELEMENTS; STELLAR WINDS; COLLISIONAL PLASMAS
20110023366 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Origin and Evolution of Interstellar Dust in the Local and High-Redshift Universe
Dwek, Eliahu; October 17, 2011; In English; Cosmic Dust Grains as Diagnostics for Massive Stars Workshop, 16-18 Nov. 2011, Basel, Switzerland
Report No.(s): GSFC.ABS.5518.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023366
In this talk I will begin by reviewing our current state of knowledge regarding the origin and evolution of dust in the local solar neighborhood. Using chemical evolution models, I will discuss their many different input parameters and their uncertainties. An important consequence of these models is the delayed injection of dust from AGB stars, compared to supernova-condensed dust, into the interstellar medium. I will show that these stellar evolutionary effects on dust composition are manifested in the infrared spectra of local galaxies. The delayed production of dust in AGB stars has also important consequences for the origin of the large amount of dust detected in high-redshift galaxies, when the universe was less that - 1 Gyr old. Supernovae may have been the only viable dust sources in those galaxies. Recent observations of SN1987a show a significant mass of dust in the ejecta of this SN. Is that production rate high enough to account for the observed dust mass in these galaxies? If not, what are the alternative viable sources of dust, and how do they depend on the nature of the galaxy (starburst or AGN) and its star formation history.
Author
ASYMPTOTIC GIANT BRANCH STARS; COSMIC DUST; INTERSTELLAR MATTER; SOLAR NEIGHBORHOOD; SUPERNOVAE; ASTRONOMICAL MODELS; STELLAR EVOLUTION
20110023368 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Wave Forcing of Saturn's Equatorial Oscillation
Flasar, F. M.; Schlinder, P. J.; Guerlet, S.; Fouchet, T.; December 03, 2011; In English; American Geophysical Fall Union Meeting, 3-11 Dec. 2011, San Francisco, CA, United States
Report No.(s): GSFC.ABS.5523.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023368
Ground-based measurements and Cassini data from CIRS thermal-infrared spectra and radio-occultation soundings have characterized the spatial structure and temporal behavior of a 15-year equatorial oscillation in Saturn's stratosphere. The equatorial region displays a vertical pattern of alternating warm and cold anomalies and, concomitantly, easterly and westerly winds relative to the cloud-top winds, with a peak-to-peak amplitude of 200 m/s. Comparison of the Cassini data over a four-year period has established that the pattern of mean zonal winds and temperatures descends at a rate of roughly I scale height over 4 years. This behavior is reminiscent of the equatorial oscillations in Earth's middle atmosphere. Here the zonal-mean spatial structure and descending pattern are driven by the absorption of vertically propagating waves. The maximum excursions in the pattern of easterly and westerly winds is determined by the limits of the zonal phase velocities of the waves. Here we report on the characterization of the waves seen in the temperature profiles retrieved from the Cassini radio-occultation soundings. The equatorial profiles exhibit a complex pattern of wavelike structure with dimensions one pressure scale height and smaller. We combine a spectral decomposition with a WKBJ analysis, where the vertical wavelength is assumed to vary slowly with the ambient static stability and doppler-shifted phase velocity of the wave. Use of the temperature and zonal wind maps from CIRS makes this approach viable. On Earth, the wave forcing associated with the equatorial oscillations generates secondary meridional circulations that affect the mean flow and planetary wave ducting well away from the equator. This may relate to the triggering of the recently reported mid-latitude storms on Saturn.
Author
EQUATORIAL REGIONS; EQUATORIAL ATMOSPHERE; SATURN (PLANET); SATURN ATMOSPHERE; OSCILLATIONS; ATMOSPHERIC TEMPERATURE; PLANETARY WAVES; ATMOSPHERIC CIRCULATION
20110023369 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Program Office Technology Management Process
Benford, Dominic J.; September 22, 2011; In English; Cosmic Origins Program Analysis Group, 22-23 Sept. 2011, Baltimore, Md, United States; Original contains black and white illustrations
Report No.(s): GSFC.CPR.5398.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023369
No abstract available
PROJECT MANAGEMENT; TECHNOLOGY ASSESSMENT; TECHNOLOGICAL FORECASTING; TECHNOLOGIES; RESEARCH AND DEVELOPMENT; RESEARCH MANAGEMENT
20110023370 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Bridging Empirical and Physical Approaches for Landslide Monitoring and Early Warning
Kirschbaum, Dalia; Peters-Lidard, Christa; Adler, Robert; Kumar, Sujay; Harrison, Ken; January 2011; In English
Report No.(s): GSFC.ABS.5525.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023370
Rainfall-triggered landslides typically occur and are evaluated at local scales, using slope-stability models to calculate coincident changes in driving and resisting forces at the hillslope level in order to anticipate slope failures. Over larger areas, detailed high resolution landslide modeling is often infeasible due to difficulties in quantifying the complex interaction between rainfall infiltration and surface materials as well as the dearth of available in situ soil and rainfall estimates and accurate landslide validation data. This presentation will discuss how satellite precipitation and surface information can be applied within a landslide hazard assessment framework to improve landslide monitoring and early warning by considering two disparate approaches to landslide hazard assessment: an empirical landslide forecasting algorithm and a physical slope-stability model. The goal of this research is to advance near real-time landslide hazard assessment and early warning at larger spatial scales. This is done by employing high resolution surface and precipitation information within a probabilistic framework to provide more physically-based grounding to empirical landslide triggering thresholds. The empirical landslide forecasting tool, running in near real-time at http://trmm.nasa.gov, considers potential landslide activity at the global scale and relies on Tropical Rainfall Measuring Mission (TRMM) precipitation data and surface products to provide a near real-time picture of where landslides may be triggered. The physical approach considers how rainfall infiltration on a hillslope affects the in situ hydro-mechanical processes that may lead to slope failure. Evaluation of these empirical and physical approaches are performed within the Land Information System (LIS), a high performance land surface model processing and data assimilation system developed within the Hydrological Sciences Branch at NASA's Goddard Space Flight Center. LIS provides the capabilities to quantify uncertainty from model inputs and calculate probabilistic estimates for slope failures. Results indicate that remote sensing data can provide many of the spatiotemporal requirements for accurate landslide monitoring and early warning; however, higher resolution precipitation inputs will help to better identify small-scale precipitation forcings that contribute to significant landslide triggering. Future missions, such as the Global Precipitation Measurement (GPM) mission will provide more frequent and extensive estimates of precipitation at the global scale, which will serve as key inputs to significantly advance the accuracy of landslide hazard assessment, particularly over larger spatial scales.
Author
FORECASTING; HAZARDS; LANDSLIDES; PRECIPITATION MEASUREMENT; RAIN; REAL TIME OPERATION; REMOTE SENSING; SLOPES; STABILITY; PREDICTIONS; RISK ASSESSMENT; PERFORMANCE PREDICTION
20110023371 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Titan Haze
Anderson, Carrie M.; West, Robert; Lavvas, Panayotis; [2011]; In English
Report No.(s): GSFC.ABS.5527.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023371
The Titan haze exerts a dominating influence on surface visibility and atmospheric radiative heating at optical and near-infrared wavelengths and our desire to understand surface composition and atmospheric dynamics provides a strong motivation to study the properties of the haze. Prior to the Cassini/Huygens missions the haze was known to be global in extent, with a hemispheric contrast asymmetry, with a complicated structure in the polar vortex region poleward of about 55 deg latitude, and with a distinct layer near 370 km altitude outside of the polar vortex at the time of the Voyager 2 flyby. The haze particles measured by the Pioneer and Voyager spacecraft were both highly polarizing and strongly forward scattering, a combination that seems to require an aggregation of small (several tens of nm radius) primary particles. These same properties were seen in the Cassini orbiter and Huygens Probe data. The most extensive set of optical measurements were made inside the atmosphere by the Descent Imager/Spectral Radiometer (DISR) instrument on the Huygens Probe. At the probe location as determined by the DISR measurements the average haze particle contained about 3000 primary particles whose radius is about 40 nm. Three distinct vertical regions were seen in the DISR data with differing particle properties. Refractive indices of the particles in the main haze layer resemble those reported by Khare et al. between O.3S and about 0.7 micron but are more absorbing than the Khare et al. results between 0.7 micron and the long-wavelength limit of the DISR spectra at 1.6 micron. These and other results are described by Tomasko et al., and a broader summary of results was given by Tomasko and West,. New data continue to stream in from the Cassini spacecraft. New data analyses and new laboratory and model results continue to move the field forward. Titan's 'detached' haze layer suffered a dramatic drop in altitude near equinox in 2009 with implications for the circulation and seasonal change in the stratosphere. The book chapter associated with this talk will also present new material on thermal-infrared data analysis and on new developments in laboratory work and haze microphysical modeling.
Author
HAZE; STRATOSPHERE; THERMAL ANALYSIS; TITAN; VORTICES; TITAN ATMOSPHERE; OPTICAL PROPERTIES
20110023372 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Distinct Purine Distribution in Carbonaceous Chondrites
Callahan, Michael P.; Smith, Karen E.; Cleaves, Henderson J.; Ruzicka, Josef; Stern, Jennifer C.; Glavin, Daniel P.; House, Christopher H.; Dworkin, Jason P.; July 03, 2011; In English; Origins 2011 International Conference, 3-8 Jul. 2011, Montpellier, France
Report No.(s): GSFC.CPR.5404.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023372
Carbonaceous chondrite meteorites are known to contain a diverse suite of organic compounds, many of which are essential components of biochemistry. Amino acids, which are the monomers of proteins, have been extensively studied in such meteorites (e.g. Botta and Bada 2002; Pizzarello et aI., 2006). The origin of amino acids in meteorites has been firmly established as extraterrestrial based on their detection typically as racemic mixtures of amino acids, the presence of many non-protein amino acids, and non-terrestrial values for compound-specific deuterium, carbon, and nitrogen isotopic measurements. In contrast to amino acids, nucleobases in meteorites have been far less studied. Nucleobases are substituted one-ring (pyrimidine) or two-ring (purine) nitrogen heterocyclic compounds and serve as the information carriers of nucleic acids and in numerous coenzymes. All of the purines (adenine, guanine, hypoxanthine, and xanthine) and pyrimidines (uracil) previously reported in meteorites are biologically common and could be interpreted as the result of terrestrial contamination (e.g. van del' Velden and Schwartz, 1974.) Unlike other meteoritic organics, there have been no observations of stochastic molecular diversity of purines and pyrimidines in meteorites, which has been a criterion for establishing extraterrestrial origin. Maltins et al. (2008) performed compound-specific stable carbon isotope measurements for uracil and xanthine in the Murchison meteorite. They assigned a non-terrestrial origin for these nucleobases; however, the possibility that interfering indigenous molecules (e.g. carboxylic acids) contributed to the 13C-enriched isotope values for these nucleobases cannot be completely ruled out. Thus, the origin of these meteoritic nucleobases has never been established unequivocally. Here we report on our investigation of extracts of II different carbonaceous chondrites covering various petrographic types (Cl, CM, and CR) and degrees of aqueous alteration (l, 2, and 3) and one ureilite. Analysis via liquid chromatography coupled with electrospray triple-stage mass spectrometry or orbitrap mass spectrometry employed a targeted approach for analysis focused on the five canonical RNA/DNA nucleobases as well as 14 non-canonical pyrimidines and purines, which have bcen observed under plausible prebiotic reactions.
Author
PURINES; CARBONACEOUS CHONDRITES; AMINO ACIDS; BIOCHEMISTRY; METEORITES; ORGANIC COMPOUNDS; HETEROCYCLIC COMPOUNDS; PETROGRAPHY
20110023373 NASA Goddard Space Flight Center, Greenbelt, MD, United States
New Insights into Prebiotic Chemistry from Old Archived Miller Extracts
Parker, Eric T.; Cleaves, H. James; Dworkin, Jason P.; Glavin, Daniel P.; Callahan, Michael P.; Aubrey, Andrew D.; Lazcano, Antonio; Bada, Jeffrey L.; July 03, 2011; In English; Origins 2011 International Conference, 3-8 Jul. 2011, Montpellier, France
Report No.(s): GSFC.CPR.5405.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023373
Following the discovery of an archived set of samples from Stanley Miller's early experiments, analyses were undertaken to better understand the diversity of compounds produced from electric discharges acting on reducing gas mixtures. The paper chromatography methods that Miller used in the 1950s were only capable of detecting a few amino acids and were unable to provide substantial quantitative data relative to today's techniques. Current analytical techniques are much more sensitive and selective, and are capable of precisely quantifying a much larger range of amino acids and their enantiomeric abundances. In one study, preserved dried samples produced by Miller using a lesser-known volcanic apparatus which differed from Miller's classic apparatus in that it utilized an aspirator that injected steam into the electric discharge chamber, simulating a volcanic eruption. The volcanic apparatus produced a wider variety of amino acids than the classic configuration. Prebiotic compounds synthesized in these environments may have locally accumulated where they could have undergone further processing. An additional preserved set of samples from an experiment conducted in 1958 were also found in Miller's archived collection. These samples which had been generated using a mixture of CH4, NH3, H2S and CO2 were collected, catalogued, and stored by Miller, but for unknown reasons were never studied. In our analyses a total of 23 amino acids and 4 amines, including 7 organosulfur compounds, were detected in these samples. The major amino acids with chiral centers are racemic within the accuracy of the measurements, indicating that they are not contaminants introduced during sample storage. This experiment marks the first synthesis of sulfur amino acids from spark discharge experiments designed to imitate primordial environments. The relative yield of some amino acids, in particular the isomers of amino butyric acid, are the highest ever found in a spark discharge experiment. The simulated primordial conditions used by Miller in these experiments may serve as a model for early volcanic plume chemistry and provide insight to the possible roles such plumes may have played in abiotic organic synthesis. Additionally, the overall abundances of the synthesized amino acids in the presence of H2S are very similar to the abundances found in some carbonaceous meteorites, suggesting that H2S may have played an important role in prebiotic reactions in early solar system environments. Although experiments using a variety of gases as components of the primordial Earth's atmospheric composition and a spark discharge apparatus configured according to Miller's original or volcanic design can be readily carried out, the unique opportunity to investigate samples prepared by the pioneer in abiotic synthesis using state of the art analytical methods is of considerable historic interest.
Author
ABIOGENESIS; AMINO ACIDS; ELECTRIC SPARKS; SYNTHESIS (CHEMISTRY); CHEMICAL EVOLUTION; PROTOBIOLOGY
20110023374 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Interplanetary Magnetic Field Power Spectrum Variations in the Inner Heliosphere: A Wind and MESSENGER Study
Szabo, Adam; Koval, A.; [2011]; In English
Report No.(s): GSFC.ABS.5528.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023374
The newly reprocessed high time resolution (11/22 vectors/sec) Wind mission interplanetary magnetic field data and the similar observations made by the MESSENGER spacecraft in the inner heliosphere affords an opportunity to compare magnetic field power spectral density variations as a function of radial distance from the Sun under different solar wind conditions. In the reprocessed Wind Magnetic Field Investigation (MFI) data, the spin tone and its harmonics are greatly reduced that allows the meaningful fitting of power spectra to the approx.2 Hz limit above which digitization noise becomes apparent. The powe'r spectral density is computed and the spectral index is fitted for the MHD and ion inertial regime separately along with the break point between the two for various solar wind conditions. Wind and MESSENGER magnetic fluctuations are compared for times when the two spacecraft are close to radial and Parker field alignment. The functional dependence of the ion inertial spectral index and break point on solar wind plasma and magnetic field conditions will be discussed.
Author
INTERPLANETARY MAGNETIC FIELDS; POWER SPECTRA; WIND VELOCITY; MESSENGER (SPACECRAFT); PLASMA INTERACTIONS; SOLAR WIND; HELIOSPHERE; MAGNETOHYDRODYNAMICS
20110023375 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Ion-Neutral Coupling in Solar Prominence
Gilbert, H.; DeVore, C. R.; Karpen, J.; Kucera, T.; Antiochos, S.; Kawashima, R.; [2011]; In English
Report No.(s): GSFC.ABS.5529.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023375
Coupling between ions and neutrals in magnetized plasmas is fundamentally important to many aspects of heliophysics, including our ionosphere, the solar chromosphere, the solar wind interaction with planetary atmospheres, and the interface between the heliosphere and the interstellar medium. Ion-neutral coupling also plays a major role in the physics of solar prominences. By combining theory, modeling, and observations we are working toward a better understanding of the structure and dynamics of partially ionized prominence plasma. Two key questions are addressed in the present work: 1) what physical mechanism(s) sets the cross-field scale of prominence threads? 2) Are ion-neutral interactions responsible for the vertical flows and structure in prominences? We present initial results from a study investigating what role ion-neutral interactions play in prominence dynamics and structure. This research was supported by NASA.
Author
NEUTRAL PARTICLES; SOLAR PROMINENCES; VERTICAL DISTRIBUTION; SOLAR WIND; INTERSTELLAR MATTER; PLASMA INTERACTIONS; HELIOSPHERE; IONIC REACTIONS; PLANETARY ATMOSPHERES
20110023376 NASA Goddard Space Flight Center, Greenbelt, MD, United States
MODIS Radiometric Calibration and Uncertainty Assessment
Xiong, Xiaoxiong; Chiang, Vincent; Sun, Junqiang; Wu, Aisheng; November 15, 2011; In English; 3rd Cloud Retrieval Evaluation Workshop (CREW-3), 15-18 Nov. 2011, Madison, WI, United States
Report No.(s): GSFC.ABS.5531.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023376
Since launch, Terra and Aqua MODIS have collected more than II and 9 years of datasets for comprehensive studies of the Earth's land, ocean, and atmospheric properties. MODIS observations are made in 36 spectral bands: 20 reflective solar bands (RSB) and 16 thermal emissive bands (TEB). Compared to its heritage sensors, MODIS was developed with very stringent calibration and uncertainty requirements. As a result, MODIS was designed and built with a set of state of the art on-board calibrators (OBC), which allow key sensor performance parameters and on-orbit calibration coefficients to be monitored and updated if necessary. In terms of its calibration traceability, MODIS RSB calibration is reflectance based using an on-board solar diffuser (SD) and the TEB calibration is radiance based using an on-board blackbody (BB). In addition to on-orbit calibration coefficients derived from its OBC, calibration parameters determined from sensor pre-launch calibration and characterization are used in both the RSB and TEB calibration and retrieval algorithms. This paper provides a brief description of MODIS calibration methodologies and discusses details of its on-orbit calibration uncertainties. It assesses uncertainty contributions from individual components and differences between Terra and Aqua MODIS due to their design characteristics and on-orbit periormance. Also discussed in this paper is the use of MODIS LIB uncertainty index CUI) product.
Author
MODIS (RADIOMETRY); AQUA SPACECRAFT; TERRA SPACECRAFT; ATMOSPHERIC CHEMISTRY; CALIBRATING; DESIGN ANALYSIS; METEOROLOGICAL PARAMETERS
20110023377 NASA Goddard Space Flight Center, Greenbelt, MD, United States
From SOHO to STEREO: Understanding Propagation of Coronal Mass Ejections
Gopalswamy, Natchimuthuk; [2011]; In English
Report No.(s): GSFC.ABS.5532.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023377
Direct comparison between coronal mass ejections (CMEs) from near the Sun and their solar wind counterparts became possible roughly a decade after the discovery of CMEs (Lindsay et aL 1999). This comparison revealed that fast CMEs decelerate and slow CMEs accelerate due to the interaction with the solar wind. Gopalswamy et al (2000) quantified this interaction as an interplanetary acceleration which is useful in predicting the arrival time and speed of CMEs at 1 AU. The interplanetary acceleration is essentially due to the aerodynamic drag between the CME and the solar wind because the propelling force and the solar gravity are effective only near the Sun. Combined remote-sensing and in situ observations from SOHO and Wind/ACE have helped us estimate the influence of the solar wind on the propagation of CMEs. However, these measurements have severe limitations because the remote sensed and in-situ observations correspond to different portions of the CME. Furthermore, the true speeds of Earth-directed CMEs cannot be measured accurately from a spacecraft located along the Sun-Earth line. There have been attempts to model the CME as a cone and get the space speed of the CME, which did improve the travel time predictions. Instruments on board the Solar Terrestrial Relations Observatory (STEREO) mission were able to provide observations of Earth-arriving CMEs without projection effects, while the same CMEs were observed at Sun-Earth L1 by Wind and ACE spacecraft. The quadrature between STEREO and L1 spacecraft presented an ideal situation to study the interplanetary evolution of CMEs and test earlier model results. The quadrature observations did improve the CME travel time predictions, but additional factors such as the unusually slow solar wind, CME cannibalism, and coronal-hole deflection need to be considered to reconcile the difference between observed and predicted travel times. This point is illustrated using the 2011 February 15 CME
Author
CORONAL MASS EJECTION; REMOTE SENSING; SOLAR WIND; CORONAL HOLES; AERODYNAMIC DRAG; DEFLECTION
20110023378 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Anions in Cometary Comae
Charnley, Steven B.; [2011]; In English
Report No.(s): GSFC.ABS.5533.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023378
The presence of negative ions (anions) in cometary comae is known from Giotto mass spectrometry of IP/Halley. The anions 0-, OH-, C-, CH- and CN- have been detected, as well as unidentified anions with masses 22-65 and 85-110 amu (Chaizy et al. 1991). Organic molecular anions are known to have a significant impact on the charge balance of interstellar clouds and circumstellar envelopes and have been shown to act as catalysts for the gas-phase synthesis of larger hydrocarbon molecules in the ISM, but their importance in cometary comae has not yet been explored. We present details of the first attempt to model the chemistry of anions in cometary comae. Based on the combined chemical and hydro dynamical model of Rodgers & Charnley (2002), we investigate the role of large carbon-chain anions in cometary coma chemistry. We calculate the effects of these anions on coma thermodynamics, charge balance and examine their impact on molecule formation.
Author
ASTRONOMICAL MODELS; NEGATIVE IONS; COMETARY ATMOSPHERES; STELLAR ENVELOPES; INTERSTELLAR MATTER; MOLECULAR CLOUDS; HYDROCARBONS
20110023379 NASA Goddard Space Flight Center, Greenbelt, MD, United States
PING Gamma Ray and Neutron Measurements of a Meter-Sized Carbonaceous Asteroid Analog
Bodnarik, J.; Burger, D.; Evans, L.; Floyd, S.; Lim, L.; McClanahan, T.; Namkung, M.; Nowicki, S.; Parsons, A.; Schweitzer, J.; Starr, R.; Trombka, J.; October 23, 2011; In English; IEEE Nuclear Science Symposium, 23-28 Oct. 2011, Valencia, Spain; Original contains black and white illustrations
Report No.(s): GSFC.ABS.5534.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023379
Determining the elemental composition of carbonaceous (spectral type C) asteroids is still one of the basic problems when studying these objects. The only main source of elemental composition information for asteroids is from their optical, NIR and IR properties, which include their spectral reflectance characteristics, albedo, polarization, and the comparison of optical spectroscopy with meteorite groups corresponding to asteroids of every spectral type. Unfortunately, these sources reflect observations from widely contrasting spatial scales that presently yield a void in the continuum of microscopic and macroscopic evidence, a lack of in situ measurement confirmation, and require deeper sensing techniques to discern the nature of these asteroids. The Probing In situ with Neutrons and Gamma rays (PING) instrument is ideally suited to address this problem because it can be used to determine the bulk elemental composition, H and C content, the average atomic weight and density of the surface and subsurface layers of C-type asteroids, and can provide measurements used to determine the difference between and distinguish between different types of asteroids. We are currently developing the PING instrument that combines gamma ray and neutron detectors with a 14 Me V pulsed neutron generator to determine the in-situ bulk elemental abundances and geochemistry of C-type asteroids with a spatial resolution of 1 m down to depths of tens of cm to 1 m. One aspect of the current work includes experimentally testing and optimizing PING on a known meter-sized Columbia River basalt C-type asteroid analog sample that has a similar composition and the same neutron response as that of a C-type asteroid. An important part of this effort focuses on utilizing timing measurements to isolate gamma rays produced by neutron inelastic scattering, neutron capture and delayed activation processes. Separating the gamma ray spectra by nuclear processes results in higher precision and sensitivity elemental composition measurements. Using gated data acquisition techniques allows for the unambiguous identification of gamma ray lines from different isotopes and nuclear processes, especially in situations when limited detector resolution results in overlapping gamma ray lines that cannot be individually resolved. In this paper, we will present the PING basalt layering experimental data, taken at the test facility at NASA Goddard Space Flight Center using the time tagged event-by-event data analysis technique, compared to our MCNPX computer simulation results for the C-type asteroid and basalt layering simulant models. Comparison of these data will show the advantages, validity, and measurement sensitivity of PING's nuclear interrogation methods to obtain more precise and sensitive in situ bulk elemental composition and density measurements of the subsurface of asteroids.
Derived from text
ASTEROIDS; CHEMICAL COMPOSITION; DETECTION; GAMMA RAY SPECTRA; GEOCHEMISTRY; IN SITU MEASUREMENT; NEUTRON COUNTERS
20110023380 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Exploring the Fate of Nitrogen Heterocycles in Complex Prebiotic Mixtures
Smith, Karen E.; Callahan, Michael P.; Cleaves, Henderson J.; Dworkin, Jason P.; House, Christopher H.; July 03, 2011; In English; Origins 2011 International Conference, 3-8 Jul. 2011, Montpellier, France; Original contains black and white illustrations
Report No.(s): GSFC.CPR.5403.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023380
A long standing question in the field of prebiotic chemistry is the origin of the genetic macromolecules DNA and RNA. DNA and RNA have very complex structures with repeating subunits of nucleotides, which are composed of nucleobases (nitrogen heterocycles) connected to sugar-phosphate. Due to the instability of some nucleobases (e.g. cytosine), difficulty of synthesis and instability of D-ribose, and the likely scarcity of polyphosphates necessary for the modern nucleotides, alternative nucleotides have been proposed for constructing the first genetic material. Thus, we have begun to investigate the chemistry of nitrogen heterocycles in plausible, complex prebiotic mixtures in an effort to identify robust reactions and potential alternative nucleotides. We have taken a complex prebiotic mixture produced by a spark discharge acting on a gas mixture of N2, CO2, CH4, and H2, and reacted it with four nitrogen heterocycles: uracil, 5-hydroxymethyluracil, guanine, and isoxanthopterin (2-amino-4,7-dihydroxypteridine). The products of the reaction between the spark mixture and each nitrogen heterocycle were characterized by liquid chromatography coupled to UV spectroscopy and Orbitrap mass spectrometry. We found that the reaction between the spark mixtUl'e and isoxanthopterin formed one major product, which was a cyanide adduct. 5-hydroxymethyluracil also reacted with the spark mixture to form a cyanide adduct, uracil-5-acetonitrile, which has been synthesized previously by reacting HCN with S-hydroxymethyluracil. Unlike isoxanthopterin, the chromatogram of the 5-hydroxymethyluracil reaction was much more complex with multiple products including spark-modified dimers. Additionally, we observed that HMU readily self-polymerizes in solution to a variety of oligomers consistent with those suggested by Cleaves. Guanine and uracil, the biological nucleobases, did not react with the spark mixture, even at high temperature (100 C). This suggests that there are alternative nucleobases which are more reactive under prebiotic conditions and may have been involved in producing precursor nucleotides.
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DEOXYRIBONUCLEIC ACID; NITROGEN; NUCLEOTIDES; RIBONUCLEIC ACIDS; CHEMICAL EVOLUTION; PROTOBIOLOGY; PROTEIN SYNTHESIS; HETEROCYCLIC COMPOUNDS
20110023381 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Risk Management from GSFC Perspective
Jambulingam, Natesan; October 18, 2011; In English; Supply Chain Conference 2011, 18-20 Oct. 2011, Greenbelt, MD, United States; Original contains black and white illustrations
Report No.(s): GSFC.CPR.5416.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023381
Risk Management is an organized, systematic decision making process that efficiently identifies, analyzes, plans, tracks, controls, communicates and documents risk
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RISK; RISK MANAGEMENT; ACCIDENT PREVENTION; RISK ASSESSMENT; SAFETY MANAGEMENT; AEROSPACE SAFETY
20110023382 NASA Goddard Space Flight Center, Greenbelt, MD, United States
How Can You Support RIDM/CRM/RM Through the Use of PRA
DoVemto. Tpmu; October 19, 2011; In English; Supply Chain Conference 2011, 18-20 Oct. 2011, Greenbelt, MD, United States; Original contains black and white illustrations
Report No.(s): GSFC.CPR.5417.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023382
Probabilistic Risk Assessment (PRA) is one of key Risk Informed Decision Making (RIDM) tools. It is a scenario-based methodology aimed at identifying and assessing Safety and Technical Performance risks in complex technological systems.
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RISK; RISK ASSESSMENT; AEROSPACE SAFETY; RISK MANAGEMENT; MISSION PLANNING; PROJECT MANAGEMENT; SAFETY MANAGEMENT
20110023383 NASA Goddard Space Flight Center, Greenbelt, MD, United States
A Radiation Hard Multi-Channel Digitizer ASIC for Operation in the Harsh Jovian Environment
Aslam, Shahid; Aslam, S.; Akturk, A.; Quilligan, G.; [2011]; In English; Original contains color and black and white illustrations
Report No.(s): GSFC.BOOK.5419.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023383
In 1995, the Galileo spacecraft arrived at Jupiter to conduct follow-up experiments on pathfinder Pioneer and key Voyager discoveries especially at Io, Europa, Ganymede and Callisto. These new observations helped expand our scientific knowledge of the prominent Galilean satellites; studies revealed diversity with respect to their geology, internal structure, evolution and degree of past and present activity. Jupiter's diverse Galilean satellites, of which three are believed to harbor internal oceans, are central to understanding the habitability of icy worlds. Galileo provided for the first time compelling evidence of a near-surface global ocean on Europa. Furthermore, by understanding the Jupiter system and unraveling the history of its evolution from initial formation to the emergence of possible habitats and life, gives insight into how giant planets and their satellite systems form and evolve. Most important, new light is shed on the potential for the emergence and existence of life in icy satellite oceans. In 2009, NASA released a detailed Jupiter Europa Mission Study (EJSM) that proposed an ambitious Flagship Mission to understand more fully the satellites Europa and Ganymede within the context of the Jovian system. Key to EJSM is the NASA led Jupiter Europa Orbiter (JEO) and the ESA led Jupiter Ganymede Orbiter (JGO). JEO and JGO would execute a choreographed exploration of the Jovian system before settling into orbit around Europa and Ganymede, respectively. The National Academies Planetary Decadal Survey, 2011 has listed the NASA-led JEO as the second highest priority mission for the decade 2013-2022, and if chosen it would be launched in 2020 with arrival at Jupiter in 2025. If the JEO mission is not chosen it is anticipated that there will be opportunities in future decadal cycles. Jupiter Orbit Insertion (JOI) begins a 30-month Jovian system tour followed by nine months of science mapping after Europa Orbit Insertion (EOI) in July 2028. The orbiter will ultimately impact the surface of Europa after the mission is completed. The current JEO mission concept includes a range of instruments on the payload, to monitor dynamic phenomena (such as Io's volcanoes and Jupiters atmosphere), map the Jovian magnetosphere and its interactions with the Galilean satellites, and characterize water oceans beneath the ice shells of Europa and Ganymede. The payload includes a low mass (3.7 Kg) and low power (< 5 W) Thermal Instrument (TI) concept for measuring possible warm thermal anomalies on Europa s cold surface caused by recent (< 10,000 years) eruptive activity. Regions of anomalously high heat flow will be identified by thermal mapping using a nadir pointing, push-broom filter radiometer that provides far-IR imagery in two broad band spectral wavelength regions, 8-20 m and 20-100 m, for surface temperature measurements with better than a 2 K accuracy and a spatial resolution of 250 m/pixel obtained from a 100 Km orbit. The temperature accuracy permits a search for elevated temperatures when combined with albedo information. The spatial resolution is sufficient to resolve Europa's larger cracks and ridge axial valleys. In order to accomplish the thermal mapping, the TI uses sensitive thermopile arrays that are readout by a custom designed low-noise Multi-Channel Digitizer (MCD) ASIC that resides very close to the thermopile linear array outputs. Both the thermopile array and the MCD ASIC will need to show full functionality within the harsh Jovian radiation environment, operating at cryogenic temperatures, typically 150 K to 170 K. In the following, a radiation mitigation strategy together with a low risk Radiation-Hardened-By-Design (RHBD) methodology using commercial foundry processes is given for the design and manufacture of a MCD ASIC that will meet this challenge.
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APPLICATION SPECIFIC INTEGRATED CIRCUITS; CRYOGENIC TEMPERATURE; FAR INFRARED RADIATION; PAYLOADS; RADIOMETERS; THERMAL MAPPING; RADIATION HARDENING; GALILEAN SATELLITES; JUPITER SATELLITES; ANALOG TO DIGITAL CONVERTERS; DIGITAL ELECTRONICS
20110023384 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Design of a 3-Stage ADR for the Soft X-Ray Spectrometer Instrument on the Astro-H Mission
Shirron, Peter J.; Kimball, Mark O.; Wegel, Donald C.; Canavan, Edgar R.; DiPirro, Michael J.; June 28, 2011; In English; International Society for Optical Engineering (SPIE), 28 Jun. - 2 Jul. 2010, San Diego, CA, United States; Original contains black and white illustrations
Report No.(s): GSFC.CP.5114.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023384
The Japanese Astro-H mission will include the Soft X-ray Spectrometer (SXS) instrument, whose 36-pixel detector array of ultra-sensitive x-ray microcalorimeters requires cooling to 50 mK. This will be accomplished using a 3-stage adiabatic demagnetization refrigerator (ADR). The design is dictated by the need to operate with full redundancy with both a superfluid helium dewar at 1.3 K or below, and with a 4.5 K Joule-Thomson (JT) cooler. The ADR is configured as a 2-stage unit that is located in a well in the helium tank, and a third stage that is mounted to the top of the helium tank. The third stage is directly connected through two heat switches to the JT cooler and the helium tank, and manages heat flow between the two. When liquid helium is present, the 2-stage ADR operates in a single-shot manner using the superfluid helium as a heat sink. The third stage may be used independently to reduce the time-average heat load on the liquid to extend its lifetime. When the liquid is depleted, the 2nd and 3rd stages operate as a continuous ADR to maintain the helium tank at as low a temperature as possible - expected to be 1.2 K - and the 1st stage cools from that temperature as a single-stage, single-shot ADR. The ADR s design and operating modes are discussed, along with test results of the prototype 3-stage ADR.
Author
ADIABATIC CONDITIONS; DEMAGNETIZATION; REFRIGERATORS; CRYOGENIC EQUIPMENT; X RAY SPECTROMETERS; MAGNETIC COOLING; HELIUM
20110023386 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Workmanship Risks: Reworking Printed Circuit Board (PCB) Solder Joints
Plante, Jeannette; Paquette, Beth; October 18, 2011; In English; Supply Chain Conference 2011, 18-20 Oct. 2011, Greenbelt, MD, United States; Original contains color illustrations
Report No.(s): GSFC.CPR.5421.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023386
No abstract available
CIRCUIT BOARDS; QUALITY CONTROL; SOLDERS; SOLDERING; SOLDERED JOINTS; RISK MANAGEMENT; FAILURE
20110023387 MEI Technologies, Inc., Greenbelt, MD, United States
Single Event Effects (SEE) Testing of Embedded DSP Cores within Microsemi RTAX4000D Field Programmable Gate Array (FPGA) Devices
Perez, Christopher E.; Berg, Melanie D.; Friendlich, Mark R.; August 22, 2011; In English; Revolutionary Electronics in Space (Respace)/Military and Aerospace Programmable Logic Devices (MAPLD) 2011 Conference, 22-25 Aug. 2011, Albuquerque, NM, United States; Original contains color illustrations
Report No.(s): GSFC.CPR.5122.2011; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023387
Motivation for this work is: (1) Accurately characterize digital signal processor (DSP) core single-event effect (SEE) behavior (2) Test DSP cores across a large frequency range and across various input conditions (3) Isolate SEE analysis to DSP cores alone (4) Interpret SEE analysis in terms of single-event upsets (SEUs) and single-event transients (SETs) (5) Provide flight missions with accurate estimate of DSP core error rates and error signatures.
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FIELD-PROGRAMMABLE GATE ARRAYS; SINGLE EVENT UPSETS; DIGITAL SYSTEMS; RADIATION DAMAGE; ELECTRONIC EQUIPMENT TESTS; ELECTRONIC EQUIPMENT
20110023388 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Optical Design Trade Study for the Wide Field Infrared Survey Telescope [WFIRST]
Content, David A.; Goullioud, R.; Lehan, John P.; Mentzell, John E.; August 21, 2011; In English; SPIE Society of Photo Optical Instrumentation of Engineers, 21-25 Aug. 2011, San Diego, CA, United States; Original contains black and white illustrations
Report No.(s): GSFC.CPR.5130.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023388
The Wide Field Infrared Survey Telescope (WFIRST) mission concept was ranked first in new space astrophysics mission by the Astro2010 Decadal Survey incorporating the Joint Dark Energy Mission (JDEM)-Omega payload concept and multiple science white papers. This mission is based on a space telescope at L2 studying exoplanets [via gravitational microlensing], probing dark energy, and surveying the near infrared sky. Since the release of NWNH, the WFIRST project has been working with the WFIRST science definition team (SDT) to refine mission and payload concepts. We present the driving requirements. The current interim reference mission point design, based on the use of a 1.3m unobscured aperture three mirror anastigmat form, with focal imaging and slitless spectroscopy science channels, is consistent with the requirements, requires no technology development, and out performs the JDEM-Omega design.
Author
ASTROPHYSICS; EXTRASOLAR PLANETS; OPTICAL EQUIPMENT; SPACEBORNE TELESCOPES; INFRARED TELESCOPES; IMAGING TECHNIQUES; DESIGN ANALYSIS; GRAVITATIONAL LENSES
20110023389 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Northwest Regional Climate Assessment
Lipschultz, Fred; September 14, 2011; In English; Pacific Northwest Climate Science Conference, 13-14 Sept. 2011, Seattle, WA, United States; Original contains color illustrations
Report No.(s): GSFC.CPR.5333.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023389
Objectives are to establish a continuing, inclusive National process that: 1) synthesizes relevant science and information 2) increases understanding of what is known & not known 3) identifies information needs related to preparing for climate variability and change, and reducing climate impacts and vulnerability 4) evaluates progress of adaptation & mitigation activities 5) informs science priorities 6) builds assessment capacity in regions and sectors 7) builds understanding & skilled use of findings
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CLIMATE; CLIMATE CHANGE; ECOSYSTEMS; ENVIRONMENTS; CLIMATOLOGY; LONG TERM EFFECTS
20110023392 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Analytical Approach in DeCoM
Patel, Deepak; August 15, 2011; In English; Thermal and Fluids Analysis 2011, 15-19 Aug. 2011, Newport News, VA, United States; Original contains color illustrations
Report No.(s): GSFC.CP.5372.2011; GSFC.CPR.5380.2011; GSFC.CPR.5348.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023392
There are many papers on describing a LHP as an overall system, but few detail on the condenser section of a loop heat pipe. The DeCoM (Deepak Condenser Model) method utilizes user set initial parameters in-order to simulate a condenser by calculating the interactions between the fluid and the wall. Equations are derived for two sections of the condenser: a two-phase section and a subcooled (liquid) section. All Equations are based upon the conservation of energy theory, from which fluid temperature, and fluid quality values are solved. In order to solve for the heat transfer value, between fluid and the wall in two phase section, the Lockhart-Martinelli correlation method was implemented as a solution approach. For Liquid phase, the Reynolds number was used in-order to differentiate the flow state, from either turbulent or laminar, and Nusselt number was used to solve for the film coefficient. To represent these calculations for both sections a flow chart is presented in order to display the execution process of DeCoM. The benefit of DeCoM is that it is capable of performing preliminary analysis without requiring a license and without much of users knowledge on condensers.
Author
HEAT PIPES; WORKING FLUIDS; ENERGY CONSERVATION; CONDENSERS (LIQUEFIERS); REYNOLDS NUMBER; NUSSELT NUMBER; LIQUID PHASES
20110023393 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Update on the Fabrication and Performance of 2-D Arrays of Superconducting Magnesium Diboride (MgB2) Thermal Detectors for Outer-Planets Exploration
Lakew, Brook; Aslam, S.; [2011]; In English; Joint European Planetary Science Congress and Division of Planetary Science (DPS) annual meeting, 2-7 October 2011, Nantes, France; Original contains black and white illustrations
Report No.(s): GSFC.CPR.5354.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023393
Detectors with better performance than the current thermopile detectors that operate at room temperature will be needed at the focal plane of far-infrared instruments on future planetary exploration missions. We will present an update on recent results from the 2-D array of MgB2 thermal detectors being currently developed at NASA Goddard. Noise and sensitivity results will be presented and compared to thermal detectors currently in use on planetary missions.
Author
MAGNESIUM; BORIDES; FABRICATION; FOCAL PLANE DEVICES; SPACE EXPLORATION; THERMOPILES; SUPERCONDUCTIVITY; GAS GIANT PLANETS
20110023394 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Describing the Optical Properties of Astronomical Dust Analogs Through Numerical Techniques
Cataldo, Giuseppe; Rinehart, S.; Benford, D.; Dwek, E.; Kinzer, R.; Nuth, J.; Wollack, E.; June 30, 2011; In English; From Dust to Galaxies, 27 Jun. - 1 Jul. 2011, Paris, France; Original contains black and white illustrations
Report No.(s): GSFC.CPR.5439.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023394
No abstract available
ASTRONOMY; OPTICAL PROPERTIES; COSMIC DUST; REFRACTIVITY; MATHEMATICAL MODELS; ELECTROMAGNETIC ABSORPTION
20110023395 NASA Goddard Space Flight Center, Greenbelt, MD, United States
GRB Discoveries with Swift
Gehrels, Neil; September 26, 2011; In English; LSC-Virgo September 2011 Meeting, 26-29 Sep. 2011, Gainesville, FL`, United States; Original contains black and white illustrations
Report No.(s): GSFC.CPR.5440.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023395
No abstract available
GAMMA RAY BURSTS; GAMMA RAY ASTRONOMY; GAMMA RAY SOURCES (ASTRONOMY); AFTERGLOWS
20110023396 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Science Enabling ASICs and FEEs for the JUICE and JEO Missions
Paschalidis, Nicholas; Sittler, Ed; Cooper, John; Christian, Eric; Moore, Tom; November 07, 2011; In English; Jupiter Icy Moons Explorer (JUICE) Instrument Workshop, 7-9 Nov. 2011, Darmstadt, Germany
Report No.(s): GSFC.CPR.5452.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023396
A family of science enabling radiation hard Application Specific Integrated Circuits (ASICs), Front End Electronics (FEEs) and Event Processing Systems, with flight heritage on many NASA missions, is presented. These technologies play an important role in the miniaturization of instruments -and spacecraft systems- at the same time increasing performance and reducing power. The technologies target time of flight, position sensing, and energy measurements as well as standard housekeeping and telemetry functions for particle and fields instruments, but find applications in other instrument categories too. More specifically the technologies include: the TOF chip, 1D and 2D Delay Lines with MCP detectors, for high precision fast and low power time of flight and position sensing; the Energy chip for multichannel SSD readout with time over threshold and standard voltage read out for TDC and ADC digitization; Fast multi channel read out chip with commandable thresholds; the TRIO chip for multiplexed ADC and housekeeping etc. It should be mentioned that the ASICs include basic trigger capabilities to enable random event processing in a heavy background of penetrators and UV foreground. Typical instruments include time of flight versus energy and look angle particle analyzers such as: plasma composition, energetic particle, neutral atom imaging as well as fast plasma and deltaE/E ion/electron telescopes. Flight missions include: Cassini/LEMMS, IMAGE/HENA, MESSENGER/EPPS/MLA/X-ray/MLA, STEREO, PLUTO-NH/PEPSSI/LORI, IBEX-Lo, JUNO/JEDI, RBSP/RBSPICE, MMS/HPCA/EPD, SO/SIS. Given the proven capability on heavy radiation missions such as JUNO, MMS and RBSB, as well diverse long duration missions such as MESSENGER, PLUTO and Cassini, it is expected that these technologies will play an important role in the particle and fields (at least) instruments on the upcoming JUICE and JEO missions.
Author
APPLICATION SPECIFIC INTEGRATED CIRCUITS; MULTISPECTRAL LINEAR ARRAYS; THRESHOLD VOLTAGE; TIME MEASUREMENT; ACTUATORS; COMMAND AND CONTROL; ENERGETIC PARTICLES; DIGITAL TECHNIQUES; MULTIPLEXING; POSITION SENSING
20110023397 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Irrigation Requirement Estimation Using Vegetation Indices and Inverse Biophysical Modeling
Bounoua, Lahouari; Imhoff, Marc L.; Franks, Shannon; IGARSS 2010; July 25, 2010; pp. 1823-182; In English; International Geoscience and Remote Sensing Symposium (IGARSS 2010), 25-30 Jul. 2010, Honolulu, HI, United States; Original contains color illustrations
Report No.(s): GSFC.CPR.5457.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023397
We explore an inverse biophysical modeling process forced by satellite and climatological data to quantify irrigation requirements in semi-arid agricultural areas. We constrain the carbon and water cycles modeled under both equilibrium, balance between vegetation and climate, and non-equilibrium, water added through irrigation. We postulate that the degree to which irrigated dry lands vary from equilibrium climate conditions is related to the amount of irrigation. The amount of water required over and above precipitation is considered as an irrigation requirement. For July, results show that spray irrigation resulted in an additional amount of water of 1.3 mm per occurrence with a frequency of 24.6 hours. In contrast, the drip irrigation required only 0.6 mm every 45.6 hours or 46% of that simulated by the spray irrigation. The modeled estimates account for 87% of the total reported irrigation water use, when soil salinity is not important and 66% in saline lands.
Author
IRRIGATION; CARBON CYCLE; CLIMATOLOGY; VEGETATION; SALINITY; SOILS; AGRICULTURE
20110023398 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Production of Organic Grain Coatings by Surface-Mediated Reactions and the Consequences of This Process for Meteoritic Constituents
Nuth, Joseph A., III; Johnson, Natasha M.; November 07, 2011; In English; Workshop on Formation of the First Solids in the Solar Systems, 7-9 Nov. 2011, Kauai, HI, United States; Original contains black and white illustrations
Report No.(s): GSFC.CPR.5471.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023398
When hydrogen, nitrogen and CO are exposed to amorphous iron silicate surfaces at temperatures between 500 - 900K, a carbonaceous coating forms via Fischer-Tropsch type reactions. Under normal circumstances such a catalytic coating would impede or stop further reaction. However, we find that this coating is a better catalyst than the amorphous iron silicates that initiate these reactions. The formation of a self-perpetuating catalytic coating on grain surfaces could explain the rich deposits of macromolecular carbon found in primitive meteorites and would imply that protostellar nebulae should be rich in organic material. Many more experiments are needed to understand this chemical system and its application to protostellar nebulae.
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COATINGS; METEORITES; ORGANIC MATERIALS; SURFACE REACTIONS; CARBON MONOXIDE; RARE GASES; GRANULAR MATERIALS
20110023399 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Challenges at Petascale for Pseudo-Spectral Methods on Spheres (A Last Hurrah?)
Clune, Thomas; September 26, 2011; In English; Workshop on Advanced Computational Methods in Engineering and Environmental Science, 26-28 Sep. 2011, New York, NY, United States; Original contains black and white illustrations
Report No.(s): GSFC.CPR.5472.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023399
Conclusions: a) Proper software abstractions should enable rapid-exploration of platform-specific optimizations/ tradeoffs. b) Pseudo-spectra! methods are marginally viable for at least some classes of petascaie problems. i.e., GPU based machine with good bisection would be best. c) Scalability at exascale is possible, but the necessary resolution will make algorithm prohibitively expensive. Efficient implementations of realistic global transposes are mtricate and tedious in MPI. PS at petascaie requires exploration of a variety of strategies for spreading local and remote communic3tions. PGAS allows far simpler implementation and thus rapid exploration of variants.
Author
ALGORITHMS; OPTIMIZATION; SPECTRAL METHODS; SPHERES
20110023400 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Investigation of the Crust of the Pannonian Basin, Hungary Using Low-Altitude CHAMP Horizontal Gradient Magnetic Anomalies
Taylor, Patrick T.; Kis, Karoly I.; Puszta, Sandor; Wittmann, Geza; Kim, Hyung Rae; Toronyi, B.; December 05, 2011; In English; American Geophysical Union 2011 Fall Meeting, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): GSFC.CPR.5474.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023400
The Pannonian Basin is a deep intra-continental basin that formed as part of the Alpine orogeny. It is some 600 by 500 km in area and centered on Hungary. This area was chosen since it has one of the thinnest continental crusts in Europe and is the region of complex tectonic structures. In order to study the nature of the crustal basement we used the long-wavelength magnetic anomalies acquired by the CHAMP satellite. The SWARM constellation, scheduled to be launched next year, will have two lower altitude satellites flying abreast, with a separation of between ca. 150 to 200 km. to record the horizontal magnetic gradient. Since the CHAMP satellite has been in orbit for eight years and has obtained an extensive range of data, both vertically and horizontally there is a large enough data base to compute the horizontal magnetic gradients over the Pannonian Basin region using these many CHAMP orbits. We recomputed a satellite magnetic anomaly map, using the spherical-cap method of Haines (1985), the technique of Alsdorf et al. (1994) and from spherical harmonic coefficients of MF6 (Maus et aI., 2008) employing the latest and lowest altitude CHAMP data. We then computed the horizontal magnetic anomaly gradients (Kis and Puszta, 2006) in order to determine how these component data will improve our interpretation and to preview what the SW ARM mission will reveal with reference to the horizontal gradient anomalies. The gradient amplitude of an 1000 km northeast-southwest profile through our horizontal component anomaly map varied from 0 to 0.025 nT/km with twin positive anomalies (0.025 and 0.023 nT/km) separated by a sharp anomaly negative at o nT/km. Horizontal gradient indicate major magnetization boundaries in the crust (Dole and Jordan, 1978 and Cordell and Grauch, 1985). Our gradient anomaly was modeled with a twodimensional body and the anomaly, of some 200 km, correlates with a 200 km area of crustal thinning in the southwestern Pannonian Basin.
Author
TECTONICS; CRUSTS; GRADIENTS; MAGNETIC ANOMALIES; MAGNETIZATION; SPHERICAL CAPS
20110023401 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Effects of Forest Disturbances on Forest Structural Parameters Retrieval from Lidar Waveform Data
Ranson, K, Lon; Sun, G.; July 25, 2011; In English; International Geoscience and Remote Sensing Symposium (IGARSS 2010), 25-30 Jul. 2010, Honolulu, HI, United States; Original contains color illustrations
Report No.(s): GSFC.CPR.5478.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023401
The effect of forest disturbance on the lidar waveform and the forest biomass estimation was demonstrated by model simulation. The results show that the correlation between stand biomass and the lidar waveform indices changes when the stand spatial structure changes due to disturbances rather than the natural succession. This has to be considered in developing algorithms for regional or global mapping of biomass from lidar waveform data.
Author
FORESTS; BIOMASS; OPTICAL RADAR; WAVEFORMS; CORRELATION; STRUCTURAL DESIGN
20110023402 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Magnetospheric Multiscale (MMS) Mission Navigation Concept
Olson, Corwin; Carpenter, Russell; November 04, 2011; In English; Young Professional, Student, and Education Conference (YPSE-11), 4 Nov. 2011, MD, United States; Original contains color illustrations
Report No.(s): GSFC.CPR.5479.2011; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023402
No abstract available
MISSION PLANNING; SATELLITE CONSTELLATIONS; FORMATION FLYING; SPACE NAVIGATION; STATIONKEEPING; GLOBAL POSITIONING SYSTEM
20110023403 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Volume of Impact Melt Generated by the Formation of the South Pole-Aitken Basin
Petro, Noah E.; November 06, 2011; In English; 2011 Annual Meeting of the Lunar Exploration Analysis Group, 6-9 Nov. 2011, Houston, TX, United States; Original contains color illustrations
Report No.(s): GSFC.CPR.5491.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023403
The South Pole-Aitken Basin (SPA) is the largest, deepest, and oldest identified basin on the Moon and as such contains surfaces that are unique due to their age, composition, and depth of origin in the lunar crust [1-5] (Figure 1). SPA has been a target of intense interest as an area for robotic sample return in order to determine the age of the basin and the composition and origin of its interior [6-8]. In response to this interest there have been several efforts to estimate the likely provenance of regolith material within central SPA [9-12]. These model estimates suggest that, despite the formation of basins and craters following SPA, the regolith within SPA is dominated by locally derived material. An assumption of these models has been that the locally derived material is primarily SPA impact-melt as opposed to local basement material (e.g. unmelted lower crust). However, the definitive identification of SPA derived impact melt on the basin floor, either by remote sensing [5, 13] or via photogeology [2, 14] is extremely difficult due to the number of subsequent impacts and volcanic activity [4].
Author
LUNAR CRUST; LUNAR CRATERS; PHOTOGEOLOGY; REMOTE SENSING; STRUCTURAL BASINS; REGOLITH; IMPACT MELTS; LUNAR SURFACE
20110023405 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Test of a General Formula for Black Hole Gravitational Wave Kicks
van Meter, James R.; Miller, M. Coleman; Baker, John G.; Boggs, William D.; Kelly, Bernard J.; The Astrophysical Journal; August 20, 2010; ISSN 1538-4357; vol. Volume 719; issue No. 2; pp. 1427-143; In English
Report No.(s): GSFC.JA.5187.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023405
http://dx.doi.org/10.1088/0004-637X/719/2/1427
Although the gravitational wave kick velocity in the orbital plane of coalescing black holes has been understood for some time, apparently conflicting formulae have been proposed for the dominant outof- plane kick, each a good fit to different data sets. This is important to resolve because it is only the out-of-plane kicks that can reach more than 500 km s-l and can thus eject merged remnants from galaxies. Using a different ansatz for the out-of-plane kick, we show that we can fit almost all existing data to better than 5%. This is good enough for any astrophysical calculation and shows that the previous apparent conflict was only because the two data sets explored different aspects of the kick parameter space.
Author
GRAVITATIONAL WAVES; BLACK HOLES (ASTRONOMY); ASTROPHYSICS
20110023406 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Uncertainties Associated with Theoretically Calculated N2-Broadened Half-Widths of H2O Lines
Ma, Q.; Tipping, R. H.; Gamache, R. R.; Molecular Physics; September 2010; ISSN 0026-8976; vol. Volume 108; issue No. 17; pp. 2225-225; In English; Original contains color illustrations
Contract(s)/Grant(s): DE-AC02-05CH11231; DE-AI02-93ER61744NNG06GB23G; NNX09AB62G; FCCS-547; NNH08ZDA001N-ACLAB; NSF ATM-0803135
Report No.(s): GSFC.JA.5199.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1080/00268976.2010.505209
With different choices of the cut-offs used in theoretical calculations, we have carried out extensive numerical calculations of the N2-broadend Lorentzian half-widths of the H2O lines using the modified Robert-Bonamy formalism. Based on these results, we are able to thoroughly check for convergence. We find that, with the low-order cut-offs commonly used in the literature, one is able to obtain converged values only for lines with large half-widths. Conversely, for lines with small half-widths, much higher cut-offs are necessary to guarantee convergence. We also analyse the uncertainties associated with calculated half-widths, and these are correlated as above. In general, the smaller the half-widths, the poorer the convergence and the larger the uncertainty associated with them. For convenience, one can divide all H2O lines into three categories, large, intermediate, and small, according to their half-width values. One can use this division to judge whether the calculated half-widths are converged or not, based on the cut-offs used, and also to estimate how large their uncertainties are. We conclude that with the current Robert- Bonamy formalism, for lines in category lone can achieve the accuracy requirement set by HITRAN, whereas for lines in category 3, it 'is impossible to meet this goal.
Author
CONVERGENCE; FORMALISM; NITROGEN; WATER; LINE SPECTRA; COMPUTATION
20110023407 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Improved Hypoxia Modeling for Nutrient Control Decisions in the Gulf of Mexico
Habib, Shahid; Pickering, Ken; Tzortziou, Maria; Maninio, Antonio; Policelli, Fritz; Stehr, Jeff; [2011]; In English; Original contains black and white illustrations
Report No.(s): GSFC.JA.5218.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023407
The Gulf of Mexico Modeling Framework is a suite of coupled models linking the deposition and transport of sediment and nutrients to subsequent bio-geo chemical processes and the resulting effect on concentrations of dissolved oxygen in the coastal waters of Louisiana and Texas. Here, we examine the potential benefits of using multiple NASA remote sensing data products within this Modeling Framework for increasing the accuracy of the models and their utility for nutrient control decisions in the Gulf of Mexico. Our approach is divided into three components: evaluation and improvement of (a) the precipitation input data (b) atmospheric constituent concentrations in EPA's air quality/deposition model and (c) the calculation of algal biomass, organic carbon and suspended solids within the water quality/eutrophication models of the framework.
Author
WATER QUALITY; ATMOSPHERIC COMPOSITION; AIR QUALITY; CHEMICAL REACTIONS; COASTAL WATER; DISSOLVED GASES; REMOTE SENSING; EUTROPHICATION
20110023408 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Drake Antarctic Agile Meteor Radar (DrAAMER) First Results: Configuration and Comparison of Mean and Tidal Wind and Gravity Wave Momentum Flux Measurements with SAAMER
Fritts, D. C.; Janches, D.; Iimura, H.; Hocking, W. K.; Bageston, J. V.; Pene, N. M.; July 29, 2011; In English; Original contains color illustrations
Contract(s)/Grant(s): NSF OPP-0839084
Report No.(s): GSFC.JA.5334.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023408
A new-generation meteor radar was installed at the Brazilian Antarctic Comandante Ferraz Base (62.1degS) in March 2010. This paper describes the motivations for the radar location, its measurement capabilities, and comparisons of measured mean winds, tides, and gravity wave momentum fluxes from April to June of 2010 and 2011 with those by a similar radar on Tierra del Fuego (53.8degS). Motivations for the radars include the "hotspot" of small-scale gravity wave activity extending from the troposphere into the mesosphere and lower thermosphere (MLT) centered over the Drake Passage, the maximum of the semidiurnal tide at these latitudes, and the lack of other MLT wind measurements in this latitude band. Mean winds are seen to be strongly modulated at planetary wave and longer periods and to exhibit strong coherence over the two radars at shorter time scales as well as systematic seasonal variations. The semidiurnal tide contribute most to the large-scale winds over both radars, with maximum tidal amplitudes during May and maxima at the highest altitudes varying from approx.20 to >70 m/s. In contrast, the diurnal tide and various planetary waves achieve maximum winds of approx.10 to 20 m/s. Monthly-mean gravity wave momentum fluxes appear to reflect the occurrence of significant sources at lower altitudes, with relatively small zonal fluxes over both radars, but with significant, and opposite, meridional momentum fluxes below approx.85 km. These suggest gravity waves propagating away from the Drake Passage at both sites, and may indicate an important source region accounting in part for this "hotspot".
Author
DIURNAL VARIATIONS; AIR WATER INTERACTIONS; WATER WAVES; WIND MEASUREMENT; PLANETARY WAVES; GRAVITY WAVES; MESOSPHERE; METEOROIDS
20110023411 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Solar Wind as a Magnetofluid Turbulence Laboratory
Goldstein, Melvyn L.; October 15, 2011; In English; Arcetri 2011 Workshop on Plasma Astrophysics, 17-21 Oct. 2011, Florence, Italy
Report No.(s): GSFC.ABS.5392.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023411
The solar wind is the Sun's exosphere. As the solar atmosphere expands into interplanetary space, it is accelerated and heated. Data from spacecraft located throughout the heliosphere have revealed that this exosphere has velocities of several hundred kilometers/sec, densities at Earth orbit of about 5 particles/cu cm, and an entrained magnetic field that at Earth orbit that is about 5 10-5 Gauss. A fascinating feature of the solar wind is that the magnetic field fluctuates in a way that is highly reminiscent of "Alfven waves, i.e., the fluctuating magnetic fields are more-or-less aligned with fluctuations in the velocity of the plasma and, with proper normalization, have approximately equal magnitudes. The imperfect (observed) alignment leads to a variety of complex interactions. In many respects, the flow patterns appear to be an example of fully developed magneto fluid turbulence. Recently, the dissipation range of this turbulence has been studied using search coil magnetometer data from the STAFF instrument on the four Cluster spacecraft. I will attempt to give an overview of selected properties of this large-scale and small-scale turbulence.
Author
SOLAR WIND; MAGNETOHYDRODYNAMIC TURBULENCE; SOLAR ATMOSPHERE; EARTH ORBITS; EXOSPHERE; HELIOSPHERE; MAGNETIC FIELDS; FLOW DISTRIBUTION
20110023412 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Ocean Turbulence, III: New GISS Vertical Mixing Scheme
Canuto, V. M.; Howard, A. M.; Cheng, Y.; Muller, C. J.; Leboissetier, A.; Jayne, S. R.; Ocean Modeling; April 10, 2010; ISSN 1463-5003; vol. Volume 34; issue Iss. 3-4; pp. 70-9; In English; Original contains color illustrations
Report No.(s): GSFC.JA.5409.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023412
http://dx.doi.org/10.1016/j.ocemod.2010.04.006
We have found a new way to express the solutions of the RSM (Reynolds Stress Model) equations that allows us to present the turbulent diffusivities for heat, salt and momentum in a way that is considerably simpler and thus easier to implement than in previous work. The RSM provides the dimensionless mixing efficiencies Gamma-alpha (alpha stands for heat, salt and momentum). However, to compute the diffusivities, one needs additional information, specifically, the dissipation Epsilon. Since a dynamic equation for the latter that includes the physical processes relevant to the ocean is still not available, one must resort to different sources of information outside the RSM to obtain a complete Mixing Scheme usable in OGCMs. As for the RSM results, we show that the Gamma-alpha s are functions of both Ri and Rq (Richardson number and density ratio representing double diffusion, DD); the Gamma-alpha are different for heat, salt and momentum; in the case of heat, the traditional value Gamma-h = 0.2 is valid only in the presence of strong shear (when DD is inoperative) while when shear subsides, NATRE data show that Gamma-h can be three times as large, a result that we reproduce. The salt Gamma-s is given in terms of Gamma-h. The momentum Gamma-m has thus far been guessed with different prescriptions while the RSM provides a well defined expression for Gamma-m(Ri,R-rho). Having tested Gamma-h, we then test the momentum Gamma-m by showing that the turbulent Prandtl number Gamma-m/Gamma-h vs. Ri reproduces the available data quite well. As for the dissipation epsilon, we use different representations, one for the mixed layer (ML), one for the thermocline and one for the ocean;s bottom. For the ML, we adopt a procedure analogous to the one successfully used in PB (planetary boundary layer) studies; for the thermocline, we employ an expression for the variable epsilon/N(exp 2) from studies of the internal gravity waves spectra which includes a latitude dependence; for the ocean bottom, we adopt the enhanced bottom diffusivity expression used by previous authors but with a state of the art internal tidal energy formulation and replace the fixed Gamma-alpha = 0.2 with the RSM result that brings into the problem the Ri, R-rho dependence of the Gamma-alpha; the unresolved bottom drag, which has thus far been either ignored or modeled with heuristic relations, is modeled using a formalism we previously developed and tested in PBL studies. We carried out several tests without an OGCM. Prandtl and flux Richardson numbers vs. Ri. The RSM model reproduces both types of data satisfactorily. DD and Mixing efficiency Gamma-h(Ri,Rq). The RSM model reproduces well the NATRE data. Bimodal epsilon-distribution. NATRE data show that epsilon (Ri < 1) approximately equals 10epsilon(Ri > 1), which our model reproduces. Heat to salt flux ratio. In the Ri much greater than 1 regime, the RSM predictions reproduce the data satisfactorily. NATRE mass diffusivity. The z-profile of the mass diffusivity reproduces well the measurements at NATRE. The local form of the mixing scheme is algebraic with one cubic equation to solve.
Author
DIFFUSION; DIFFUSIVITY; HEAT FLUX; MOMENTUM; OCEAN BOTTOM; REYNOLDS STRESS; THERMOCLINES; TURBULENCE; OCEAN MODELS; OCEANOGRAPHY; MATHEMATICAL MODELS
20110023414 NASA Goddard Space Flight Center, Greenbelt, MD, United States
In Situ and Satellite Measured Temperature Comparability
Schmidlin, F. J.; Goldberg, R. A.; Bedrick, Mary; Rose, R. Lynn; December 05, 2011; In English; American Geophysical Union (AGU) Fall Meeing 2011, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): GSFC.ABS.5394.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023414
Following the International Geophysical Year in the late 1950's, small meteorological rockets caught the interest of scientists as a potentially inexpensive method to obtain meteorological information (density, temperature, wind) above balloon-borne radiosonde altitudes. These small rocketsondes have served many important observational roles in terms of studies conducted of atmospheric structure and processes, enabling many new ideas about the atmosphere to emerge. Although no longer manufactured a small residual inventory of meteorological rocketsondes exist for specific research projects. The value of data from meteorological rocketsondes is without question but with their disappearance data from many different satellites are filling the need, some able to resolve high-altitude temperatures quite well. However, the rocketsonde vertical profile is more localized to the launch site whereas satellites move several kilometers per second. The objective of this presentation is to compare in situ temperature data with remotely measured/retrieved temperature data. There have been a number of U.S. conducted missions utilizing the passive falling sphere data that we use to verify the comparability of retrieved temperatures from these satellites. Missions, some as early as 1991, were conducted in polar, equatorial, and mid-latitude locations. An important aspect is that a single satellite profile compared to a falling sphere profile often does not agree while high density satellite measurements when averaged over an area near the rocketsonde data area seems to be in better agreement. Radiosonde temperature data are used in the analysis when appropriate
Author
DENSITY MEASUREMENT; METEOROLOGICAL FLIGHT; ROCKET SOUNDING; INTERNATIONAL GEOPHYSICAL YEAR; SATELLITE OBSERVATION; RADIOSONDES; IN SITU MEASUREMENT
20110023415 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Space Weather, Geomagnetic Disturbances and Impact on the High-Voltage Transmission Systems
Pullkkinen, A.; October 09, 2011; In English; 2011 EEI Transmission, Distribution and Metering Conference, 9-13 Oct. 2011, Dallas, TX, United States
Report No.(s): GSFC.ABS.5395.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023415
Geomagnetically induced currents (GIC) affecting the performance of high-voltage power transmission systems are one of the most significant hazards space weather poses on the operability of critical US infrastructure. The severity of the threat was emphasized, for example, in two recent reports: the National Research Council (NRC) report "Severe Space Weather Events--Understanding Societal and Economic Impacts: A Workshop Report" and the North American Electric Reliability Corporation (NERC) report "HighImpact, Low-Frequency Event Risk to the North American Bulk Power System." The NRC and NERC reports demonstrated the important national security dimension of space weather and GIC and called for comprehensive actions to forecast and mitigate the hazard. In this paper we will give a brief overview of space weather storms and accompanying geomagnetic storm events that lead to GIC. We will also review the fundamental principles of how GIC can impact the power transmission systems. Space weather has been a subject of great scientific advances that have changed the wonder of the past to a quantitative field of physics with true predictive power of today. NASA's Solar Shield system aimed at forecasting of GIC in the North American high-voltage power transmission system can be considered as one of the ultimate fruits of those advances. We will review the fundamental principles of the Solar Shield system and provide our view of the way forward in the science of GIC.
Author
GEOMAGNETISM; MAGNETIC DISTURBANCES; SPACE WEATHER; ELECTRIC POWER TRANSMISSION; TRANSMISSION LINES; PREDICTIONS; MAGNETIC ANOMALIES; SOLAR ACTIVITY EFFECTS
20110023416 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Solar Drivers of 11-yr and Long-Term Cosmic Ray Modulation
Cliver, E. W.; Richardson, I. G.; Ling, A. G.; Space Science Reviews; February 24, 2011; In English; Original contains black and white illustrations
Contract(s)/Grant(s): FA8718-05-C-0036NNG06EO90A
Report No.(s): GSFC.JA.5411.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023416
http://dx.doi.org/10.1007/s11214-011-9746-3
In the current paradigm for the modulation of galactic cosmic rays (GCRs), diffusion is taken to be the dominant process during solar maxima while drift dominates at minima. Observations during the recent solar minimum challenge the pre-eminence of drift: at such times. In 2009, the approx.2 GV GCR intensity measured by the Newark neutron monitor increased by approx.5% relative to its maximum value two cycles earlier even though the average tilt angle in 2009 was slightly larger than that in 1986 (approx.20deg vs. approx.14deg), while solar wind B was significantly lower (approx.3.9 nT vs. approx.5.4 nT). A decomposition of the solar wind into high-speed streams, slow solar wind, and coronal mass ejections (CMEs; including postshock flows) reveals that the Sun transmits its message of changing magnetic field (diffusion coefficient) to the heliosphere primarily through CMEs at solar maximum and high-speed streams at solar minimum. Long-term reconstructions of solar wind B are in general agreement for the approx. 1900-present interval and can be used to reliably estimate GCR intensity over this period. For earlier epochs, however, a recent Be-10-based reconstruction covering the past approx. 10(exp 4) years shows nine abrupt and relatively short-lived drops of B to < or approx.= 0 nT, with the first of these corresponding to the Sporer minimum. Such dips are at variance with the recent suggestion that B has a minimum or floor value of approx.2.8 nT. A floor in solar wind B implies a ceiling in the GCR intensity (a permanent modulation of the local interstellar spectrum) at a given energy/rigidity. The 30-40% increase in the intensity of 2.5 GV electrons observed by Ulysses during the recent solar minimum raises an interesting paradox that will need to be resolved.
Author
CORONAL MASS EJECTION; COSMIC RAYS; TIME MEASUREMENT; SOLAR ACTIVITY EFFECTS; GALACTIC COSMIC RAYS; DIFFUSION COEFFICIENT; ATTITUDE (INCLINATION); SPECTRA; SOLAR WIND
20110023417 NASA Goddard Space Flight Center, Greenbelt, MD, United States
On the Relationship Between High Speed Solar Wind Streams and Radiation Belt Electron Fluxes
Zheng, Yihua; December 05, 2011; In English; 2011 American Geophysical (AGU) Fall Meeting, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): GSFC.ABS.5396.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023417
Both past and recent research results indicate that solar wind speed has a close connection to radiation belt electron fluxes [e.g., Paulikas and Blake, 1979; Reeves et aI., 2011]: a higher solar wind speed is often associated with a higher level of radiation electron fluxes. But the relationship can be very complex [Reeves et aI., 2011]. The study presented here provides further corroboration of this viewpoint by emphasizing the importance of a global perspective and time history. We find that all the events during years 2010 and 2011 where the >0.8 MeV integral electron flux exceeds 10(exp 5) particles/sq cm/sr/s (pfu) at GEO orbit are associated with the high speed streams (HSS) following the onset of the Stream Interaction Region (SIR), with most of them belonging to the long-lasting Corotating Interaction Region (CIR). Our preliminary results indicate that during HSS events, a maximum speed of 700 km/s and above is a sufficient but not necessary condition for the > 0.8 MeV electron flux to reach 10(exp 5) pfu. But in the exception cases of HSS events where the electron flux level exceeds the 10(exp 5) pfu value but the maximum solar wind speed is less than 700 km/s, a prior impact can be noted either from a CME or a transient SIR within 3-4 days before the arrival of the HSS - stressing the importance of time history. Through superposed epoch analysis and studies providing comparisons with the CME events and the HSS events where the flux level fails to reach the 10(exp 5) pfu, we will present the quantitative assessment of behaviors and relationships of various quantities, such as the time it takes to reach the flux threshold value from the stream interface and its dependence on different physical parameters (e.g., duration of the HSS event, its maximum or average of the solar wind speed, IMF Bz, Kp). The ultimate goal is to apply what is derived to space weather forecasting.
Author
RADIATION BELTS; ELECTRONS; FLUX (RATE); WIND VELOCITY; SPACE WEATHER; SOLAR WIND
20110023418 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Galactic Cosmic Ray Intensity Response to Interplanetary Coronal Mass Ejections/Magnetic Clouds in 1995-2009
Richardson, I. G.; Cane, H. V.; Solar Physics; May 12, 2011; vol. Volume 270; issue No. 2; pp. 609-62; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NNG06EO90A
Report No.(s): GSFC.JA.5412.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1007/s11207-011-9774-x
We summarize the response of the galactic cosmic ray (CGR) intensity to the passage of the more than 300 interplanetary coronal mass ejections (ICMEs) and their associated shocks that passed the Earth during 1995-2009, a period that encompasses the whole of Solar Cycle 23. In approx.80% of cases, the GCR intensity decreased during the passage of these structures, i.e., a "Forbush decrease" occurred, while in approx.10% there was no significant change. In the remaining cases, the GCR intensity increased. Where there was an intensity decrease, minimum intensity was observed inside the ICME in approx.90% of these events. The observations confirm the role of both post-shock regions and ICMEs in the generation of these decreases, consistent with many previous studies, but contrary to the conclusion of Reames, Kahler, and Tylka (Astrophys. 1. Lett. 700, L199, 2009) who, from examining a subset of ICMEs with flux-rope-like magnetic fields (magnetic clouds) argued that these are "open structures" that allow free access of particles including GCRs to their interior. In fact, we find that magnetic clouds are more likely to participate in the deepest GCR decreases than ICMEs that are not magnetic clouds.
Author
CORONAL MASS EJECTION; GALACTIC COSMIC RAYS; INTERPLANETARY MAGNETIC FIELDS; MAGNETIC CLOUDS; MAGNETIC FIELDS; SOLAR CYCLES
20110023419 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Solar Rotational Periodicities and the Semiannual Variation in the Solar Wind, Radiation Belt, and Aurora
Emery, Barbara A.; Richardson, Ian G.; Evans, David S.; Rich, Frederick J.; Wilson, Gordon R.; Solar Physics; May 12, 2011; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NNG03EO90A
Report No.(s): GSFC.JA.5414.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1007/s11207-011-9758-x
The behavior of a number of solar wind, radiation belt, auroral and geomagnetic parameters is examined during the recent extended solar minimum and previous solar cycles, covering the period from January 1972 to July 2010. This period includes most of the solar minimum between Cycles 23 and 24, which was more extended than recent solar minima, with historically low values of most of these parameters in 2009. Solar rotational periodicities from S to 27 days were found from daily averages over 81 days for the parameters. There were very strong 9-day periodicities in many variables in 2005 -2008, triggered by recurring corotating high-speed streams (HSS). All rotational amplitudes were relatively large in the descending and early minimum phases of the solar cycle, when HSS are the predominant solar wind structures. There were minima in the amplitudes of all solar rotational periodicities near the end of each solar minimum, as well as at the start of the reversal of the solar magnetic field polarity at solar maximum (approx.1980, approx.1990, and approx. 2001) when the occurrence frequency of HSS is relatively low. Semiannual equinoctial periodicities, which were relatively strong in the 1995-1997 solar minimum, were found to be primarily the result of the changing amplitudes of the 13.5- and 27-day periodicities, where 13.5-day amplitudes were better correlated with heliospheric daily observations and 27-day amplitudes correlated better with Earth-based daily observations. The equinoctial rotational amplitudes of the Earth-based parameters were probably enhanced by a combination of the Russell-McPherron effect and a reduction in the solar wind-magnetosphere coupling efficiency during solstices. The rotational amplitudes were cross-correlated with each other, where the 27 -day amplitudes showed some of the weakest cross-correlations. The rotational amplitudes of the > 2 MeV radiation belt electron number fluxes were progressively weaker from 27- to 5-day periods, showing that processes in the magnetosphere act as a low-pass filter between the solar wind and the radiation belt. The A(sub p)/K(sub p) magnetic currents observed at subauroral latitudes are sensitive to proton auroral precipitation, especially for 9-day and shorter periods, while the A(sub p)/K(sub p) currents are governed by electron auroral precipitation for 13.5- and 27-day periodicities.
Author
SOLAR CYCLES; AURORAS; GEOMAGNETISM; PERIODIC VARIATIONS; PROTON PRECIPITATION; RADIATION BELTS; SOLAR ACTIVITY EFFECTS; SOLAR MAGNETIC FIELD; SOLAR WIND
20110023421 NASA Goddard Space Flight Center, Greenbelt, MD, United States
How Does the Sun's Spectrum Vary?
Lean, Judith L.; DeLand, Matthew T.; September 08, 2011; In English; Original contains black and white illustrations
Report No.(s): GSFC.JA.5418.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023421
Recent observations made by the Spectral Irradiance Monitor (SIM) on the Solar Radiation and Climate Experiment (SORCE) spacecraft suggest that the Sun's visible and infrared spectral irradiance increased from 2004 to 2008, even as the total solar irradiance measured simultaneously by SORCE's Total Irradiance Monitor (TIM) decreased. As well, solar ultraviolet (UV) irradiance decreased 3 to 10 times more than expected from prior observations and model calculations of the known effects of sunspot and facular solar features. Analysis of the SIM spectral irradiance observations during the solar minimum epoch of 2008, when solar activity was essentially invariant, exposes trends in the SIM observations relative to both total solar irradiance and solar activity that are unlikely solar in origin. We suggest that the SIM's radically different solar variability characterization is a consequence of undetected instrument sensitivity drifts, not true solar spectrum changes. It is thus doubtful that simulations of climate and atmospheric change using SIM measurements are indicative of real behavior in the Earth's climate and atmosphere.
Author
SOLAR ACTIVITY EFFECTS; SUNSPOTS; SPECTRAL EMISSION; INFRARED RADIATION; LIGHT (VISIBLE RADIATION); SOLAR RADIATION
20110023422 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Solar UV Variations During the Decline of Cycle 23
DeLand, Matthew, T.; Cebula, Richard P.; [2011]; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NNH06HXl8C
Report No.(s): GSFC.JA.5420.2011; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023422
Characterization of temporal and spectral variations in solar ultraviolet irradiance over a solar cycle is essential for understanding the forcing of Earth's atmosphere and climate. Satellite measurements of solar UV variability for solar cycles 21, 22, and 23 show consistent solar cycle irradiance changes at key wavelengths (e.g. 205 nm, 250 nm) within instrumental uncertainties. All historical data sets also show the same relative spectral dependence for both short-term (rotational) and long-term (solar cycle) variations. Empirical solar irradiance models also produce long-term solar UV variations that agree well with observational data. Recent UV irradiance data from the Solar Radiation and Climate Experiment (SORCE) Spectral Irradiance Monitor (SIM) and Solar Stellar Irradiance Comparison Experiment (SOLSTICE) instruments covering the declining phase of Cycle 23 present a different picture oflong-term solar variations from previous results. Time series of SIM and SOLSTICE spectral irradiance data between 2003 and 2007 show solar variations that greatly exceed both previous measurements and predicted irradiance changes over this period, and the spectral dependence of the SIM and SOLSTICE variations during these years do not show features expected from solar physics theory. The use of SORCE irradiance variations in atmospheric models yields substantially different middle atmosphere ozone responses in both magnitude and vertical structure. However, short-term solar variability derived from SIM and SOLSTICE UV irradiance data is consistent with concurrent solar UV measurements from other instruments, as well as previous results, suggesting no change in solar physics. Our analysis of short-term solar variability is much less sensitive to residual instrument response changes than the observations of long-term variations. The SORCE long-term UV results can be explained by under-correction of instrument response changes during the first few years of measurements, rather than requiring an unexpected change in the physical behavior of the Sun.
Author
EARTH ATMOSPHERE; IRRADIANCE; SOLAR ACTIVITY; SOLAR CYCLES; SOLAR RADIATION; ULTRAVIOLET RADIATION; SOLAR TERRESTRIAL INTERACTIONS
20110023423 NASA Langley Research Center, Hampton, VA, United States
Piloted Simulation to Evaluate the Utility of a Real Time Envelope Protection System for Mitigating In-Flight Icing Hazards
Ranaudo, Richard J.; Martos, Borja; Norton, Bill W.; Gingras, David R.; Barnhart, Billy P.; Ratvasky, Thomas P.; Morelli, Eugene; October 2011; In English; Atmospheric and Space Environments Conference, 2-5 Aug. 2010, Toronto, Ontario, Canada; Original contains color illustrations
Contract(s)/Grant(s): NNX07AD58AWBS 645846,02.07.11.02
Report No.(s): NASA/TM-2011-216951; AIAA Paper 2010-7987; E-17556; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023423
The utility of the Icing Contamination Envelope Protection (ICEPro) system for mitigating a potentially hazardous icing condition was evaluated by 29 pilots using the NASA Ice Contamination Effects Flight Training Device (ICEFTD). ICEPro provides real time envelope protection cues and alerting messages on pilot displays. The pilots participating in this test were divided into two groups; a control group using baseline displays without ICEPro, and an experimental group using ICEPro driven display cueing. Each group flew identical precision approach and missed approach procedures with a simulated failure case icing condition. Pilot performance, workload, and survey questionnaires were collected for both groups of pilots. Results showed that real time assessment cues were effective in reducing the number of potentially hazardous upset events and in lessening exposure to loss of control following an incipient upset condition. Pilot workload with the added ICEPro displays was not measurably affected, but pilot opinion surveys showed that real time cueing greatly improved their situation awareness of a hazardous aircraft state.
Author
AIRCRAFT ICING; ICE FORMATION; FLIGHT TRAINING; REAL TIME OPERATION; PILOT PERFORMANCE; HAZARDS; ICE
20110023425 NASA Glenn Research Center, Cleveland, OH, United States
Advanced Stirling Convertor (ASC-E2) Performance Testing at NASA Glenn Research Center
Oriti, Salvatore; Wilson, Scott; November 2011; In English; Nuclear and Emerging Technologies for Space (NETS-2011), 7-10 Feb. 2011, Albuquerque, NM, United States; Original contains color illustrations
Contract(s)/Grant(s): WBS 138494.05.02.04.02
Report No.(s): NASA/TM-2011-217102; NETS-2011-3496; E-17610-1; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023425
The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) has been supporting development of the Advanced Stirling Radioisotope Generator (ASRG) since 2006. A key element of the ASRG Project is providing life, reliability, and performance testing of the Advanced Stirling Convertor (ASC). For this purpose, four pairs of ASCs capable of operating to 850 C and designated with the model number ASC-E2, were delivered by Sunpower of Athens, Ohio, to GRC in 2010. The ASC-E2s underwent a series of tests that included workmanship vibration testing, performance mapping, and extended operation. Workmanship vibration testing was performed following fabrication of each convertor to verify proper hardware build. Performance mapping consisted of operating each convertor at various conditions representing the range expected during a mission. Included were conditions representing beginning-of-mission (BOM), end-of-mission (EOM), and fueling. This same series of tests was performed by Sunpower prior to ASC-E2 delivery. The data generated during the GRC test were compared to performance before delivery. Extended operation consisted of a 500-hr period of operation with conditions maintained at the BOM point. This was performed to demonstrate steady convertor performance following performance mapping. Following this initial 500-hr period, the ASC-E2s will continue extended operation, controller development and special durability testing, during which the goal is to accumulate tens of thousands of hours of operation. Data collected during extended operation will support reliability analysis. Performance data from these tests is summarized in this paper.
Author
STIRLING CYCLE; RELIABILITY ANALYSIS; PERFORMANCE TESTS; DURABILITY
20110023426 NASA Glenn Research Center, Cleveland, OH, United States
Natural Convection Cooling of the Advanced Stirling Radioisotope Generator Engineering Unit
Lewandowski, Edward J.; Hill, Dennis; November 2011; In English; Nuclear and Emerging Technologies for Space (NETS-2011), 7-10 Feb. 2011, Albuquerque, NM, United States; Original contains color illustrations
Contract(s)/Grant(s): WBS 138494.05.02.04.02
Report No.(s): NASA/TM-2011-217101; NETS-2011-3609; E-17609; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023426
After fueling and prior to launch, the Advanced Stirling Radioisotope Generator (ASRG) will be stored for a period of time then moved to the launch pad for integration with the space probe and mounting on the launch vehicle. During this time, which could be as long as 3 years, the ASRG will operate continuously with heat rejected from the housing and fins. Typically, the generator will be cooled by forced convection using fans. During some of the ground operations, maintaining forced convection may add significant complexity, so allowing natural convection may simplify operations. A test was conducted on the ASRG Engineering Unit (EU) to quantify temperatures and operating parameters with natural convection only and determine if the EU could be safely operated in such an environment. The results show that with natural convection cooling the ASRG EU Stirling convertor pressure vessel temperatures and other parameters had significant margins while the EU was operated for several days in this configuration. Additionally, an update is provided on ASRG EU testing at NASA Glenn Research Center, where the ASRG EU has operated for over 16,000 hr and underwent extensive testing.
Author
STIRLING CYCLE; GROUND OPERATIONAL SUPPORT SYSTEM; PRESSURE VESSELS; FREE CONVECTION; FORCED CONVECTION; FINS; LAUNCH VEHICLES
20110023427 NASA Glenn Research Center, Cleveland, OH, United States
Impact of Material and Architecture Model Parameters on the Failure of Woven Ceramic Matrix Composites (CMCs) Via the Multiscale Generalized Method of Cells
Liu, Kuang C.; Arnold, Steven M.; November 2011; In English; 35th International Conference and Exposition on Advanced Ceramics and Composites (ICACC 2011), 23-28 Jan. 2011, Daytona Beach, FL, United States; Original contains color illustrations
Contract(s)/Grant(s): WBS 031102.02.02.03.0249.11
Report No.(s): NASA/TM-2011-217011; E-17674; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023427
It is well known that failure of a material is a locally driven event. In the case of ceramic matrix composites (CMCs), significant variations in the microstructure of the composite exist and their significance on both deformation and life response need to be assessed. Examples of these variations include changes in the fiber tow shape, tow shifting/nesting and voids within and between tows. In the present work, the effects of many of these architectural parameters and material scatter of woven ceramic composite properties at the macroscale (woven RUC) will be studied to assess their sensitivity. The recently developed Multiscale Generalized Method of Cells methodology is used to determine the overall deformation response, proportional elastic limit (first matrix cracking), and failure under tensile loading conditions. The macroscale responses investigated illustrate the effect of architectural and material parameters on a single RUC representing a five harness satin weave fabric. Results shows that the most critical architectural parameter is weave void shape and content with other parameters being less in severity. Variation of the matrix material properties was also studied to illustrate the influence of the material variability on the overall features of the composite stress-strain response.
Author
CERAMIC MATRIX COMPOSITES; MICROSTRUCTURE; MATRIX MATERIALS; STRESS-STRAIN RELATIONSHIPS
20110023428 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Einstein, the Universe, and All That: An Introduction to Relativity
Prescod-Weinstein, Chandra; September 21, 2011; In English; 2011 Joint Annual Conference of the National Society of Black Physicists (NSBP) and the National Society of Hispanic Physicits (NSHP), 21-24 Sep. 2011, Austin, TX, United States
Report No.(s): GSFC.ABS.5400.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023428
Black holes) an expanding universe) space and time inextricably tied together) GPS ... What was this Einstein guy thinking?!? In this tutorial) I'll give an overview of Einstein's theories of relativity and the wild things they say about our Universe. What really happens when a particle crosses an event horizon? What is the future of the Universe? And how can we know it? Wh I'll try to touch on these questions and in so doing) give the talks in the Cosmology) Gravitation and Relativity sessions some context.
Author
BLACK HOLES (ASTRONOMY); COSMOLOGY; UNIVERSE; RELATIVITY; GRAVITATION
20110023429 NASA Glenn Research Center, Cleveland, OH, United States
Peak Satellite-to-Earth Data Rates Derived From Measurements of a 20 Gbps Bread-Board Modem
Landon, David G.; Simons, Rainee N.; Wintucky, Edwin G.; Sun, Jun Y.; Winn, James S.; Laraway, Stephen A.; McIntire, William K.; Metz, John L.; Smith, Francis J.; November 2011; In English; MILCOM 2011, 7-10 Nov. 2011, Baltimore, MD, United States; Original contains color illustrations
Contract(s)/Grant(s): WBS 432938.11.01.03.02.02.15
Report No.(s): NASA/TM-2011-217241; E-17997; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023429
A prototype data link using a Ka-band space qualified, high efficiency 200 W TWT amplifier and a bread-board modem emulator were created to explore the feasibility of very high speed communications in satellite-to-earth applications. Experiments were conducted using a DVB-S2-like waveform with modifications to support up to 20 Gbps through the addition of 128-Quadrature Amplitude Modulation (QAM). Limited by the bandwidth of the amplifier, a constant peak symbol rate of 3.2 Giga-symbols/sec was selected and the modulation order was varied to explore what peak data rate might be supported by an RF link through this amplifier. Using 128-QAM, an implementation loss of 3 dB was observed at 20 Gbps, and the loss decreased as data rate or bandwidth were reduced. Building on this measured data, realistic link budget calculations were completed. Low-Earth orbit (LEO) missions based on this TWTA with reasonable hardware assumptions and antenna sizing are found to be bandwidth-limited, rather than power-limited, making the spectral efficiency of 9/10-rate encoded 128-QAM very attractive. Assuming a bandwidth allocation of 1 GHz, these computations indicate that low-Earth orbit vehicles could achieve data rates up to 5 Gbps-an order of magnitude beyond the current state-of-practice, yet still within the processing power of a current FPGA-based software-defined modem. The measured performance results and a description of the experimental setup are presented to support these conclusions.
Author
TRAVELING WAVE AMPLIFIERS; COMMUNICATION SATELLITES; EXTREMELY HIGH FREQUENCIES; FIELD-PROGRAMMABLE GATE ARRAYS; QUADRATURE AMPLITUDE MODULATION; RATES (PER TIME); RADIO FREQUENCIES
20110023430 NASA Goddard Space Flight Center, Greenbelt, MD, United States
X-Ray Binary Populations in a Cosmological Context, Including NuSTAR Predictions
Cardiff, Ann Hornschemeier; November 08, 2011; In English; High Energy Views of Galaxies and Their Nuclei: A Symposium to Celebrate the 60th Birthday of Martin Elvis and Giuseppina Fabbiano, 8-11 Nov. 2011, Tulum, Mexico
Report No.(s): GSFC.ABS.5410.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023430
The new ultradeep 4 Ms Chandra Deep Field South has afforded the deepest view ever of X-ray binary populations. We report on the latest results on both LMXB and HMXB evolution out to redshifts of approximately four, including comparison with the latest theoretical models, using this deepest-ever view of the X-ray universe with Chandra. The upcoming NuSTAR mission will open up X-ray binary populations in the hard X-ray band, similar to the pioneering work of Fabbiano et al. in the Einstein era. We report on plans to study both Local Group and starburst galaxies as well as the implications those observations may have for X-ray binary populations in galaxies contributing to the Cosmic X-ray Background.
Author
X RAY BINARIES; STARBURST GALAXIES; COSMOLOGY; BACKGROUND RADIATION; RED SHIFT
20110023431 NASA Glenn Research Center, Cleveland, OH, United States
Advanced Technology Subsonic Transport Study: N+3 Technologies and Design Concepts
Raymer, Daniel P.; Wilson, Jack; Perkins, H. Douglas; Rizzi, Arthur; Zhang, Mengmeng; RamirezPuentes, Alfredo; November 2011; In English; Original contains color illustrations
Contract(s)/Grant(s): NNC08VF71PWBS 561581.02.08.03.13.05
Report No.(s): NASA/TM-2011-217130; E-17819; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023431
Conceptual Research Corporation, the Science of the Possible, has completed a two-year study of concepts and technologies for future airliners in the 180-passenger class. This NASA-funded contract was primarily focused on the ambitious goal of a 70 percent reduction in fuel consumption versus the market-dominating Boeing 737-800. The study is related to the N+3 contracts awarded in 2008 by NASA s Aeronautics Research Mission Directorate to teams led by Boeing, GE Aviation, MIT, and Northrop Grumman, but with more modest goals and funding. CRC s contract featured a predominant emphasis on propulsion and fuel consumption, but since fuel consumption depends upon air vehicle design as much as on propulsion technology, the study included notional vehicle design, analysis, and parametric studies. Other NASA goals including NOx and noise reduction are of long-standing interest but were not highlighted in this study, other than their inclusion in the propulsion system provided to CRC by NASA. The B-737-800 was used as a benchmark, parametric tool, and design point of departure. It was modeled in the RDS-Professional aircraft design software then subjected to extensive parametric variations of parasitic drag, drag-due-to-lift, specific fuel consumption, and unsized empty weight. These studies indicated that the goal of a 70 percent reduction in fuel consumption could be attained with roughly a 30 percent improvement in all four parameters. The results were then fit to a Response Surface and coded for ease of use in subsequent trade studies. Potential technologies to obtain such savings were identified and discussed. More than 16 advanced concept designs were then prepared, attempting to investigate almost every possible emerging concept for application to this class airliner. A preliminary assessment of these concepts was done based on their total wetted area after design normalization of trimmed maximum lift. This assessment points towards a Tailless Airliner concept which was designed and analyzed in some detail. To make it work, a retracting canard and an all-moving chin rudder were employed, along with the use of the Active Aeroelastic Wing technology. Results indicate that a 60 percent savings in fuel burn may be credibly attained, but this depends upon a lot of technology maturation, concept development, and risk reduction. This should be expected-such a dramatic reduction in fuel consumption is a "game changer" in the world of commercial aviation. It won t be easy.
Author
BOEING 737 AIRCRAFT; TRANSPORT AIRCRAFT; CANARD CONFIGURATIONS; COMMERCIAL AIRCRAFT; DESIGN ANALYSIS; FUEL CONSUMPTION; NOISE REDUCTION; SUBSONIC SPEED; AEROELASTICITY
20110023432 QinetiQ North America, Cleveland, OH, United States
Software Users Manual (SUM): Extended Testability Analysis (ETA) Tool
Maul, William A.; Fulton, Christopher E.; November 2011; In English; Original contains color illustrations
Contract(s)/Grant(s): NNC06BA07B
Report No.(s): NASA/CR-2011-217240; E-17996; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023432
This software user manual describes the implementation and use the Extended Testability Analysis (ETA) Tool. The ETA Tool is a software program that augments the analysis and reporting capabilities of a commercial-off-the-shelf (COTS) testability analysis software package called the Testability Engineering And Maintenance System (TEAMS) Designer. An initial diagnostic assessment is performed by the TEAMS Designer software using a qualitative, directed-graph model of the system being analyzed. The ETA Tool utilizes system design information captured within the diagnostic model and testability analysis output from the TEAMS Designer software to create a series of six reports for various system engineering needs. The ETA Tool allows the user to perform additional studies on the testability analysis results by determining the detection sensitivity to the loss of certain sensors or tests. The ETA Tool was developed to support design and development of the NASA Ares I Crew Launch Vehicle. The diagnostic analysis provided by the ETA Tool was proven to be valuable system engineering output that provided consistency in the verification of system engineering requirements. This software user manual provides a description of each output report generated by the ETA Tool. The manual also describes the example diagnostic model and supporting documentation - also provided with the ETA Tool software release package - that were used to generate the reports presented in the manual
Author
SYSTEMS ENGINEERING; USER MANUALS (COMPUTER PROGRAMS); APPLICATIONS PROGRAMS (COMPUTERS); COMMERCIAL OFF-THE-SHELF PRODUCTS; GRAPH THEORY
20110023433 NASA Goddard Space Flight Center, Greenbelt, MD, United States
AIRES and RAPEAS on the Move
Janches, Diego; Brunini, Claudio; November 07, 2011; In English; Second Low0Latitude Ionospheric Sensor Network (LISN) Workshop, 7-10 Nov. 2011, Sao Jose dos Campos, Brazil
Report No.(s): GSFC.ABS.5406.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023433
We report on this presentation an update on two closely related projects with relevance to LISN: AIRES (Argentina Ionospheric Radar Experiment Station) and RAPEAS (Spanish acronym for Argentina Network for Upper Atmosphere Research). AIRES' main goal is the deployment and long term operation of a face of the Afvance Modular Incoherent Scatter Radar (AMISR) close to La Plata city, in Argentina, where it is possible to perform ionospheric measurements of the geomagnetic conjugate point of the Arecibo Observatory in Puerto Rico. The initial construction of 16 AMISR panels and the infrastructure for the their deployment in Argentina have been initiated in March 2011, in the framework of a memorandum of understanding agreed between the U.S. National Science Foundation (NSF) and the Argentina National Council for Scientific and Technical Research (CONICET). In addition, in August 2011, CONICET created RAPEAS, which main objective is to maximize the benefits of AIRES as well as other networks and instruments in Argentina dedicated to Upper Atmosphere research. Over forty scientist and engineers from fifteen scientific and academic institutions are currently part of RAPE AS. Both, RAPEAS and AIRES will create a great synergy within the Argentina Upper Atmosphere community and will open new opportunities for international collaborations among which, the LISN project should play a relevant role.
Author
ARGENTINA; CONSTRUCTION; GEOMAGNETISM; UPPER ATMOSPHERE
20110023434 NASA Glenn Research Center, Cleveland, OH, United States
Lateral Load Testing of the Advanced Stirling Convertor (ASC-E2) Heater Head
Cornell, Peggy A.; Krause, David L.; Davis, Glen; Robbie, Malcolm G.; Gubics, David A.; November 2011; In English; 8th International Energy Conversion Engineering Conference (IECEC), 28-5-28 Jul. 2010, Nashville, TN, United States; Original contains color illustrations
Contract(s)/Grant(s): WBS 138494.05.02.04.01
Report No.(s): NASA/TM-2011-217103; AIAA Paper 2010-6692; E-17727-1; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023434
Free-piston Stirling convertors are fundamental to the development of NASA s next generation of radioisotope power system, the Advanced Stirling Radioisotope Generator (ASRG). The ASRG will use General Purpose Heat Source (GPHS) modules as the energy source and Advanced Stirling Convertors (ASCs) to convert heat into electrical energy, and is being developed by Lockheed Martin under contract to the Department of Energy. Achieving flight status mandates that the ASCs satisfy design as well as flight requirements to ensure reliable operation during launch. To meet these launch requirements, GRC performed a series of quasi-static mechanical tests simulating the pressure, thermal, and external loading conditions that will be experienced by an ASC-E2 heater head assembly. These mechanical tests were collectively referred to as "lateral load tests" since a primary external load lateral to the heater head longitudinal axis was applied in combination with the other loading conditions. The heater head was subjected to the operational pressure, axial mounting force, thermal conditions, and axial and lateral launch vehicle acceleration loadings. To permit reliable prediction of the heater head s structural performance, GRC completed Finite Element Analysis (FEA) computer modeling for the stress, strain, and deformation that will result during launch. The heater head lateral load test directly supported evaluation of the analysis and validation of the design to meet launch requirements. This paper provides an overview of each element within the test and presents assessment of the modeling as well as experimental results of this task.
Author
STIRLING CYCLE; RADIOISOTOPE HEAT SOURCES; PISTON ENGINES; LOAD TESTS; LAUNCH VEHICLES; STATIC TESTS
20110023436 NASA Glenn Research Center, Cleveland, OH, United States
Numerical Studies of an Array of Fluidic Diverter Actuators for Flow Control
Gokoglu, Suleyman A.; Kuczmarski, Maria A.; Culley, Dennis E.; Raghu, Surya; November 2011; In English; 41st Fluid Dynamics Conference and Exhibit, 27-30 Jun. 2011, Honolulu, HI, United States; Original contains color illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.17.13.01
Report No.(s): NASA/TM-2011-217259; AIAA Paper 2011-3100; E-18014; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023436
In this paper, we study the effect of boundary conditions on the behavior of an array of uniformly-spaced fluidic diverters with an ultimate goal to passively control their output phase. This understanding will aid in the development of advanced designs of actuators for flow control applications in turbomachinery. Computations show that a potential design is capable of generating synchronous outputs for various inlet boundary conditions if the flow inside the array is initiated from quiescence. However, when the array operation is originally asynchronous, several approaches investigated numerically demonstrate that re-synchronization of the actuators in the array is not practical since it is very sensitive to asymmetric perturbations and imperfections. Experimental verification of the insights obtained from the present study is currently being pursued.
Author
ACTUATORS; BOUNDARY CONDITIONS; TURBOMACHINERY; FLUIDICS; SYNCHRONISM; PERTURBATION
20110023437 NASA Goddard Space Flight Center, Greenbelt, MD, United States
GRBs in the Era of Swift and Fermi
Racusin, Judy; October 24, 2011; In English; 2011 Time Domain Astrophysics with Swift (TDASwift), 24-26 Oct. 2011, Clemson, SC, United States
Report No.(s): GSFC.ABS.5423.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023437
Utilizing both Swift and Fermi to study GRBs provides us with a unique broad spectral and temporal window into both prompt emission and afterglow studies. Swift has provided key information from GRB follow-up of LAT detected bursts) that has led to ground-based redshift measurements and afterglow broadband light curves and SEDs. We study the X-ray and optical afterglows of Fermi-LAT detected bursts in the context of the hundreds of GRBs discovered by Swift over the last 7 years) in order to better understand the origin of the high-energy gamma-rays. We also briefly describe the efforts to best facilitate joint Swift-Fermi observations. These initial results demonstrate the synergy between Swift and Fermi) and hint at the many interesting discoveries to come.
Author
GAMMA RAY BURSTS; X RAY OPTICS; RED SHIFT
20110023438 NASA Goddard Space Flight Center, Greenbelt, MD, United States
A Scientific Revolution: The Hubble and James Webb Space Telescopes
Gardner, Jonathan P.; November 15, 2011; In English
Report No.(s): GSFC.ABS.5425.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023438
Astronomy is going through a scientific revolution, responding to a flood of data from the Hubble Space Telescope, other space missions, and large telescopes on the ground. In this talk, I will discuss some of the most important astronomical discoveries of the last 10 years, and the role that space telescopes have played in those discoveries. The next decade looks equally bright with the newly refurbished Hubble and the promise of its successor, the James Webb Space Telescope. I will describe how Hubble was upgraded and how and why we are building Webb.
Author
ASTRONOMY; HUBBLE SPACE TELESCOPE; JAMES WEBB SPACE TELESCOPE
20110023439 NASA Glenn Research Center, Cleveland, OH, United States
An Evaluation of Performance Metrics for High Efficiency Tube-and-Wing Aircraft Entering Service in 2030 to 2035
Perkins, H. Douglas; Wilson, Jack; Raymer, Daniel P.; November 2011; In English; Original contains color illustrations
Contract(s)/Grant(s): WBS 599489.02.07.03.03.12.02
Report No.(s): NASA/TM-2011-217264; E-18020; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023439
An analysis of basic vehicle characteristics required to meet the Fundamental Aeronautics Program s 70 percent energy consumption reduction goal for commercial airliners in the 2030 to 2035 timeframe was conducted. A total of 29 combinations of vehicle parasitic drag coefficient, vehicle induced drag coefficient, vehicle empty weight and engine Specific Fuel Consumption were used to create sized tube-and-wing vehicle models. The mission fuel burn for each of these sized vehicles was then compared to a baseline current technology vehicle. A response surface equation was generated of fuel burn reduction as a function of the four basic vehicle performance metrics, so that any values of the performance metrics up to a 50 percent reduction could be used to estimate fuel burn reduction of tube-and-wing aircraft for future studies.
Author
AERODYNAMIC COEFFICIENTS; COMMERCIAL AIRCRAFT; ENERGY CONSUMPTION; FUEL CONSUMPTION; AERODYNAMIC DRAG; INDUCED DRAG
20110023441 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Watching Galaxy Evolution in High Definition
Rigby, Jane; October 16, 2011; In English
Report No.(s): GSFC.ABS.5362.2011; GSFC.ABS.5399.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023441
As Einstein predicted, mass deflects light. In hundreds of known cases, "gravitational lenses" have deflected, distorted, and amplified images of galaxies or quasars behind them. As such, gravitational lensing is a way to "cheat" at studying how galaxies evolve, because lensing can magnify galaxies by factors of 10--100 times, transforming them from objects we can barely detect to bright objects we can study in detail. I'll summarize new results from a comprehensive program, using multi-wavelength, high-quality spectroscopy, to study how galaxies formed stars at redshifts of 1--3, the epoch when most of the Universe's stars were formed.
Author
GALACTIC EVOLUTION; SPECTROSCOPY; GRAVITATIONAL LENSES; UNIVERSE; IMAGES
20110023443 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Global Precipitation Measurement (GPM) Mission: Overview and U.S. Status
Hou, Arthur Y.; Azarbarzin, Ardeshir A.; Kakar, Ramesh K.; Neeck, Steven; September 28, 2011; In English; 5th Workshop of Satellite Data Application for Global Environmental Monitoring, 28-30 Sep. 2011, Kyoung-Ju, Korea, Republic of
Report No.(s): GSFC.ABS.5369.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023443
The Global Precipitation Measurement (GPM) Mission is an international satellite mission specifically designed to unify and advance precipitation measurements from a constellation of research and operational microwave sensors. Building upon the success of the U.S.-Japan Tropical Rainfall Measuring Mission (TRMM), the National Aeronautics and Space Administration (NASA) of the United States and the Japan Aerospace and Exploration Agency (JAXA) will deploy in 2013 a GPM "Core" satellite carrying a KulKa-band Dual-frequency Precipitation Radar (DPR) and a conical-scanning multi-channel (10-183 GHz) GPM Microwave Imager (GMI) to establish a new reference standard for precipitation measurements from space. The combined active/passive sensor measurements will also be used to provide common database for precipitation retrievals from constellation sensors. For global coverage, GPM relies on existing satellite programs and new mission opportunities from a consortium of partners through bilateral agreements with either NASA or JAXA. Each constellation member may have its unique scientific or operational objectives but contributes microwave observations to GPM for the generation and dissemination of unified global precipitation data products. In addition to the DPR and GMI on the Core Observatory, the baseline GPM constellation consists of the following sensors: (1) Special Sensor Microwave Imager/Sounder (SSMIS) instruments on the U.S. Defense Meteorological Satellite Program (DMSP) satellites, (2) the Advanced Microwave Scanning Radiometer- 2 (AMSR-2) on the GCOM-Wl satellite of JAXA, (3) the Multi-Frequency Microwave Scanning Radiometer (MADRAS) and the multi-channel microwave humidity sounder (SAPHIR) on the French-Indian Megha-Tropiques satellite, (4) the Microwave Humidity Sounder (MHS) on the National Oceanic and Atmospheric Administration (NOAA)-19, (5) MHS instruments on MetOp satellites launched by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), (6) the Advanced Technology Microwave Sounder (ATMS) on the National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project (NPP), (7) ATMS instruments on the NOAA-NASA Joint Polar Satellite System (JPSS) satellites, and (8) a microwave imager under planning for the Defense Weather Satellite System (DWSS).
Author
PRECIPITATION MEASUREMENT; TRMM SATELLITE; METEOROLOGICAL SATELLITES; METEOROLOGICAL RADAR; MICROWAVE IMAGERY; HUMIDITY; MICROWAVE SOUNDING
20110023444 NASA Goddard Space Flight Center, Greenbelt, MD, United States
A Herschel-Resolved Debris Disk Around the Nearby G Star HIP 32480
Stapelfeldt, K.; [2011]; In English; 219th American Astronomical Society Conference, 8-12 Jan. 2012, Austin, TX, United States
Report No.(s): GSFC.ABS.5427.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023444
The Herschel Space Observatory is providing unprecedented sensitivity and angular resolution in the far-infrared. The DUNES Key Project (DUst around NEarby Stars, PI Carlos Eiroa) has finished its survey of 133 FGK stars within 25 pc of the Sun using the PACS photometer at 100 and 160 microns. We report the detection of a resolved debris ring around HIP 32480, a G0 star 16.5 parsecs distant. The ring is almost 300 AU in diameter and inclined 30 degrees from edge-on. We present a thermal emission model for the system that fits the Spitzer spectroscopy and Herschel images of the system. We find a minimum grainsize of approximately 4 microns in the main ring and a distinct warm dust population interior to it. Faint detached emission features just outside the ring may trace a separate, more distant ring in the system. The non-detection of the ring in archival HST/ACS coronagraphic images limits the dust grain albedo in the ring to be no more than 10%.
Author
THERMAL EMISSION; SPACE DEBRIS; STELLAR ENVELOPES; G STARS
20110023445 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Dust and Other Recent Discoveries in SN 1987A
Sonneborn, George; November 02, 2011; In English; NASA Ames Colloquium, 2 Nov. 2011, Mountain View, CA, United States
Report No.(s): GSFC.ABS.5429.2011; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023445
Supernova 1987 A in the Large Magellanic Cloud is one of the most intensively studied objects in the universe and a Rosetta Stone for understanding the explosions of massive stars. Now almost 25 years old, SN 1987 A is a very young supernova remnant, a phase previously unobserved in any other supernova. In this talk I will discuss recent observations from the far ultraviolet to the far-infrared with HST, the VLT, and the Herschel Space Observatory. These data reveal new insights into the composition, geometry, and heating of the explosion debris, the shock interaction with circumstellar material, and dust in the SN 1987 A system.
Author
MASSIVE STARS; SUPERNOVA REMNANTS; COSMIC DUST; STELLAR PHYSICS; SPACEBORNE ASTRONOMY; SUPERNOVA 1987A
20110023446 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The SEEDS of Planet Formation: Observations of Transitional Disks
Grady, Carol; October 05, 2011; In English
Contract(s)/Grant(s): NNG09EP47P
Report No.(s): GSFC.ABS.5454.2011; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023446
As part of its 5-year study, the Strategic Exploration of Exoplanets and Disk Systems (SEEDS) has already observed a number of YSOs with circumstellar disks, including 13 0.5- 8 Myr old A-M stars with indications that they host wide gaps or central cavities in their circumstellar disks in millimeter or far-IR observations, or from deficits in warm dust thermal emission. For 8 of the disks, the 0.15" inner working angle of HiCIAO+A0188 samples material in the millimeter or mid-IR identified cavity. In one case we reprt detection of a previously unrecognized wide gap. For the remaining 4 stars, the SEEDS data sample the outer disk: in 3 cases, we present the first NIR imagery of the disks. The data for the youngest sample members (less than 1-2 Myr) closely resemble coeval primordial disks. After approximately 3 Myr, the transitional disks show a wealth of structure including spiral features, rings, divots, and in some cases, largely cleared gaps in the disks which are not seen in coeval primordial disks. Some of these structural features are predicted consequences of lovianmass planets having formed in the disk, while others are novel features. We discuss the implications for massive planet formation timescales and mechanisms.
Author
EXTRASOLAR PLANETS; PLANETARY EVOLUTION; PROTOPLANETARY DISKS; COSMOLOGY
20110023451 NASA, Washington, DC United States
Micro spectrometer for parallel light and method of use
Park, Yeonjoon, Inventor; Choi, Sang H., Inventor; King, Glen C., Inventor; Elliott, James R., Inventor; November 15, 2011; In English
Patent Info.: July 2, 2009US-Patent-8,059,273; US-Patent-Appl-SN-12/496,788
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023451
A spectrometer system includes an optical assembly for collimating light, a micro-ring grating assembly having a plurality of coaxially-aligned ring gratings, an aperture device defining an aperture circumscribing a target focal point, and a photon detector. An electro-optical layer of the grating assembly may be electrically connected to an energy supply to change the refractive index of the electro-optical layer. Alternately, the gratings may be electrically connected to the energy supply and energized, e.g., with alternating voltages, to change the refractive index. A data recorder may record the predetermined spectral characteristic. A method of detecting a spectral characteristic of a predetermined wavelength of source light includes generating collimated light using an optical assembly, directing the collimated light onto the micro-ring grating assembly, and selectively energizing the micro-ring grating assembly to diffract the predetermined wavelength onto the target focal point, and detecting the spectral characteristic using a photon detector.
Official Gazette of the U.S. Patent and Trademark Office
COLLIMATION; SPECTROMETERS; MINIATURIZATION; LIGHT (VISIBLE RADIATION)
Additions to the NASA Aeronautics and Space Database as of 12/21/2011
20110023452 Rochester Univ., NY, United States
Fast Approximate Broadband Phase Retrieval for Segmented Systems
Jurling, Alden S.; Fienup, James R.; October 16, 2011; In English; Paper FThD1 Frontiers in Optics 2011, 16-20 Oct. 2011, San Jose, CA, United States; Original contains color illustrations
Report No.(s): GSFC.CPR.5504.2011; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023452
Broadband phase retrieval needed when: a) Narrow spectral filters are unavailable. b) Dim sources. c) Low throughput due to misalignment. d) Short exposures times. i.e., Pointing instability (space); and Atmospheric instability (ground based AO). Traditional approach is computationally burdensome for extreme bandwidths. Approximate approach: a) Substitute monochromatic model. b) Blur model and data. Test case performance: a) approx.270x reduction in computational cost for FGS-like test case. b) Good accuracy for monolithic system. c) Acceptable accuracy for segmented systems. i.e., Reduced by diffraction and Reduced by higher order segment model.
Author
BANDWIDTH; BROADBAND; DIFFRACTION; MISALIGNMENT; EXPOSURE
20110023453 NASA Goddard Space Flight Center, Greenbelt, MD, United States
SPASE: The Connection Among Solar and Space Physics Data Centers
Thieman, James R.; King, Todd A.; Roberts, D. Aaron; September 03, 2011; In English; 1st International Council of Scientific Unions (ICSU) World Data Systems Conference, NCTS#15622-11, 3-6 Sep. 2011, Kyoto, Japan; Original contains color illustrations
Report No.(s): GSFC.CPR.5516.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023453
The Space Physics Archive Search and Extract (SPASE) project is an international collaboration among Heliophysics (solar and space physics) groups concerned with data acquisition and archiving. Within this community there are a variety of old and new data centers, resident archives, "virtual observatories", etc. acquiring, holding, and distributing data. A researcher interested in finding data of value for his or her study faces a complex data environment. The SPASE group has simplified the search for data through the development of the SPASE Data Model as a common method to describe data sets in the various archives. The data model is an XML-based schema and is now in operational use. There are both positives and negatives to this approach. The advantage is the common metadata language enabling wide-ranging searches across the archives, but it is difficult to inspire the data holders to spend the time necessary to describe their data using the Model. Software tools have helped, but the main motivational factor is wide-ranging use of the standard by the community. The use is expanding, but there are still other groups who could benefit from adopting SPASE. The SPASE Data Model is also being expanded in the sense of providing the means for more detailed description of data sets with the aim of enabling more automated ingestion and use of the data through detailed format descriptions. We will discuss the present state of SPASE usage and how we foresee development in the future. The evolution is based on a number of lessons learned - some unique to Heliophysics, but many common to the various data disciplines.
Author
SOLAR PHYSICS; ATMOSPHERIC PHYSICS; INFORMATION SYSTEMS; METADATA; DATA ACQUISITION
20110023454 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Inspections for Systems and Software
Mastrofini, Manuel; Diep, Madeline; Shull, Forrest; Seaman, Carolyn; Godfrey, Sally; October 24, 2011; In English; NDIA 14th Annual System Engineering Conference, 24-27 Oct. 2011, San Diego, CA, United States; Original contains color illustrations
Contract(s)/Grant(s): NNX08AZ60G
Report No.(s): GSFC.CPR.5456.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023454
No abstract available
INSPECTION; SOFTWARE ENGINEERING; FAULT DETECTION; SOFTWARE RELIABILITY; COMPUTER SYSTEMS PERFORMANCE; PROGRAM VERIFICATION (COMPUTERS); RELIABILITY ANALYSIS; CHECKOUT
20110023455 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Capacitor Test, Evaluation. and Modeling Within NASA Electronic Parts and Packaging (NEPP) Program. "Why Ceramic Capacitors Fracture During Manual Soldering and How to Avoid Failures"
Teverovsky, Alexander; June 2011; In English; NASA Electronic Parts and Packaging (NEPP) Program Electronic Technology Workshop (ETW) 2011, June 2011, Greenbelt, MD, United States; Original contains color illustrations
Report No.(s): GSFC.DPW.5350.2011; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023455
Presentation discusses: (1) Why Multi-Layer Ceramic Capacitors(MLCCs) crack during manual soldering? Workmanship and parts issues. (2) Do existing qualification requirements assure crack-free soldering? MIL-spec Thermal Shock (TS) testing. MIL-spec Resistance to Soldering Heat (RSH) test. (3) What test can assure reliable soldering? Mechanical characteristics of ceramics. Comparison of three TS techniques: LND, TSD, and IWT. (4) Simulation of TS conditions.
Derived from text
CAPACITORS; CERAMICS; CRACKS; ELECTRONIC PACKAGING; SHOCK TESTS; SOLDERING; THERMAL SHOCK; MODELS
20110023456 NASA Goddard Space Flight Center, Greenbelt, MD, United States
A Conjugate Study of Mean Winds and Planetary Waves Employing Enhanced Meteor Radars at Rio Grande, Argentina (53.8degS) and Juliusruh, Germany (54.6degN)
Fritts, D. C.; Imura, H.; Lieberman, R.; Janches, D.; Singer, W.; May 25, 2011; In English; Original contains color illustrations
Contract(s)/Grant(s): NSF ATM-0634650
Report No.(s): GSFC.JA.5332.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023456
Two meteor radars with enhanced power and sensitivity and located at closely conjugate latitudes (54.6degN and 53.8degS) are employed for inter-hemispheric comparisons of mean winds and planetary wave structures. Our study uses data from June 2008 through May 2010 during which both radars provided nearly continuous wind measurements from approx.80 to 100 km. Monthly mean winds at 53.8degS exhibit a somewhat stronger westward mean zonal jet in spring and early summer at lower altitudes and no westward monthly mean winds at higher altitudes. In contrast, westward mean winds of approx.5-10 m/s at 54.6degN extend to above 96 km during late winter and early spring each year. Equatorward monthly mean winds extend approximately from spring to fall equinox at both latitudes, with amplitudes of approx.5-10 m/s and more rapid decreases in amplitude at 54.6degN at higher altitudes. Meridional mean winds are more variable at both latitudes during fall and winter, with both poleward and equatorward monthly means indicating longer-period variability. Planetary waves seen in the 2-day mean data are episodic and variable at both sites, exhibit dominant periodicities of approx.8-10 and 16-20 days and are more confined to late fall and winter at 54.6degN. At both latitudes, planetary waves in the two period bands coincide closely in time and exhibit similar horizontal velocity covariances that are positive (negative) at 54.6degN (53.8degS) during peak planetary wave responses.
Author
METEOROIDS; PLANETARY WAVES; WIND MEASUREMENT; CONJUGATES; MERIDIONAL FLOW; PERIODIC VARIATIONS; WIND (METEOROLOGY)
20110023457 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Ethane in Planetary and Cometary Atmospheres: Transmittance and Fluorescence Models of the nu7 Band at 3.3 Micrometers
Villanueva, G. L.; Mumma, M. J.; Magee-Sauer, K.; Journal of Geophysical Research - Planets; August 30, 2011; vol. Volume 116; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): RTOP 344-32-07; RTOP 344-53-51
Report No.(s): GSFC.JA.5345.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1029/2010JE003794
Ethane and other hydrocarbon gases have strong rovibrational transitions in the 3.3 micron spectral region owing to C-H, CH2, and CH3 vibrational modes, making this spectral region prime for searching possible biomarker gases in extraterrestrial atmospheres (e.g., Mars, exoplanets) and organic molecules in comets. However, removing ethane spectral signatures from high-resolution terrestrial transmittance spectra has been imperfect because existing quantum mechanical models have been unable to reproduce the observed spectra with sufficient accuracy. To redress this problem, we constructed a line-by-line model for the n7 band of ethane (C2H6) and applied it to compute telluric transmittances and cometary fluorescence efficiencies. Our model considers accurate spectral parameters, vibration-rotation interactions, and a functional characterization of the torsional hot band. We integrated the new band model into an advanced radiative transfer code for synthesizing the terrestrial atmosphere (LBLRTM), achieving excellent agreement with transmittance data recorded against Mars using three different instruments located in the Northern and Southern hemispheres. The retrieved ethane abundances demonstrate the strong hemispheric asymmetry noted in prior surveys of volatile hydrocarbons. We also retrieved sensitive limits for the abundance of ethane on Mars. The most critical validation of the model was obtained by comparing simulations of C2H6 fluorescent emission with spectra of three hydrocarbon-rich comets: C/2004 Q2 (Machholz), 8P/Tuttle, and C/2007 W1 (Boattini). The new model accurately describes the complex emission morphology of the nu7 band at low rotational temperatures and greatly increases the confidence of the retrieved production rates (and rotational temperatures) with respect to previously available fluorescence models.
Author
ETHANE; EXTRASOLAR PLANETS; COMETS; SPECTRAL SIGNATURES; RADIATIVE TRANSFER; METHYL COMPOUNDS; HYDROCARBONS; BIOMARKERS
20110023458 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Inter-Annual and Decadal Changes in Tropospheric and Stratospheric Ozone
Ziemke, Jr. R.; Chandra, S.; September 2011; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NNH07ZDA001N-AST
Report No.(s): GSFC.JA.5352.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023458
Ozone data beginning October 2004 from the Aura Ozone Monitoring Instrument (OMI) and Aura Microwave Limb Sounder (MLS) are used to evaluate the accuracy of the Cloud slicing technique in effort to develop long data records of tropospheric and stratospheric ozone and studying their long-term changes. Using this technique, we have produced a 32-year (1979-2010) long record of tropospheric and stratospheric ozone from the combined Total Ozone Mapping Spectrometer (Toms) and OMI. The analyses of these time series suggest that the quasi-biennial oscillation (QBO) is the dominant source of inter-annual changes of 30-40 Dobson Units (DU). Tropospheric ozone also indicates a QBO signal in the peak to peak changes varying from 2 to 7 DU. Decadal changes in global stratospheric ozone indicate a turnaround in ozone loss around mid 1990's with most of these changes occurring in the Northern Hemisphere from the subtropics to high latitudes. The trend results are generally consistent with the prediction of chemistry climate models which include the reduction of ozone destroying substances beginning in the late 1980's mandated by the Montreal Protocol.
Author
ATMOSPHERIC COMPOSITION; OZONE; PERIODIC VARIATIONS; STRATOSPHERE; TIME SERIES ANALYSIS; TROPOSPHERE; OZONE DEPLETION
20110023459 Science Systems and Applications, Inc., Lanham, MD, United States
Direct Observations of PMC Local Time Variations by Aura OMI
DeLand, Matthew T.; Shettle, Eric P.; Thomas, Gary E.; Olivero, John J.; Journal of Atmospheric and Solar-Terrestrial Physics; November 21, 2010; ISSN 1364-6826; vol. Volume 73; issue Issues 14-15; pp. 2049-206; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NNH08CD48C
Report No.(s): GSFC.JA.5353.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1016/j.jastp.2010.11.019
The Ozone Monitoring Instrument (OMI) on the Aura satellite obtains unique measurements for polar mesospheric cloud (PMC) analysis. Its wide cross-track viewing swath and high along-track spatial resolution makes it possible to directly evaluate PMC occurrence frequency and brightness variations between 6S" and 8S' latitude as a function of local time over a 12-14 h continuous period. OMI PMC local time variations are closely coupled to concurrent variations in measurement scattering angle, so that ice phase function effects must be considered when interpreting the observations. Two different phase functions corresponding to bright and faint clouds are examined in this analysis. OMI observations show maximum frequency and albedo values at 8-10 h local time in the Northern Hemisphere, with decreasing amplitude at higher latitudes. Southern Hemisphere values reach a minimum at 18-20 h LT. Larger variations are seen in Northern Hemisphere data. No statistically significant longitudinal dependence was seen.
Author
NOCTILUCENT CLOUDS; TIME DEPENDENCE; SWATH WIDTH; SOUTHERN HEMISPHERE; SATELLITE OBSERVATION; SPATIAL RESOLUTION; BRIGHTNESS
20110023461 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Long-Duration Human Habitation Beyond Low-Earth Orbit: Why is the Near Future Critical?
Thronson, Harley A.; Lester, Daniel; Hatfield, C. A.; January 2011; In English; Original contains black and white illustrations
Report No.(s): GSFC.JA.5363.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023461
For more than a decade, habitation systems capable of comfortable human occupation and effective operations beyond low-Earth orbit (LEO) for more than a few weeks have been a priority recommendation to NASA. This capability is a lynch pin for human exploration beyond the Earth-Moon system. Here we describe briefly some relevant concepts and discuss justifications in the current political and financial environment for why near-term human habitation systems beyond LEO is an imperative.
Author
EARTH-MOON SYSTEM; LOW EARTH ORBITS; MANAGEMENT PLANNING; HABITABILITY; INTERNATIONAL SPACE STATION
20110023463 Ophir Corp., Littleton, CO United States
Optical air data systems and methods
Caldwell, Loren M., Inventor; Tang, Shoou-Yu, Inventor; O'Brien, Martin J., Inventor; November 29, 2011; In English
Contract(s)/Grant(s): NAS4-02043
Patent Info.: November 10, 2008US-Patent-8,068,216; US-Patent-Appl-SN-12/268,072
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023463
A method for remotely sensing air outside a moving aircraft includes generating laser radiation within a swept frequency range. A portion of the laser radiation is projected from the aircraft into the air to induce scattered laser radiation. Filtered scattered laser radiation, filtered laser radiation, and unfiltered laser radiation are detected. At least one actual ratio is determined from data corresponding to the filtered scattered laser radiation and the unfiltered laser radiation. One or more air parameters are determined by correlating the actual ratio to at least one reference ratio.
Official Gazette of the U.S. Patent and Trademark Office
AIR DATA SYSTEMS; REMOTE SENSING; DETECTION; LASER BEAMS
20110023464 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Concerning the Motion and Orientation of Flux Transfer Events Produced by Component and Antiparallel Reconnection
Sibeck, D. G.; Lin, R.-Q.; Journal of Geophysical Research - Space Physics; July 09, 2011; vol. Volume 116; In English; Original contains color illustrations
Report No.(s): GSFC.JA.5091.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023464
http://dx.doi.org/10.1029/2011JA016560
We employ the Cooling et al. (2001) model to predict the location, orientation, motion, and signatures of flux transfer events (FTEs) generated at the solstices and equinoxes along extended subsolar component and high ]latitude antiparallel reconnection curves for typical solar wind plasma conditions and various interplanetary magnetic field (IMF) strengths and directions. In general, events generated by the two mechanisms maintain the strikingly different orientations they begin with as they move toward the terminator in opposite pairs of magnetopause quadrants. The curves along which events generated by component reconnection form bow toward the winter cusp. Events generated by antiparallel reconnection form on the equatorial magnetopause during intervals of strongly southward IMF orientation during the equinoxes, form in the winter hemisphere and only reach the dayside equatorial magnetopause during the solstices when the IMF strength is very large and the IMF points strongly southward, never reach the equatorial dayside magnetopause when the IMF has a substantial dawnward or duskward component, and never reach the equatorial flank magnetopause during intervals of northward and dawnward or duskward IMF orientation. Magnetosheath magnetic fields typically have strong components transverse to events generated by component reconnection but only weak components transverse to the axes of events generated by antiparallel reconnection. As a result, much stronger bipolar magnetic field signatures normal to the nominal magnetopause should accompany events generated by component reconnection. The results presented in this paper suggest that events generated by component reconnection predominate on the dayside equatorial and flank magnetopause for most solar wind conditions.
Author
MAGNETIC FLUX; FLUX TRANSFER EVENTS; PLASMA INTERACTIONS; MAGNETOPAUSE; BIPOLARITY; WIND DIRECTION; WIND VELOCITY; SOLAR WIND; MAGNETIC FIELDS
20110023465 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Characterization of Terrestrial Water Dynamics in the Congo Basin Using GRACE and Satellite Radar Altimetry
Lee, Hyongki; Beighley, R. Edward; Alsdorf, Douglas; Jung, Hahn Chul; Shum, C. K.; Duan, Jianbin; Guo, Junyi; Yamazaki, Dai; Andreadis, Konstantinos; January 2011; In English; Original contains color illustrations
Report No.(s): GSFC.JA.5385.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023465
http://dx.doi.org/10.1016/j.rse.2011.08.015
The Congo Basin is the world's third largest in size (approx.3.7 million sq km), and second only to the Amazon River in discharge (approx.40,200 cu m/s annual average). However, the hydrological dynamics of seasonally flooded wetlands and floodplains remains poorly quantified. Here, we separate the Congo wetland into four 3deg 3deg regions, and use remote sensing measurements (i.e., GRACE, satellite radar altimeter, GPCP, JERS-1, SRTM, and MODIS) to estimate the amounts of water filling and draining from the Congo wetland, and to determine the source of the water. We find that the amount of water annually filling and draining the Congo wetlands is 111 cu km, which is about one-third the size of the water volumes found on the mainstem Amazon floodplain. Based on amplitude comparisons among the water volume changes and timing comparisons among their fluxes, we conclude that the local upland runoff is the main source of the Congo wetland water, not the fluvial process of river-floodplain water exchange as in the Amazon. Our hydraulic analysis using altimeter measurements also supports our conclusion by demonstrating that water surface elevations in the wetlands are consistently higher than the adjacent river water levels. Our research highlights differences in the hydrology and hydrodynamics between the Congo wetland and the mainstem Amazon floodplain.
Author
FLOOD PLAINS; REMOTE SENSING; HYDRODYNAMICS; HYDROLOGY; WETLANDS; MODIS (RADIOMETRY); SATELLITE ALTIMETRY; DRAINAGE
20110023466 NASA Goddard Space Flight Center, Greenbelt, MD, United States
A Comparison of Methods for a Priori Bias Correction in Soil Moisture Data Assimilation
Kumar, Sujay V.; Reichle, Rolf H.; Harrison, Kenneth W.; Peters-Lidard, Christa D.; Yatheendradas, Soni; Santanello, Joseph A.; September 30, 2011; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): AIST-08-077
Report No.(s): GSFC.JA.5386.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023466
Data assimilation is being increasingly used to merge remotely sensed land surface variables such as soil moisture, snow and skin temperature with estimates from land models. Its success, however, depends on unbiased model predictions and unbiased observations. Here, a suite of continental-scale, synthetic soil moisture assimilation experiments is used to compare two approaches that address typical biases in soil moisture prior to data assimilation: (i) parameter estimation to calibrate the land model to the climatology of the soil moisture observations, and (ii) scaling of the observations to the model s soil moisture climatology. To enable this research, an optimization infrastructure was added to the NASA Land Information System (LIS) that includes gradient-based optimization methods and global, heuristic search algorithms. The land model calibration eliminates the bias but does not necessarily result in more realistic model parameters. Nevertheless, the experiments confirm that model calibration yields assimilation estimates of surface and root zone soil moisture that are as skillful as those obtained through scaling of the observations to the model s climatology. Analysis of innovation diagnostics underlines the importance of addressing bias in soil moisture assimilation and confirms that both approaches adequately address the issue.
Author
ALGORITHMS; CLIMATOLOGY; EARTH SURFACE; SOIL MOISTURE; REMOTE SENSING; PARAMETER IDENTIFICATION; HEURISTIC METHODS; INFORMATION SYSTEMS
20110023467 Jet Propulsion Lab., California Inst. of Tech., Pasadena, CA, United States
HyspIRI Level-2 Thermal Infrared (TIR) Land Surface Temperature and Emissivity Algorithm Theoretical Basis Document
Hulley, G.; Hook, S.; May 2011; In English; Original contains color illustrations
Contract(s)/Grant(s): NAS7-03001Proj. 103932
Report No.(s): JPL-Publ-11-5; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023467
http://hdl.handle.net/2014/41904
This document outlines the theory and methodology for generating the HyspIRI TIR Level-2 land surface temperature and emissivity (LST&E) products. The LST&E products are derived from the surface radiance product that is calculated by atmospherically correcting the at-sensor radiance, making them interdependent products. LST&E products are essential for a wide range of Earth system studies.
Author
INFRARED RADIATION; RADIANCE; EMISSIVITY; LAND SURFACE TEMPERATURE; SPECTROMETERS; IMAGING SPECTROMETERS
20110023468 Princeton Univ., NJ United States
Conductive ink containing thermally exfoliated graphite oxide and method a conductive circuit using the same
Prud'Homme, Robert K., Inventor; Aksay, Ilhan A., Inventor; November 1, 2011; In English
Contract(s)/Grant(s): NCC1-02037
Patent Info.: August 19, 2008US-Patent-8,048,214; US-Patent-Appl-SN-12/194,030
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023468
A conductive ink containing a conductive polymer, wherein the conductive polymer contains at least one polymer and a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m/g, and it use in a method for making a conductive circuit.
Official Gazette of the U.S. Patent and Trademark Office
CIRCUITS; GRAPHITE; INKS; CONDUCTING POLYMERS
20110023469 NASA Marshall Space Flight Center, Huntsville, AL, United States
Improving Numerical Weather Predictions of Summertime Precipitation Over the Southeastern U.S. Through a High-Resolution Initialization of the Surface State
Case, Jonathan L.; Kumar, Sujay V.; Krikishen, Jayanthi; Jedlovec, Gary J.; January 2011; In English; Original contains color illustrations
Report No.(s): GSFC.JA.5387.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023469
http://dx.doi.org/10.1175/2011WAF2222455.1
It is hypothesized that high-resolution, accurate representations of surface properties such as soil moisture and sea surface temperature are necessary to improve simulations of summertime pulse-type convective precipitation in high resolution models. This paper presents model verification results of a case study period from June-August 2008 over the Southeastern U.S. using the Weather Research and Forecasting numerical weather prediction model. Experimental simulations initialized with high-resolution land surface fields from the NASA Land Information System (LIS) and sea surface temperature (SST) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) are compared to a set of control simulations initialized with interpolated fields from the National Centers for Environmental Prediction 12-km North American Mesoscale model. The LIS land surface and MODIS SSTs provide a more detailed surface initialization at a resolution comparable to the 4-km model grid spacing. Soil moisture from the LIS spin-up run is shown to respond better to the extreme rainfall of Tropical Storm Fay in August 2008 over the Florida peninsula. The LIS has slightly lower errors and higher anomaly correlations in the top soil layer, but exhibits a stronger dry bias in the root zone. The model sensitivity to the alternative surface initial conditions is examined for a sample case, showing that the LIS/MODIS data substantially impact surface and boundary layer properties.
Author
ATMOSPHERIC BOUNDARY LAYER; SURFACE PROPERTIES; SEA SURFACE TEMPERATURE; SOIL MOISTURE; HIGH RESOLUTION; LAND SURFACE TEMPERATURE; MODIS (RADIOMETRY); NUMERICAL WEATHER FORECASTING; RAIN; TROPICAL STORMS
20110023470 Stanford Univ., Stanford, CA United States
Semiconductor crystal high resolution imager
Levin, Craig S., Inventor; Matteson, James, Inventor; November 22, 2011; In English
Contract(s)/Grant(s): NAG5-5349
Patent Info.: September 30, 2005US-Patent-8,063,380; US-Patent-Appl-SN-11/662,870
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023470
A radiation imaging device (10). The radiation image device (10) comprises a subject radiation station (12) producing photon emissions (14), and at least one semiconductor crystal detector (16) arranged in an edge-on orientation with respect to the emitted photons (14) to directly receive the emitted photons (14) and produce a signal. The semiconductor crystal detector (16) comprises at least one anode and at least one cathode that produces the signal in response to the emitted photons (14).
Official Gazette of the U.S. Patent and Trademark Office
SEMICONDUCTORS (MATERIALS); ELECTROMAGNETIC RADIATION; PHOTONS; IMAGING TECHNIQUES; CRYSTALS; EMITTANCE
20110023471 Jet Propulsion Lab., California Inst. of Tech., Pasadena, CA, United States
Investigation of the Semicoa SCF9550 and the International Rectifier IRHM57260SE for Single-Event Gate Rupture and Single- Event Burnout
Scheick, Leif; September 2011; In English; Original contains color illustrations
Contract(s)/Grant(s): NAS7-03001WBS 939904.01.11.30
Report No.(s): JPL-Publ- 11-7; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023471
Single-event-effect test results for hi-rel total-dose-hardened power MOSFETs are presented in this report. The SCF9550 from Semicoa and the IRHM57260SE from International Rectifier were tested to NASA test condition standards and requirements. The IRHM57260SE performed much better when compared to previous testing. These initial results confirm that parts from the Temecula line are marginally comparable to the El Segundo line. The SCF9550 from Semicoa was also tested and represents the initial parts offering from this vendor. Both parts experienced single-event gate rupture (SEGR) and single-event burnout (SEB). All of the SEGR was from gate to drain.
Author
FIELD EFFECT TRANSISTORS; METAL OXIDE SEMICONDUCTORS; BURNOUT; DRAINAGE
20110023474 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Effective Tree Scattering and Opacity at L-Band
Kurum, Mehmet; O'Neill, Peggy E.; Lang, Roger H.; Joseph, Alicia T.; Cosh, Michael H.; Jackson, Thomas J.; [2011]; In English; Original contains color and black and white illustrations
Report No.(s): GSFC.JA.5391.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023474
This paper investigates vegetation effects at L-band by using a first-order radiative transfer (RT) model and truck-based microwave measurements over natural conifer stands to assess the applicability of the tau-omega) model over trees. The tau-omega model is a zero-order RT solution that accounts for vegetation effects with effective vegetation parameters (vegetation opacity and single-scattering albedo), which represent the canopy as a whole. This approach inherently ignores multiple-scattering effects and, therefore, has a limited validity depending on the level of scattering within the canopy. The fact that the scattering from large forest components such as branches and trunks is significant at L-band requires that zero-order vegetation parameters be evaluated (compared) along with their theoretical definitions to provide a better understanding of these parameters in the retrieval algorithms as applied to trees. This paper compares the effective vegetation opacities, computed from multi-angular pine tree brightness temperature data, against the results of two independent approaches that provide theoretical and measured optical depths. These two techniques are based on forward scattering theory and radar corner reflector measurements, respectively. The results indicate that the effective vegetation opacity values are smaller than but of similar magnitude to both radar and theoretical estimates. The effective opacity of the zero-order model is thus set equal to the theoretical opacity and an explicit expression for the effective albedo is then obtained from the zero- and first- order RT model comparison. The resultant albedo is found to have a similar magnitude as the effective albedo value obtained from brightness temperature measurements. However, it is less than half of that estimated using the theoretical calculations (0.5 - 0.6 for tree canopies at L-band). This lower observed albedo balances the scattering darkening effect of the large theoretical albedo with a first-order multiple-scattering contribution. The retrieved effective albedo is different from theoretical definitions and not the albedo of single forest elements anymore, but it becomes a global parameter, which depends on all the processes taking place within the canopy, including multiple-scattering.
Author
BRIGHTNESS TEMPERATURE; CANOPIES (VEGETATION); RADIATIVE TRANSFER; OPTICAL THICKNESS; FORESTS; MICROWAVES; CONIFERS; OPACITY; TREES (PLANTS)
20110023475 NASA Goddard Space Flight Center, Greenbelt, MD, United States
A First-Order Radiative Transfer Model for Microwave Radiometry of Forest Canopies at L-Band
Kurum, Mehmet; Lang, Roger H.; O'Neill, Peggy E.; Joseph, Alicia T.; Jackson, Thomas J.; Cosh, Michael H.; IEEE Transactions on Geoscience and Remote Sensing; September 09, 2011; vol. Volume 49; issue No. 9; pp. 3167-317; In English; Original contains color and black and white illustrations
Report No.(s): GSFC.JA.5390.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1109/TGRS.2010.2091139
In this study, a first-order radiative transfer (RT) model is developed to more accurately account for vegetation canopy scattering by modifying the basic Tau-Omega model (the zero-order RT solution). In order to optimally utilize microwave radiometric data in soil moisture (SM) retrievals over vegetated landscapes, a quantitative understanding of the relationship between scattering mechanisms within vegetation canopies and the microwave brightness temperature is desirable. The first-order RT model is used to investigate this relationship and to perform a physical analysis of the scattered and emitted radiation from vegetated terrain. This model is based on an iterative solution (successive orders of scattering) of the RT equations up to the first order. This formulation adds a new scattering term to the . model. The additional term represents emission by particles (vegetation components) in the vegetation layer and emission by the ground that is scattered once by particles in the layer. The model is tested against 1.4-GHz brightness temperature measurements acquired over deciduous trees by a truck-mounted microwave instrument system called ComRAD in 2007. The model predictions are in good agreement with the data, and they give quantitative understanding for the influence of first-order scattering within the canopy on the brightness temperature. The model results show that the scattering term is significant for trees and modifications are necessary to the . model when applied to dense vegetation. Numerical simulations also indicate that the scattering term has a negligible dependence on SM and is mainly a function of the incidence angle and polarization of the microwave observation. Index Terms Emission,microwave radiometry, scattering, soil, vegetation.
Author
BRIGHTNESS TEMPERATURE; CANOPIES (VEGETATION); MICROWAVE RADIOMETERS; RADIATIVE TRANSFER; SOIL MOISTURE; TEMPERATURE PROFILES; ELECTROMAGNETIC RADIATION; FORESTS
20110023476 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Impact of Conifer Forest Litter on Microwave Emission at L-Band
Kurum, Mehmet; O'Neill, Peggy E.; Lang, Roger H.; Cosh, Michael H.; Joseph, Alicia T.; Jackson, Thomas J.; September 29, 2011; In English; Original contains color and black and white illustrations
Report No.(s): GSFC.JA.5389.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023476
http://dx.doi.org/10.1109/TGRS.2011.2166272
This study reports on the utilization of microwave modeling, together with ground truth, and L-band (1.4-GHz) brightness temperatures to investigate the passive microwave characteristics of a conifer forest floor. The microwave data were acquired over a natural Virginia Pine forest in Maryland by a ground-based microwave active/passive instrument system in 2008/2009. Ground measurements of the tree biophysical parameters and forest floor characteristics were obtained during the field campaign. The test site consisted of medium-sized evergreen conifers with an average height of 12 m and average diameters at breast height of 12.6 cm. The site is a typical pine forest site in that there is a surface layer of loose debris/needles and an organic transition layer above the mineral soil. In an effort to characterize and model the impact of the surface litter layer, an experiment was conducted on a day with wet soil conditions, which involved removal of the surface litter layer from one half of the test site while keeping the other half undisturbed. The observations showed detectable decrease in emissivity for both polarizations after the surface litter layer was removed. A first-order radiative transfer model of the forest stands including the multilayer nature of the forest floor in conjunction with the ground truth data are used to compute forest emission. The model calculations reproduced the major features of the experimental data over the entire duration, which included the effects of surface litter and ground moisture content on overall emission. Both theory and experimental results confirm that the litter layer increases the observed canopy brightness temperature and obscure the soil emission.
Author
CONIFERS; FORESTS; MOISTURE CONTENT; MICROWAVE RADIOMETERS; RADIATIVE TRANSFER; SOIL MOISTURE; GROUND TRUTH
20110023477 NASA Johnson Space Center, Houston, TX, United States
Space Shuttle Guidance, Navigation, and Rendezvous Knowledge Capture Reports
Goodman, John L.; October 2011; In English
Report No.(s): JSC-66136, Revision 1; JSC-CN-24818; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023477
This document is a catalog and readers guide to lessons learned, experience, and technical history reports, as well as compilation volumes prepared by United Space Alliance personnel for the NASA/Johnson Space Center (JSC) Flight Dynamics Division.1 It is intended to make it easier for future generations of engineers to locate knowledge capture documentation from the Shuttle Program. The first chapter covers observations on documentation quality and research challenges encountered during the Space Shuttle and Orion programs. The second chapter covers the knowledge capture approach used to create many of the reports covered in this document. These chapters are intended to provide future flight programs with insight that could be used to formulate knowledge capture and management strategies. The following chapters contain descriptions of each knowledge capture report. The majority of the reports concern the Space Shuttle. Three are included that were written in support of the Orion Program. Most of the reports were written from the years 2001 to 2011. Lessons learned reports concern primarily the shuttle Global Positioning System (GPS) upgrade and the knowledge capture process. Experience reports on navigation and rendezvous provide examples of how challenges were overcome and how best practices were identified and applied. Some reports are of a more technical history nature covering navigation and rendezvous. They provide an overview of mission activities and the evolution of operations concepts and trajectory design. The lessons learned, experience, and history reports would be considered secondary sources by historians and archivists.
Derived from text
SPACE SHUTTLES; SPACE NAVIGATION; SPACECRAFT TRAJECTORIES; MANNED SPACECRAFT
20110023478 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Geoeffectiveness (D (sub st) and K (sub p)) of Interplanetary Coronal Mass Ejections During 1995-2009 and Implications for Storm Forecasting
Richardson, I. G.; Cane, H. V.; Space Weather; July 21, 2011; vol. Volume 9; issue S07005; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NNG06EO90A
Report No.(s): GSFC.JA.5401.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1029/2011SW000670
We summarize the geoeffectiveness (based on the Dst and Kp indices) of the more than 300 interplanetary coronal mass ejections (ICMEs) that passed the Earth during 1996-2009, encompassing solar cycle 23. We subsequently estimate the probability that an ICME will generate geomagnetic activity that exceeds certain thresholds of Dst or Kp, including the NOAA "G" storm scale, based on maximum values of the southward magnetic field component (Bs), the solar wind speed (V), and the y component (Ey) of the solar wind convective electric field E = -V x B, in the ICME or sheath ahead of the ICME. Consistent with previous studies, the geoeffectiveness of an ICME is correlated with Bs or Ey approx.= VBs in the ICME or sheath, indicating that observations from a solar wind monitor upstream of the Earth are likely to provide the most reliable forecasts of the activity associated with an approaching ICME. There is also a general increase in geoeffectiveness with ICME speed, though the overall event-to-event correlation is weaker than for Bs and Ey. Nevertheless, using these results, we suggest that the speed of an ICME approaching the Earth inferred, for example, from routine remote sensing by coronagraphs on spacecraft well separated from the Earth or by all-sky imagers, could be used to estimate the likely geoeffectiveness of the ICME (our "comprehensive" ICME database provides a proxy for ICMEs identified in this way) with a longer lead time than may be possible using an upstream monitor
Author
CORONAL MASS EJECTION; SOLAR CYCLES; REMOTE SENSING; SOLAR WIND; VELOCITY DISTRIBUTION; WIND VELOCITY; CORONAGRAPHS; FORECASTING; MAGNETIC FIELDS; GEOMAGNETISM
20110023479 NASA Johnson Space Center, Houston, TX, United States
History of Space Shuttle Rendezvous
Goodman, John L.; October 2011; In English; Original contains color illustrations
Report No.(s): JSC-63400, Revision 3; JSC-CN-24483; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023479
This technical history is intended to provide a technical audience with an introduction to the rendezvous and proximity operations history of the Space Shuttle Program. It details the programmatic constraints and technical challenges encountered during shuttle development in the 1970s and over thirty years of shuttle missions. An overview of rendezvous and proximity operations on many shuttle missions is provided, as well as how some shuttle rendezvous and proximity operations systems and flight techniques evolved to meet new programmatic objectives. This revised edition provides additional information on Mercury, Gemini, Apollo, Skylab, and Apollo/Soyuz. Some chapters on the Space Shuttle have been updated and expanded. Four special focus chapters have been added to provide more detailed information on shuttle rendezvous. A chapter on the STS-39 mission of April/May 1991 describes the most complex deploy/retrieve mission flown by the shuttle. Another chapter focuses on the Hubble Space Telescope servicing missions. A third chapter gives the reader a detailed look at the February 2010 STS-130 mission to the International Space Station. The fourth chapter answers the question why rendezvous was not completely automated on the Gemini, Apollo, and Space Shuttle vehicles.
Derived from text
PROXIMITY; SPACE SHUTTLE MISSIONS; SPACE SHUTTLE ORBITERS; SPACE SHUTTLES; EARTH ORBITAL RENDEZVOUS; SPACECRAFT DOCKING; SPACE RENDEZVOUS
20110023480 NASA Johnson Space Center, Houston, TX, United States
Comparison of Four Strong Acids on the Precipitation Potential of Gypsum in Brines During Distillation of Pretreated, Augmented Urine
Muirhead, Dean; [2011]; In English; 42nd International Conference on Environmental Systems, 15-19 Jul. 2012, San Diego, CA, United States
Report No.(s): JSC-CN-25103; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023480
Two batches of nominally pretreated and augmented urine were prepared with the baseline pretreatment formulation of sulfuric acid and chromium trioxide. The urine was augmented with inorganic salts and organic compounds in order to simulate a urinary ionic concentrations representing the upper 95 percentile on orbit. Three strong mineral acids: phosphoric, hydrochloric, and nitric acid, were substituted for the sulfuric acid for comparison to the baseline sulfuric acid pretreatment formulation. Three concentrations of oxidizer in the pretreatment formulation were also tested. Pretreated urine was distilled to 85% water recovery to determine the effect of each acid and its conjugate base on the precipitation of minerals during distillation. The brines were analyzed for calcium and sulfate ion, total, volatile, and fixed suspended solids. Test results verified that substitution of phosphoric, hydrochloric, or nitric acids for sulfuric acid would prevent the precipitation of gypsum up to 85% recovery from pretreated urine representing the upper 95 percentile calcium concentration on orbit.
Author
BRINES; DISTILLATION; GYPSUM; URINE; WATER RECLAMATION; PRETREATMENT; ACIDS
20110023481 NASA Johnson Space Center, Houston, TX, United States
Advanced Spacesuit Portable Life Support System Oxygen Regulator Development and Testing
Campbell, Colin; Vogel, Matt R.; Watts, Carly; [2011]; In English; 42nd International Conference on Environmental Systems, 15-19 Jul. 2012, San Diego, CA, United States
Contract(s)/Grant(s): WBS 780896.04.10.04.01.03.10
Report No.(s): JSC-CN-25110; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023481
The advanced spacesuit portable life support system (PLSS) oxygen regulators represent an evolutionary approach to regulator development. Several technology development prototypes have been produced that borrow much of the mechanical regulator design from the well proven Shuttle/ISS Extravehicular Mobility Unit (EMU) Secondary Oxygen Regulator, but incorporate a motor-settable pressure set-point feature that facilitates significantly greater operational flexibility. For example, this technology would enable EVA to begin at a higher suit pressure, which would reduce pre-breathe time, and then slowly step down to a lower pressure to increase suit mobility for the duration of the EVA. Comprehensive testing of the prototypes was performed on the component level as well as part of the PLSS 1.0 system level testing. Results from these tests characterize individual prototype performance and demonstrate successful operation during multiple nominal and contingency EVA modes
Author
SPACE SUITS; PORTABLE LIFE SUPPORT SYSTEMS; OXYGEN REGULATORS; EXTRAVEHICULAR ACTIVITY; EXTRAVEHICULAR MOBILITY UNITS; SYSTEMS ENGINEERING
20110023482 NASA Johnson Space Center, Houston, TX, United States
Advanced EMU Portable Life Support System (PLSS) and Shuttle/ISS EMU Schematics, A Comparison
Campbell, Colin; [2011]; In English; 42nd International Conference on Environmental Systems, 15-19 Jul. 2012, San Diego, CA, United States
Contract(s)/Grant(s): WBS 780896.04.10.04.01.03.10
Report No.(s): JSC-CN-25112; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023482
In order to be able to adapt to differing vehicle interfaces such as suitport and airlock, adjust to varying vehicle pressure schedules, tolerate lower quality working fluids, and adapt to differing suit architectures as dictated by a range of mission architectures, the next generation space suit requires more adaptability and robustness over that of the current Shuttle/ISS Extra-vehicular Mobility Unit (EMU). While some features have been added to facilitate interfaces to differing vehicle and suit architectures, the key performance gains have been made via incorporation of new technologies such as the variable pressure regulators, Rapid Cycle Amine swing-bed, and Suit Water Membrane Evaporator. This paper performs a comparison between the Shuttle/ISS EMU PLSS schematic and the Advanced EMU PLSS schematic complete with a discussion for each difference.
Author
EXTRAVEHICULAR MOBILITY UNITS; LIFE SUPPORT SYSTEMS
20110023483 Princeton Univ., NJ United States
Tire containing thermally exfoliated graphite oxide
Prud'homme, Robert K., Inventor; Aksay, Ilhan A., Inventor; November 1, 2011; In English
Contract(s)/Grant(s): NCC1-02037
Patent Info.: August 19, 2008US-Patent-8,047,248; US-Patent-Appl-SN-12/194,037
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023483
A tire, tire lining or inner tube, containing a polymer composite, made of at least one rubber and/or at least one elastomer and a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m/g.
Official Gazette of the U.S. Patent and Trademark Office
TIRES; RUBBER; GRAPHITE
20110023484 NASA, Washington, DC United States
Ram booster
Brand, Vance D., Inventor; Morgan, Walter Ray, Inventor; November 1, 2011; In English
Patent Info.: March 11, 2008US-Patent-8,047,472; US-Patent-Appl-SN-12/045,970
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023484
The present invention is a space launch system and method to propel a payload bearing craft into earth orbit. The invention has two, or preferably, three stages. The upper stage has rocket engines capable of carrying a payload to orbit and provides the capability of releasably attaching to the lower, or preferably, middle stage. Similar to the lower stage, the middle stage is a reusable booster stage that employs all air breathing engines, is recoverable, and can be turned-around in a short time between missions.
Official Gazette of the U.S. Patent and Trademark Office
AIR BREATHING ENGINES; BOOSTER ROCKET ENGINES; SPACECRAFT LAUNCHING; ROCKET ENGINES
20110023485 California Inst. of Tech., Pasadena, CA United States
Atomic ion clock with two ion traps, and method to transfer ions
Prestage, John D., Inventor; Chung, Sang K., Inventor; November 15, 2011; In English
Patent Info.: August 29, 2008US-Patent-8,058,936; US-Patent-Appl-SN-12/201,848
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023485
An atomic ion clock with a first ion trap and a second ion trap, where the second ion trap is of higher order than the first ion trap. In one embodiment, ions may be shuttled back and forth from one ion trap to the other by application of voltage ramps to the electrodes in the ion traps, where microwave interrogation takes place when the ions are in the second ion trap, and fluorescence is induced and measured when the ions are in the first ion trap. In one embodiment, the RF voltages applied to the second ion trap to contain the ions are at a higher frequency than that applied to the first ion trap. Other embodiments are described and claimed.
Official Gazette of the U.S. Patent and Trademark Office
ATOMIC CLOCKS; ELECTRIC POTENTIAL; RADIO FREQUENCIES; MICROWAVES; ELECTRODES
20110023486 NASA Johnson Space Center, Houston, TX, United States
Computational Electromagnetics (CEM) Laboratory: Simulation Planning Guide
Khayat, Michael A.; [2011]; In English; Original contains color illustrations
Report No.(s): JSC-CN-25197; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023486
The simulation process, milestones and inputs are unknowns to first-time users of the CEM Laboratory. The Simulation Planning Guide aids in establishing expectations for both NASA and non-NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware/software developers. It is intended to assist their engineering personnel in simulation planning and execution. Material covered includes a roadmap of the simulation process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, facility interfaces, and inputs necessary to define scope, cost, and schedule are included as an appendix to the guide.
Author
COMPUTATIONAL ELECTROMAGNETICS; SIMULATION; SCHEDULES; COMPUTER PROGRAMS; PERSONNEL; SPACE FLIGHT
20110023488 NASA Goddard Space Flight Center, Greenbelt, MD, United States
An Attempt to Derive the epsilon Equation from a Two-Point Closure
Canuto, V. M.; Cheng, Y.; Howard, A. M.; Journal of Atmospheric Sciences; May 2010; vol. Volume 65; issue Iss. 5; pp. 1678-168; In English; Original contains black and white illustrations
Report No.(s): GSFC.JA.5408.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1175/2009JAS3290.1
The goal of this paper is to derive the equation for the turbulence dissipation rate epsilon for a shear-driven flow. In 1961, Davydov used a one-point closure model to derive the epsilon equation from first principles but the final result contained undetermined terms and thus lacked predictive power. Both in 1987 and in 2001, attempts were made to derive the epsilon equation from first principles using a two-point closure, but their methods relied on a phenomenological assumption. The standard practice has thus been to employ a heuristic form of the equation that contains three empirical ingredients: two constants, c(sub 1 epsilon), and c(sub 2 epsilon), and a diffusion term D(sub epsilon) In this work, a two-point closure is employed, yielding the following results: 1) the empirical constants get replaced by c(sub 1), c(sub 2), which are now functions of Kappa and epsilon; 2) c(sub 1) and c(sub 2) are not independent because a general relation between the two that are valid for any Kappa and epsilon are derived; 3) c(sub 1), c(sub 2) become constant with values close to the empirical values c(sub 1 epsilon), c(sub epsilon 2), (i.e., homogenous flows); and 4) the empirical form of the diffusion term D(sub epsilon) is no longer needed because it gets substituted by the Kappa-epsilon dependence of c(sub 1), c(sub 2), which plays the role of the diffusion, together with the diffusion of the turbulent kinetic energy D(sub Kappa), which now enters the new equation (i.e., inhomogeneous flows). Thus, the three empirical ingredients c(sub 1 epsilon), c(sub epsilon 2), D (sub epsilon)are replaced by a single function c(sub 1)(Kappa, epsilon ) or c(sub 2)(Kappa, epsilon ), plus a D(sub Kappa)term. Three tests of the new equation for epsilon are presented: one concerning channel flow and two concerning the shear-driven planetary boundary layer (PBL).
Author
CLOSURE LAW; ATMOSPHERIC TURBULENCE; TURBULENT DIFFUSION; ATMOSPHERIC DIFFUSION; SHEAR FLOW
20110023489 General Motors Corp., Detroit, MI United States
Method and apparatus for electromagnetically braking a motor
Davis, Donald R., Inventor; Radford, Nicolaus A, Inventor; Permenter, Frank Noble, Inventor; Parsons, Adam H, Inventor; Mehling, Joshua S, Inventor; November 29, 2011; In English
Patent Info.: May 29, 2009US-Patent-8,067,909; US-Patent-Appl-SN-12/474,430
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023489
An electromagnetic braking system and method is provided for selectively braking a motor using an electromagnetic brake having an electromagnet, a permanent magnet, a rotor assembly, and a brake pad. The brake assembly applies when the electromagnet is de-energized and releases when the electromagnet is energized. When applied the permanent magnet moves the brake pad into frictional engagement with a housing, and when released the electromagnet cancels the flux of the permanent magnet to allow a leaf spring to move the brake pad away from the housing. A controller has a DC/DC converter for converting a main bus voltage to a lower braking voltage based on certain parameters. The converter utilizes pulse-width modulation (PWM) to regulate the braking voltage. A calibrated gap is defined between the brake pad and permanent magnet when the brake assembly is released, and may be dynamically modified via the controller.
Official Gazette of the U.S. Patent and Trademark Office
ELECTROMAGNETS; BRAKING; CALIBRATING; VOLTAGE CONVERTERS (DC TO DC); PULSE DURATION MODULATION; FRICTION FACTOR; PERMANENT MAGNETS; ELECTRIC POTENTIAL
20110023490 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Iron Abundance in the Prototype PG 1159 Star, GW Vir Pulsator PG 1159-035, and Related Objects
Werner, K.; Rauch, T.; Kruk, J. W.; Kurucz, R. L.; Astronomy and Astrophysics; July 4, 2011; vol. Volume 531; issue No. 6; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NAS5-26555; NAS5--32985NNX09AF08G; DLR 05 OR 0806
Report No.(s): GSFC.JA.5432.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1051/0004-6361/201116992
We performed an iron abundance determination of the hot, hydrogen deficient post-AGB star PG 1159-035. which is the prototype of the PG 1159 spectral class and the GW Vir pulsators, and of two related objects (PG 1520+525, PG 1144+005), based on the first detection of Fe VIII lines in stellar photospheres. In another PG 1159 star. PG 1424+535. we detect Fe VII lines. In all four stars, each within T(sub eff) = 110,000-150,000 K, we find a solar iron abundance. This result agrees with our recent abundance analysis of the hottest PG 1159 stars (T(sub eff) = 150,000-200,000 K) that exhibit Fe x lines. On the whole, we find that the PG 1159 stars are not significantly iron deficient, in contrast to previous notions.
Author
ASYMPTOTIC GIANT BRANCH STARS; ABUNDANCE; IRON; VARIABLE STARS; METALLICITY
20110023491 CFD Research Corp., Huntsville, AL United States
Apparatus and method for gelling liquefied gasses
Elliott, Adam, Inventor; DiSalvo, Roberto, Inventor; Shepherd, Phillip, Inventor; Kosier, Ryan, Inventor; November 1, 2011; In English
Contract(s)/Grant(s): NNM05AA56C
Patent Info.: September 2, 2010US-Patent-8,047,703; US-Patent-Appl-SN-12/874,242
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023491
A method and apparatus for gelling liquid propane and other liquefied gasses includes a temperature controlled churn mixer, vacuum pump, liquefied gas transfer tank, and means for measuring amount of material entering the mixer. The apparatus and method are particularly useful for the production of high quality rocket fuels and propellants.
Official Gazette of the U.S. Patent and Trademark Office
GELS; LIQUEFIED GASES; MIXERS; PROPANE; GELATION
20110023492 NASA Johnson Space Center, Houston, TX, United States
Eagleworks Laboratories: Advanced Propulsion Physics Research
White, Harold; March, Paul; Williams, Nehemiah; ONeill, William; December 05, 2011; In English; JANNAF Joint Propulsion Meeting, 5-9 Dec. 2011, Huntsville, AL, United States; Original contains color illustrations
Report No.(s): JSC-CN-25207; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023492
NASA/JSC is implementing an advanced propulsion physics laboratory, informally known as "Eagleworks", to pursue propulsion technologies necessary to enable human exploration of the solar system over the next 50 years, and enabling interstellar spaceflight by the end of the century. This work directly supports the "Breakthrough Propulsion" objectives detailed in the NASA OCT TA02 In-space Propulsion Roadmap, and aligns with the #10 Top Technical Challenge identified in the report. Since the work being pursued by this laboratory is applied scientific research in the areas of the quantum vacuum, gravitation, nature of space-time, and other fundamental physical phenomenon, high fidelity testing facilities are needed. The lab will first implement a low-thrust torsion pendulum (<1 uN), and commission the facility with an existing Quantum Vacuum Plasma Thruster. To date, the QVPT line of research has produced data suggesting very high specific impulse coupled with high specific force. If the physics and engineering models can be explored and understood in the lab to allow scaling to power levels pertinent for human spaceflight, 400kW SEP human missions to Mars may become a possibility, and at power levels of 2MW, 1-year transit to Neptune may also be possible. Additionally, the lab is implementing a warp field interferometer that will be able to measure spacetime disturbances down to 150nm. Recent work published by White [1] [2] [3] suggests that it may be possible to engineer spacetime creating conditions similar to what drives the expansion of the cosmos. Although the expected magnitude of the effect would be tiny, it may be a "Chicago pile" moment for this area of physics.
Author
SPECIFIC IMPULSE; PROPULSION; GRAVITATION; SPACE-TIME FUNCTIONS; VACUUM; SPACE FLIGHT; PLASMAS (PHYSICS); HIGH IMPULSE
20110023493 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Measurement of Separate Cosmic-Ray Electron and Positron Spectra with the Fermi Large Area Telescope
Ackermann, M.; Ajello, M.; Allafort, A.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Bonamente, E.; Brogland, A. W.; Bouvier, A.; Bregeon, J.; Brigida, M.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Ferrara, E. C.; Harding, A. K.; McEnery, J. E.; et al.; [2011]; In English; Original contains black and white illustrations
Report No.(s): GSFC.JA.5422.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023493
We measured separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Because the instrument does not have an onboard magnet, we distinguish the two species by exploiting the Earth's shadow, which is offset in opposite directions for opposite charges due to the Earth's magnetic field. We estimate and subtract the cosmic-ray proton background using two different methods that produce consistent results. We report the electron-only spectrum, the positron-only spectrum, and the positron fraction between 20 GeV and 200 GeV, We confirm that the fraction rises with energy in the 20-100 GeV range and determine for the first time that it continues to rise between 100 and 200 GeV,
Author
ELECTRON SPECTROSCOPY; GEOMAGNETISM; COSMIC RAYS; POSITRONS; ELECTRONS; PROTONS
20110023494 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Fermi Large Area Telescope Observations of the Supernova Remnant GS.7-0.1
Ajello, M.; Allafort, A.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Bonamente, E.; Borgland, A. W.; Bregeon, J.; Brigida, M.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Ferrara, E. C.; Harding, A. K.; Hays, E.; Moiseev, A. A.; Troja, E.; et al.; [2011]; In English; Original contains black and white illustrations
Report No.(s): GSFC.JA.5424.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023494
We present a detailed analysis of the GeV gamma-ray emission toward the supernova remnant (SNR) G8.7-0.1 with the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope. An investigation of the relationship among G8.7-0.l and the TeV unidentified source HESS J1804-216 provides us with an important clue on diffusion process of cosmic rays if particle acceleration operates in the SNR. The GeV gamma-ray emission is extended with most of the emission in positional coincidence with the SNR G8.7-0.l and a lesser part located outside the western boundary of G8.7-0.l. The region of the gamma-ray emission overlaps spatially-connected molecular clouds, implying a physical connection for the gamma-ray structure. The total gamma-ray spectrum measured with LAT from 200 MeV-100 GeV can be described by a broken power-law function with a break of 2.4 +/- 0.6 (stat) +/- 1.2 (sys) GeV, and photon indices of 2.10 +/- 0.06 (stat) +/- 0.10 (sys) below the break and 2.70 +/- 0.12 (stat) +/- 0.l4 (sys) above the break. Given the spatial association among the gamma rays, the radio emission of G8.7-0.1, and the molecular clouds, the decay of 1IoS produced by particles accelerated in the SNR and hitting the molecular clouds naturally explains the GeV gamma-ray spectrum. We also find that the GeV morphology is not well represented by the TeV emission from HESS J1804-216 and that the spectrum in the GeV band is not consistent with the extrapolation of the TeV gamma-ray spectrum. The spectral index of the TeV emission is consistent with the particle spectral index predicted by a theory that assumes energy-dependent diffusion of particles accelerated in an SNR. We discuss the possibility that the TeV spectrum originates from the interaction of particles accelerated in G8.7-0.1 with molecular clouds, and we constrain the diffusion coefficient of the particles.
Author
COSMIC RAYS; GAMMA RAY SPECTRA; SPACEBORNE TELESCOPES; PARTICLE DIFFUSION; SUPERNOVA REMNANTS; PARTICLE ACCELERATION; PARTICLE ENERGY; RADIO EMISSION
20110023495 Princeton Univ., NJ United States
Packaging material and flexible medical tubing containing thermally exfoliated graphite oxide
Prud'homme, Robert K., Inventor; Aksay, Ilhan A., Inventor; November 22, 2011; In English
Contract(s)/Grant(s): NCC1-02037
Patent Info.: August 19, 2008US-Patent-8,063,134; US-Patent-Appl-SN-12/194,062
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023495
A packaging material or flexible medical tubing containing a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 m.sup.2/g to 2600 m.sup.2/g.
Official Gazette of the U.S. Patent and Trademark Office
GRAPHITE; OXIDES; PACKAGING; PIPES (TUBES); NANOPARTICLES; NANOTECHNOLOGY
20110023497 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Advanced Technology Large Aperture Space Telescope (ATLAST): Science Drivers and Technology Developments
Postman, Marc; Brown, Tom; Sembach, Kenneth; Giavalisco, Mauro; Traub, Wesley; Stapelfeldt, Karl; Calzetti, Daniela; Oegerle, William; Rich, R. Michael; Stahl, H. Phillip; Tumlinson, Jason; Mountain, Matt; Soummer, Remi; Hyde, Tupper; [2011]; In English; Original contains color illustrations
Report No.(s): GSFC.JA.5426.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023497
The Advanced Technology Large-Aperture Space Telescope (ATLAST) is a concept for an 8-meter to 16-meter UVOIR space observatory for launch in the 2025-2030 era. ATLAST will allow astronomers to answer fundamental questions at the forefront of modern astrophysics, including "Is there life elsewhere in the Galaxy?" We present a range of science drivers and the resulting performance requirements for ATLAST (8 to 16 milliarcsecond angular resolution, diffraction limited imaging at 0.5 m wavelength, minimum collecting area of 45 square meters, high sensitivity to light wavelengths from 0.1 m to 2.4 m, high stability in wavefront sensing and control). We also discuss the priorities for technology development needed to enable the construction of ATLAST for a cost that is comparable to current generation observatory-class space missions. Keywords: Advanced Technology Large-Aperture Space Telescope (ATLAST); ultraviolet/optical space telescopes; astrophysics; astrobiology; technology development.
Author
SPACEBORNE TELESCOPES; APERTURES; IMAGING TECHNIQUES; SPACECRAFT LAUNCHING; ULTRAVIOLET TELESCOPES; ASTROPHYSICS; DIFFRACTION
20110023498 Massachusetts Inst. of Tech., Cambridge, MA, United States
Suzaku Observations of 4U 1957+11: Potentially the Most Rapidly Spinning Black Hole in (the Halo of) the Galaxy
Nowak, Michael A.; Wilms, Joern; Pottschmidt, Katja; Schulz, Norbert; Maitra, Dipankar; Miller, Jon; [2011]; In English; Original contains black and white illustrations
Contract(s)/Grant(s): ITN 215212NNG06EO90A; NNX10AR94G; SV3-73016; DLR 50OR0701; DLR 50OR1005
Report No.(s): GSFC.JA.5436.2011; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023498
We present three Suzaku observations of the black hole candidate 4U 1957+11 (V 1408 Aql) - a source that exhibits some of. the simplest and cleanest examples of soft, disk-dominated spectra. 4U 1957+ II also presents among the. highest peak temperatures found from disk-dominated spectra. Such temperatures may be associated with rapid black hole spin. The 4U 1957+11 spectra also require a very low normalization, which can be explained by a combination of small inner disk radius and a large distance (> 10 kpc) which places 4U 1957+ 11 well into the Galactic halo. We perform Joint fits to the Suzaku spectra with both relativistic and Comptonized disk models. Assuming a low mass black hole and the nearest distance (3 Stellar Mass, 10 kpc), the dimensionless spin parameter a* = Jc/GM(sup 2)> or approx. 0.9. Higher masses and farther distances yield a* approx. = 1. Similar conclusions are reached with Comptonization models; they imply a combination of small inner disk radii (or, equivalently, rapid spin) and large distance. Low spin cannot be recovered unless 4U 1957+11 is a low mass black hole that is at the unusually large distance of > or approx.40 kpc. We speculate whether the suggested maximal spin is related to how the system came to reside in the halo.
Author
BLACK HOLES (ASTRONOMY); STELLAR MASS; COMPTON EFFECT; HALOS; BINARY STARS; X RAY BINARIES
20110023499 NASA Johnson Space Center, Houston, TX, United States
Structural Design Requirements and Factors of Safety for Spaceflight Hardware: For Human Spaceflight
Bernstein, Karen S.; Kujala, Rod; Fogt, Vince; Romine, Paul; October 2011; In English
Report No.(s): JSC 65828 Rev. A; JSC-CN-25316; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023499
This document establishes the structural requirements for human-rated spaceflight hardware including launch vehicles, spacecraft and payloads. These requirements are applicable to Government Furnished Equipment activities as well as all related contractor, subcontractor and commercial efforts. These requirements are not imposed on systems other than human-rated spacecraft, such as ground test articles, but may be tailored for use in specific cases where it is prudent to do so such as for personnel safety or when assets are at risk. The requirements in this document are focused on design rather than verification. Implementation of the requirements is expected to be described in a Structural Verification Plan (SVP), which should describe the verification of each structural item for the applicable requirements. The SVP may also document unique verifications that meet or exceed these requirements with NASA Technical Authority approval.
Author
STRUCTURAL DESIGN; SPACE FLIGHT; LAUNCH VEHICLES; GROUND TESTS; PAYLOADS
20110023500 Princeton Univ., NJ United States
Emulsifier containing thermally exfoliated graphite oxide
Prud'Homme, Robert K., Inventor; Aksay, Ilhan A., Inventor; November 1, 2011; In English
Contract(s)/Grant(s): NCC1-02037
Patent Info.: August 19, 2008US-Patent-8,048,931; US-Patent-Appl-SN-12/194,054
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023500
An emulsifier containing a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 m.sup.2/g to 2600 m.sup.2/g.
Official Gazette of the U.S. Patent and Trademark Office
GRAPHITE; OXIDES; NANOPARTICLES; EMULSIONS; NANOCOMPOSITES; NANOTECHNOLOGY
20110023501 NASA, Washington, DC United States
Self-healing polymers
Klein, Daniel J., Inventor; November 22, 2011; In English
Contract(s)/Grant(s): NCC-102043
Patent Info.: January 9, 2009US-Patent-8,063,171; US-Patent-Appl-SN-12/319,710
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023501
A three dimensional structure fabricated from a self-healing polymeric material, comprising poly(ester amides) obtained from ethylene glycol, azelaic acid and 1,1-aminoundecanoic acid, wherein polymeric material has a melt index above 2.5 g/10 min. as determined by ASTM D1238 at 190.degree. C. and 2.16kg, impact resistance and ductility sufficient to resist cracking and brittle fracture upon impact by a 9 mm bullet fired at a temperature of about 29.degree. C. at subsonic speed in a range from about 800 feet/sec to about 1000 feet/sec. It has been determined that the important factors necessary for self-healing behavior of polymers include sufficient impact strength, control of the degree of crystallinity, low melting point and the ability to instantly melt at impacted area.
Official Gazette of the U.S. Patent and Trademark Office
HEALING; POLYMERS; ETHYLENE COMPOUNDS; FABRICATION; GLYCOLS; IMPACT RESISTANCE; MELTING POINTS; CRYSTALLINITY
20110023502 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Mixed Layer Sub-Mesoscale Parameterization - Part 1: Derivation and Assessment
Canuto, V. M.; Dubovikov, M. S.; Ocean Science; January 2010; vol. Volume 6; pp. 679-69; In English; Original contains color illustrations
Report No.(s): GSFC.JA.5407.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023502
http://dx.doi.org/10.5194/os-6-679-2010
Several studies have shown that sub-mesoscales (SM 1km horizontal scale) play an important role in mixed layer dynamics. In particular, high resolution simulations have shown that in the case of strong down-front wind, the re-stratification induced by the SM is of the same order of the de-stratification induced by small scale turbulence, as well as of that induced by the Ekman velocity. These studies have further concluded that it has become necessary to include SM in ocean global circulation models (OGCMs), especially those used in climate studies. The goal of our work is to derive and assess an analytic parameterization of the vertical tracer flux under baroclinic instabilities and wind of arbitrary directions and strength. To achieve this goal, we have divided the problem into two parts: first, in this work we derive and assess a parameterization of the SM vertical flux of an arbitrary tracer for ocean codes that resolve mesoscales, M, but not sub-mesoscales, SM. In Part 2, presented elsewhere, we have used the results of this work to derive a parameterization of SM fluxes for ocean codes that do not resolve either M or SM. To carry out the first part of our work, we solve the SM dynamic equations including the non-linear terms for which we employ a closure developed and assessed in previous work. We present a detailed analysis for down-front and up-front winds with the following results: (a) down-front wind (blowing in the direction of the surface geostrophic velocity) is the most favorable condition for generating vigorous SM eddies; the de-stratifying effect of the mean flow and re-stratifying effect of SM almost cancel each other out,
Author
ATMOSPHERIC MODELS; MESOSCALE PHENOMENA; OCEAN CURRENTS; OCEAN MODELS; TURBULENCE; WIND DIRECTION
20110023503 Vanderbilt Univ., Nashville, TN United States
System and method for image mapping and visual attention
Peters, II, Richard A., Inventor; November 15, 2011; In English
Contract(s)/Grant(s): NNJ04HI19G
Patent Info.: November 16, 2010US-Patent-8,060,272; US-Patent-Appl-SN-12/947,629
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023503
A method is described for mapping dense sensory data to a Sensory Ego Sphere (SES). Methods are also described for finding and ranking areas of interest in the images that form a complete visual scene on an SES. Further, attentional processing of image data is best done by performing attentional processing on individual full-size images from the image sequence, mapping each attentional location to the nearest node, and then summing all attentional locations at each node.
Official Gazette of the U.S. Patent and Trademark Office
IMAGE PROCESSING; RANKING; POSITION (LOCATION); SPHERES
20110023504 NASA Johnson Space Center, Houston, TX, United States
Commercial Crew Development Environmental Control and Life Support System Status: 2011-2012
Williams, David E.; [2011]; In English; 42nd International Conference on Environmental Systems, 15019 Jul. 2012, San Diego, CA, United States
Contract(s)/Grant(s): WBS 086916.01.01.01.02.01
Report No.(s): JSC-CN-25281; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023504
The National Aeronautics and Space Administration (NASA) Commercial Crew Development (CCDev) - 2 Program is managed within the new Commercial Crew Program Office (CCPO) to help develop a commercial crew transportation system to low earth orbit (LEO). It is intended to foster entrepreneurial activities with a few selected companies. The entrepreneurial activities were encouraged with these few selected companies by NASA providing only part of the total funding to complete specific tasks that were jointly agreed to by NASA and the company. These joint agreements were documented in a Space Act Agreement (SAA) that was signed jointly by NASA and the selected company. This paper will provide an overview of the CCDev - 2 Program and also it will discuss in a high level the Active Thermal Control System (ATCS) / Environmental Control and Life Support (ECLS) System tasks that were performed under CCDev - 2 from the start of CCDev - 2 to March 2012. It will also discuss the extension of the CCDev - 2 Program being proposed for the near future. 1
Author
LIFE SUPPORT SYSTEMS; SPACECREWS; ENVIRONMENTAL CONTROL; ACTIVE CONTROL; TEMPERATURE CONTROL; LOW EARTH ORBITS
20110023505 NASA Johnson Space Center, Houston, TX, United States
Near-Earth Objects: Targets for Future Human Exploration, Solar System Science, Resource Utilization, and Planetary Defense
Abell, Paul A.; December 05, 2011; In English; SEMS - Systems Engineering Mini Symposium, 5-7 Dec. 2011, Bremen, Germany
Report No.(s): JSC-CN-25272; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023505
U.S. President Obama stated on April 15, 2010 that the next goal for human spaceflight will be to send human beings to a near-Earth asteroid by 2025. Given this direction from the White House, NASA has been involved in studying various strategies for near-Earth object (NEO) exploration in order to follow U.S. Space Exploration Policy. This mission would be the first human expedition to an interplanetary body beyond the Earth-Moon system and would prove useful for testing technologies required for human missions to Mars and other Solar System destinations. Missions to NEOs would undoubtedly provide a great deal of technical and engineering data on spacecraft operations for future human space exploration while conducting in-depth scientific investigations of these primitive objects. In addition, the resulting scientific investigations would refine designs for future extraterrestrial resource extraction and utilization, and assist in the development of hazard mitigation techniques for planetary defense. This presentation will discuss some of the physical characteristics of NEOs and review some of the current plans for NEO research and exploration from both a human and robotic mission perspective.
Author
SPACE EXPLORATION; EXTRATERRESTRIAL RESOURCES; NEAR EARTH OBJECTS; MARS MISSIONS; SOLAR SYSTEM; EARTH-MOON SYSTEM; ASTEROIDS
20110023506 NASA Johnson Space Center, Houston, TX, United States
Shuttle/ISS EMU Failure History and the Impact on Advanced EMU PLSS Design
Campbell, Colin; [2011]; In English; 42nd International Conference on Environmental Systems, 15-19 Jul. 2012, San Diego, CA, United States
Contract(s)/Grant(s): WBS 780896.04.10.04.01.03.10
Report No.(s): JSC-CN-25114; No Copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023506
As the Shuttle/ISS EMU Program exceeds 30 years in duration and is still successfully supporting the needs of the International Space Station (ISS), a critical benefit of such a long running program with thorough documentation of system and component failures is the ability to study and learn from those failures when considering the design of the next generation space suit. Study of the subject failure history leads to changes in the Advanced EMU Portable Life Support System (PLSS) schematic, selected component technologies, as well as the planned manner of ground testing. This paper reviews the Shuttle/ISS EMU failure history and discusses the implications to the AEMU PLSS.
Author
EXTRAVEHICULAR MOBILITY UNITS; FAILURE; LIFE SUPPORT SYSTEMS; FAILURE ANALYSIS
20110023507 Boeing Information, Space and Defense Systems, Houston, TX, United States
Report on ISS Oxygen Production, Resupply, and Partial Pressure Management
Schaezler, Ryan; Ghariani, Ahmed; Leonard, Daniel; Lehman, Daniel; [2011]; In English; 42nd International Conference of Environmental Systems, 15-19 Jul. 2012, San Diego, CA, United States
Report No.(s): JSC-CN-25345; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023507
The majority of oxygen used on International Space Station (ISS) is for metabolic support and denitrogenation procedures prior to Extra-Vehicular Activities. Oxygen is supplied by various visiting vehicles such as the Progress and Shuttle in addition to oxygen production capability on both the United States On-Orbit Segment (USOS) and Russian Segment (RS). To maintain a habitable atmosphere the oxygen partial pressure is controlled between upper and lower bounds. The full range of the allowable oxygen partial pressure along with the increased ISS cabin volume is utilized as a buffer allowing days to pass between oxygen production or direct addition of oxygen to the atmosphere from reserves. This paper summarizes amount of oxygen supplied and produced from all of the sources and describes past experience of managing oxygen partial pressure along with the range of management options available to the ISS.
Author
OXYGEN PRODUCTION; PARTIAL PRESSURE; DENITROGENATION; HABITABILITY; GAS PRESSURE; INTERNATIONAL SPACE STATION; ATMOSPHERIC PRESSURE
20110023508 NASA, Washington, DC United States
Advanced high performance vertical hybrid synthetic jet actuator
Xu, Tian-Bing, Inventor; Jiang, Xiaoning, Inventor; Su, Ji, Inventor; November 8, 2011; In English
Patent Info.: February 26, 2009US-Patent-8,052,069; US-Patent-Appl-SN-12/393,238
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023508
The present invention comprises a high performance, vertical, zero-net mass-flux, synthetic jet actuator for active control of viscous, separated flow on subsonic and supersonic vehicles. The present invention is a vertical piezoelectric hybrid zero-net mass-flux actuator, in which all the walls of the chamber are electrically controlled synergistically to reduce or enlarge the volume of the synthetic jet actuator chamber in three dimensions simultaneously and to reduce or enlarge the diameter of orifice of the synthetic jet actuator simultaneously with the reduction or enlargement of the volume of the chamber. The jet velocity and mass flow rate for the present invention will be several times higher than conventional piezoelectric synthetic jet actuators.
Official Gazette of the U.S. Patent and Trademark Office
ACTIVE CONTROL; JET CONTROL; MASS FLOW RATE; PIEZOELECTRIC ACTUATORS; VISCOUS FLOW; JET FLOW; VARIABLE THRUST
20110023509 NASA, Washington, DC United States
Process for preparing polymer reinforced silica aerogels
Meador, Mary Ann B., Inventor; Capadona, Lynn A., Inventor; November 29, 2011; In English
Patent Info.: October 19, 2006US-Patent-8,067,478; US-Patent-Appl-SN-11/582,693
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023509
Process for preparing polymer-reinforced silica aerogels which comprises a one-pot reaction of at least one alkoxy silane in the presence of effective amounts of a polymer precursor to obtain a silica reaction product, the reaction product is gelled and subsequently subjected to conditions that promotes polymerization of the precursor and then supercritically dried to obtain the polymer-reinforced monolithic silica aerogels.
Official Gazette of the U.S. Patent and Trademark Office
AEROGELS; POLYMERIZATION; ALKYL COMPOUNDS; SILICON DIOXIDE; SILANES
20110023510 Boeing Co., Houston, TX, United States
International Space Station (ISS) Gas Logistics Planning in the Post Shuttle Era
Leonard, Daniel J.; Cook, Anthony J.; Lehman, Daniel A.; [2011]; In English; 42nd International Conference of Environmental Systems, 15-18 Jul. 2012, San Diego, CA, United States
Report No.(s): JSC-CN-25348; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023510
Over its life the International Space Station (ISS) has received gas (nitrogen, oxygen, and air) from various sources. Nitrogen and oxygen are used in the cabin to maintain total pressure and oxygen partial pressures within the cabin. Plumbed nitrogen is also required to support on-board experiments and medical equipment. Additionally, plumbed oxygen is required to support medical equipment as well as emergency masks and most importantly EVA support. Gas are supplied to ISS with various methods and vehicles. Vehicles like the Progress and ATV deliver nitrogen (both as a pure gas and as air) and oxygen via direct releases into the cabin. An additional source of nitrogen and oxygen is via tanks on the ISS Airlock. The Airlock nitrogen and oxygen tanks can deliver to various users via pressurized systems that run throughout the ISS except for the Russian segment. Metabolic oxygen is mainly supplied via cabin release from the Elektron and Oxygen Generator Assembly (OGA), which are water electrolyzers. As a backup system, oxygen candles (Solid Fuel Oxygen Generators-SFOGs) supply oxygen to the cabin as well. In the past, a major source of nitrogen and oxygen has come from the Shuttle via both direct delivery to the cabin as well as to recharge the ISS Airlock tanks. To replace the Shuttle capability to recharge the ISS Airlock tanks, a new system was developed called Nitrogen/Oxygen Recharge System (NORS). NIORS consists of high pressure (7000 psi) tanks which recharge the ISS Airlock tanks via a blowdown fill for both nitrogen and oxygen. NORS tanks can be brought up on most logistics vehicles such as the HTV, COTS, and ATV. A proper balance must be maintained to insure sufficient gas resources are available on-orbit so that all users have the required gases via the proper delivery method (cabin and/or plumbed).
Author
NITROGEN; OXYGEN; AIR LOCKS; PARTIAL PRESSURE; OXYGEN SUPPLY EQUIPMENT; EXTRAVEHICULAR ACTIVITY; MEDICAL EQUIPMENT; HIGH PRESSURE
20110023511 NASA, Washington, DC United States
Electrochemical and mechanical polishing and shaping method and system
Engelhaupt, Darell E., Inventor; Gubarev, Mikhail V., Inventor; Jones, William David, Inventor; Ramsey, Brian D., Inventor; Benson, Carl M., Inventor; November 8, 2011; In English
Patent Info.: December 14, 2007US-Patent-8,052,860; US-Patent-Appl-SN-11/957,051
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023511
A method and system are provided for the shaping and polishing of the surface of a material selected from the group consisting of electrically semi-conductive materials and conductive materials. An electrically non-conductive polishing lap incorporates a conductive electrode such that, when the polishing lap is placed on the material's surface, the electrode is placed in spaced-apart juxtaposition with respect to the material's surface. A liquid electrolyte is disposed between the material's surface and the electrode. The electrolyte has an electrochemical stability constant such that cathodic material deposition on the electrode is not supported when a current flows through the electrode, the electrolyte and the material. As the polishing lap and the material surface experience relative movement, current flows through the electrode based on (i) adherence to Faraday's Law, and (ii) a pre-processing profile of the surface and a desired post-processing profile of the surface.
Official Gazette of the U.S. Patent and Trademark Office
ELECTRICAL RESISTIVITY; ELECTROPOLISHING; ELECTRODES; SEMICONDUCTORS (MATERIALS); ELECTROLYTES
20110023512 NASA Goddard Space Flight Center, Greenbelt, MD, United States
New Analysis of Lunar Prospector Radio Tracking Data Brings the Nearside Gravity Field of the Moon with an Unprecedented Resolution
Han, Shin-Chan; Mazarico, Erwan; Rowlands, David; Lemoine, Frank; Goossens, Sander; Icarus; August 05, 2011; ISSN 0019-1035; vol. Voilume 215; issue Issue 2; pp. 455-45; In English; Original contains black and white illustrations
Report No.(s): GSFC.JA.5446.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1016/j.icarus.2011.07.020
A new analysis of the Doppler tracking data from the Lunar Prospector mission in 1999 revealed a number of previously-unseen gravity anomalies at spatial scales as small as 27 km over the nearside. The tracking data at low altitudes (50 km or below) were better analyzed to resolve the nearside features without dampening from a power law constraint, by partitioning the gravity parameters concentrated on either the nearside or farside. The resulting model presents gravity anomalies correlated with topography with a correlation coefficient of 0.7 or higher from degree 50 to 150, the widest bandwidth yet. The gravity-topography admittance of approx. 70 mGal/km is found from numerous craters of which diameters are 60 km or less. In addition, the new model produces orbits that fit to independent radio tracking data from the Lunar Reconnaissance Orbiter and Kaguya (SELENE) better than previous gravity models. This high-resolution model can be of immediate use to geophysical analysis of small craters. Our technique could be applied to an upcoming mission, the Gravity Recovery And Interior Laboratory and useful to extract short wavelength signals from the MESSENGER Doppler data.
Author
LUNAR PROSPECTOR; RADIO TRACKING; GRAVITATIONAL FIELDS; HIGH RESOLUTION; RECONNAISSANCE; CRATERS; DOPPLER RADAR; GEOPHYSICS
20110023513 NASA, Washington, DC United States
Carbon dioxide gas sensors and method of manufacturing and using same
Hunter, Gary W., Inventor; Xu, Jennifer C., Inventor; Liu, Chung Chiun, Inventor; Ward, Benjamin J., Inventor; November 8, 2011; In English
Patent Info.: May 25, 2007US-Patent-8,052,854; US-Patent-Appl-SN-11/754,255
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023513
A gas sensor includes a substrate and a pair of interdigitated metal electrodes selected from the group consisting of Pt, Pd, Au, Ir, Ag, Ru, Rh, In, and Os. The electrodes each include an upper surface. A first solid electrolyte resides between the interdigitated electrodes and partially engages the upper surfaces of the electrodes. The first solid electrolyte is selected from the group consisting of NASICON, LISICON, KSICON, and .beta.''-Alumina (beta prime-prime alumina in which when prepared as an electrolyte is complexed with a mobile ion selected from the group consisting of Na.sup.+, K.sup.+, Li.sup.+, Ag.sup.+, H.sup.+, Pb.sup.2+, Sr.sup.2+ or Ba.sup.2+). A second electrolyte partially engages the upper surfaces of the electrodes and engages the first solid electrolyte in at least one point. The second electrolyte is selected from the group of compounds consisting of Na.sup.+, K.sup.+, Li.sup.+, Ag.sup.+, H.sup.+, Pb.sup.2+, Sr.sup.2+ or Ba.sup.2+ ions or combinations thereof.
Official Gazette of the U.S. Patent and Trademark Office
CARBON DIOXIDE; GAS DETECTORS; SOLID ELECTROLYTES; ELECTRODES
20110023514 Princeton Univ., NJ United States
Electrospray painted article containing thermally exfoliated graphite oxide and method for their manufacture
Korkut, Sibel, Inventor; Prud'Homme, Robert K., Inventor; Aksay, Ilhan A., Inventor; November 8, 2011; In English
Contract(s)/Grant(s): NCC1-02037
Patent Info.: September 11, 2008US-Patent-8,053,508; US-Patent-Appl-SN-12/208,692
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023514
A painted polymer part containing a conductive polymer composition containing at least one polymer and a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m/g, wherein the painted polymer part has been electrospray painted.
Official Gazette of the U.S. Patent and Trademark Office
GRAPHITE; OXIDES; COATINGS; CONDUCTING POLYMERS
20110023515 Princeton Univ., NJ United States
Wire coating containing thermally exfoliated graphite oxide
Prud'homme, Robert K., Inventor; Aksay, Ilhan A., Inventor; Adamson, Douglas, Inventor; Abdala, Ahmed, Inventor; November 1, 2011; In English
Contract(s)/Grant(s): NCC1-02037
Patent Info.: August 19, 2008US-Patent-8,048,950; US-Patent-Appl-SN-12/194,007
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023515
A wire coating containing a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m.sup.2/g.
Official Gazette of the U.S. Patent and Trademark Office
WIRE; COATING; GRAPHITE; OXIDES
20110023516 NASA Johnson Space Center, Houston, TX, United States
ISS Has an Attitude! Determining ISS Attitude at the ISS Window Observational Research Facility (WORF) Using Landmarks
Runco, Susan K.; Pickard,Henry; Kowtha, Vijayanand; Jackson, Dan; December 02, 2011; In English; NASA Education Stakeholders'Summit: NASA One Stop Shopping Initiative (OSSI) LaunchPad, 2 Dec. 2011, Chantilly, VA, United States; Original contains color illustrations
Report No.(s): JSC-CN-25352; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023516
Universities and secondary schools can help solve a real issue for remote sensing from the ISS WORF through hands-on engineering and activities. Remote sensing technology is providing scientists with higher resolution, higher sensitivity sensors. Where is it pointing? - To take full advantage of these improved sensors, space platforms must provide commensurate improvements in attitude determination
Derived from text
LANDMARKS; REMOTE SENSING; HORIZONTAL ORIENTATION; VERTICAL ORIENTATION; SATELLITE ORIENTATION; INTERNATIONAL SPACE STATION; ATTITUDE (INCLINATION)
20110023517 Cleveland State Univ., Cleveland, OH United States
Controllers, observers, and applications thereof
Gao, Zhiqiang, Inventor; Miklosovic, Robert, Inventor; Radke, Aaron, Inventor; Zhou, Wankun, Inventor; Zheng, Qing, Inventor; November 15, 2011; In English
Contract(s)/Grant(s): NGT3-52387.
Patent Info.: September 18, 2006US-Patent-8,060,340; US-Patent-Appl-SN-12/067,141
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023517
Controller scaling and parameterization are described. Techniques that can be improved by employing the scaling and parameterization include, but are not limited to, controller design, tuning and optimization. The scaling and parameterization methods described here apply to transfer function based controllers, including PID controllers. The parameterization methods also apply to state feedback and state observer based controllers, as well as linear active disturbance rejection (ADRC) controllers. Parameterization simplifies the use of ADRC. A discrete extended state observer (DESO) and a generalized extended state observer (GESO) are described. They improve the performance of the ESO and therefore ADRC. A tracking control algorithm is also described that improves the performance of the ADRC controller. A general algorithm is described for applying ADRC to multi-input multi-output systems. Several specific applications of the control systems and processes are disclosed.
Official Gazette of the U.S. Patent and Trademark Office
DESIGN OPTIMIZATION; CONTROLLERS; TRANSFER FUNCTIONS; FEEDBACK; PARAMETERIZATION
20110023518 NASA, Washington, DC United States
Connecting node and method for constructing a connecting node
Johnson, Christopher J., Inventor; Raboin, Jasen L., Inventor; Spexarth, Gary R., Inventor; November 1, 2011; In English
Patent Info.: September 29, 2008US-Patent-8,047,473; US-Patent-Appl-SN-12/240,537
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023518
A connecting node comprises a polyhedral structure comprising a plurality of panels joined together at its side edges to form a spherical approximation, wherein at least one of the plurality of panels comprises a faceted surface being constructed with a passage for integrating with one of a plurality of elements comprising a docking port, a hatch, and a window that is attached to the connecting node. A method for manufacturing a connecting node comprises the steps of providing a plurality of panels, connecting the plurality of panels to form a spherical approximation, wherein each edge of each panel of the plurality is joined to another edge of another panel, and constructing at least one of the plurality of panels to include a passage for integrating at least one of a plurality of elements that may be attached to the connecting node.
Official Gazette of the U.S. Patent and Trademark Office
CONNECTORS; DOCKING; PANELS
20110023519 NASA, Washington, DC United States
Method of fabricating a whispering gallery mode resonator
Savchenkov, Anatoliy A., Inventor; Matkso, Andrey B., Inventor; Iltchenko, Vladimir S., Inventor; Maleki, Lute, Inventor; November 15, 2011; In English
Patent Info.: May 13, 2008US-Patent-8,057,283; US-Patent-Appl-SN-12/119,989
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023519
A method of fabricating a whispering gallery mode resonator (WGMR) is provided. The WGMR can be fabricated from a particular material, annealed, and then polished. The WGMR can be repeatedly annealed and then polished. The repeated polishing of the WGMR can be carried out using an abrasive slurry. The abrasive slurry can have a predetermined, constant grain size. Each subsequent polishing of the WGMR can use an abrasive slurry having a grain size that is smaller than the grain size of the abrasive slurry of the previous polishing iteration.
Official Gazette of the U.S. Patent and Trademark Office
WHISPERING GALLERY MODES; RESONATORS; FABRICATION; POLISHING; GRAIN SIZE; ABRASIVES
20110023520 Orbital Technologies Corp., Madison, WI United States
Process to create simulated lunar agglutinate particles
Gustafson, Robert J., Inventor; Gustafson, Marty A., Inventor; White, Brant C., Inventor; November 29, 2011; In English
Contract(s)/Grant(s): NNM06AA76C
Patent Info.: January 22, 2008US-Patent-8,066,796; US-Patent-Appl-SN-12/017,681
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023520
A method of creating simulated agglutinate particles by applying a heat source sufficient to partially melt a raw material is provided. The raw material is preferably any lunar soil simulant, crushed mineral, mixture of crushed minerals, or similar material, and the heat source creates localized heating of the raw material.
Official Gazette of the U.S. Patent and Trademark Office
LUNAR SOIL; AGGLUTINATION; HEAT SOURCES; MINERALS; HEATING
20110023522 Case Western Reserve Univ., Cleveland, OH United States
Silicon carbide and other films and method of deposition
Mehregany, Mehran, Inventor; Zorman, Christian A., Inventor; Fu, Xiao-An, Inventor; Dunning, Jeremy, Inventor; November 1, 2011; In English
Contract(s)/Grant(s): NCA3-201
Patent Info.: August 26, 2009US-Patent-RE42,887; US-Patent-Appl-SN-12/548,363
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023522
A method of depositing a ceramic film, particularly a silicon carbide film, on a substrate is disclosed in which the residual stress, residual stress gradient, and resistivity are controlled. Also disclosed are substrates having a deposited film with these controlled properties and devices, particularly MEMS and NEMS devices, having substrates with films having these properties.
Official Gazette of the U.S. Patent and Trademark Office
SILICON CARBIDES; MICROELECTROMECHANICAL SYSTEMS; CONTROLLERS; ELECTRICAL RESISTIVITY; GRADIENTS
20110023523 University of Central Florida, Orlando, FL United States
Safe, in situ methodologies for the destruction of triacetone triperoxide and other explosive peroxides
Clausen, III, Christian, Inventor; Geiger, Cherie L., Inventor; Sigman, Michael, Inventor; Fidler, Rebecca, Inventor; November 22, 2011; In English
Contract(s)/Grant(s): NAG10-312.
Patent Info.: April 3, 2007US-Patent-8,062,442; US-Patent-Appl-SN-11/732,402
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023523
Triacetone triperoxide (TATP) and other explosives of the peroxide family are safely degraded in situ. Nano and micron size metal particles in an elemental state include pure iron and magnesium or iron and magnesium particles that are mechanically alloyed with palladium and nickel. The metal particles are used in both the elemental state and in emulsions that are made from water, a hydrophobic solvent, such as corn oil, and a food-grade nonionic surfactant. The neat metals and emulsified zero valent metals (EZVM) safely degrade TATP with the major degradation product being acetone. The EZVM system absorbs and dissolves the TATP into the emulsion droplets where TATP degradation occurs. EZVM systems are ideal for degrading dry TATP crystals that may be present on a carpet or door entrance. Both the neat metal system and the emulsion system (EZVM) degrade TATP in an aqueous slurry.
Official Gazette of the U.S. Patent and Trademark Office
ACETONE; DESTRUCTION; EXPLOSIVES; PEROXIDES; DISSOLVING; HYDROPHOBICITY
20110023524 Princeton Univ., NJ United States
Thermally exfoliated graphite oxide
Prud'Homme, Robert K., Inventor; Aksay, Ilhan A., Inventor; Abdala, Ahmed, Inventor; November 29, 2011; In English
Contract(s)/Grant(s): NCC1-02037
Patent Info.: June 1, 2010US-Patent-8,066,964; US-Patent-Appl-SN-12/791,190
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023524
A modified graphite oxide material contains a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m/g, wherein the thermally exfoliated graphite oxide displays no signature of the original graphite and/or graphite oxide, as determined by X-ray diffraction.
Official Gazette of the U.S. Patent and Trademark Office
DISPLAY DEVICES; GRAPHITE; OXIDES; X RAY DIFFRACTION
20110023525 California Inst. of Tech., Pasadena, CA United States
CMOS active pixel sensor type imaging system on a chip
Fossum, Eric R., Inventor; Nixon, Robert, Inventor; November 29, 2011; In English
Patent Info.: April 9, 2009US-Patent-RE42,974; US-Patent-Appl-SN-12/421,477
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023525
A single chip camera which includes an .[.intergrated.]. .Iadd.integrated .Iaddend.image acquisition portion and control portion and which has double sampling/noise reduction capabilities thereon. Part of the .[.intergrated.]. .Iadd.integrated .Iaddend.structure reduces the noise that is picked up during imaging.
Official Gazette of the U.S. Patent and Trademark Office
CMOS; IMAGING TECHNIQUES; NOISE REDUCTION; SYSTEMS-ON-A-CHIP; PIXELS; CAMERAS
20110023527 NASA Johnson Space Center, Houston, TX, United States
The International Space Station Research Opportunities and Accomplishments
Alleyne, Camille W.; [2011]; In English; NSBE Aeropsace Systems Conference, 1-4 Feb. 2012, Los Angeles, CA, United States; Original contains color illustrations
Report No.(s): JSC-CN-25364; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023527
In 2010, the International Space Station (ISS) construction and assembly was completed to become a world-class scientific research laboratory. We are now in the era of utilization of this unique platform that facilitates ground-breaking research in the microgravity environment. There are opportunities for NASA-funded research; research funded under the auspice of the United States National Laboratory; and research funded by the International Partners - Japan, Europe, Russia and Canada. The ISS facilities offer an opportunity to conduct research in a multitude of disciplines such as biology and biotechnology, physical science, human research, technology demonstration and development; and earth and space science. The ISS is also a unique resource for educational activities that serve to motivate and inspire students to pursue careers in Science, Technology, Engineering and Mathematics. Even though we have just commenced full utilization of the ISS as a science laboratory, early investigations are yielding major results that are leading to such things as vaccine development, improved cancer drug delivery methods and treatment for debilitating diseases, such as Duchenne's Muscular Dystrophy. This paper
Author
INTERNATIONAL SPACE STATION; MICROGRAVITY; BIOTECHNOLOGY; EARTH SCIENCES; EDUCATION; DISEASES
20110023528 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The X-Ray Evolution of the Symbiotic Star V 407 Cygni During Its 2010 Outburst
Mukai, K.; Nelson, T.; Chomiuk, L.; Donato, D.; Sokoloski, J.; [2011]; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NNG06EO90A
Report No.(s): GSFC.JA.5438.2011; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023528
We present a summary of Swift and Suzaku X-ray observations of the 2010 nova outburst of the symbiotic star, V 407 Cyg. The Suzaku spectrum obtained on day 30 indicates the presence of the supersoft component from the white dwarf surface, as well as optically thin component from the shock between the nova ejecta and the Mira wind. The Swift observations then allow us to track the evolution of both components from day 4 to day 150. Most notable is the sudden brightening of the optically think component around day 20. We identify this as the time when the blast wave reached the immediate vicinity of the photosphere of the Mira. We have developed a simplified model of the blast wave-wind interaction that can reproduce the gross features of the X-ray evolution of V407 Cyg. If the model is correct, the binary separation is likely to be large and the mass loss rate of the Mira is likely to be relatively low.
Author
DETONATION WAVES; PHOTOSPHERE; SYMBIOTIC STARS; WAVE INTERACTION; CYGNUS CONSTELLATION; X RAYS; SHOCK WAVES
20110023529 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Fall and the Rise of X-Rays from Dwarf Novae in Outburst: RXTE Observations of VW Hydri and WW Ceti
Fertig, D.; Mukai, K.; Nelson, T.; Cannizzo, J. K.; [2011]; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NNG06EO90A
Report No.(s): GSFC.JA.5443.2011; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023529
In a dwarf nova, the accretion disk around the white dwarf is a source of ultraviolet, optical, and infrared photons, but is never hot enough to emit X-rays. Observed X-rays instead originate from the boundary layer between the disk and the white dwarf. As the disk switches between quiescence and outburst states, the 2-10 keV X-ray flux is usually seen to be anti-correlated with the optical brightness. Here we present RXTE monitoring observations of two dwarf novae, VW Hyi and WW Cet, confirming the optical/X-ray anti-correlation in these two systems. However, we do not detect any episodes of increased hard X-ray flux on the rise (out of two possible chances for WW Cet) or the decline (two for WW Cet and one for VW Hyi) from outburst, attributes that are clearly established in SS Cyg. The addition of these data to the existing literature establishes the fact that the behavior of SS Cyg is the exception, rather than the archetype as is often assumed. We speculate that only dwarf novae with a massive white dwarf may show these hard X-ray spikes.
Author
ACCRETION DISKS; DWARF NOVAE; X RAY TIMING EXPLORER; BOUNDARY LAYERS; CYGNUS CONSTELLATION; INFRARED RADIATION
20110023533 NASA Johnson Space Center, Houston, TX, United States
Evidence of Space Weathering Processes Across the Surface of Vesta
Pieters, Carle M.; Blewett, David T.; Gaffey, Michael; Mittlefehldt, David W.; CristinaDeSanctis, Maria; Reddy, Vishnu; Coradini, Angioletta; Nathues, Andreas; Denevi, Brett W.; Li, Jian-Yang; McCord, Thomas B.; Marchi, Simone; Palmer, Eric E.; Sunshine, Jessica M.; Filacchione, Gianrico; Ammannito, Eleonora; Raymond, Carol A.; Russell, Christopher T.; December 05, 2011; In English; Fall 2011 Meeting ofthe American Geophysical Unior, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): JSC-CN-25370; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023533
As NASA s Dawn spacecraft explores the surface of Vesta, it has become abundantly clear that Vesta is like no other planetary body visited to date. Dawn is collecting global data at increasingly higher spatial resolution during its one-year orbital mission. The bulk properties of Vesta have previously been linked to the HED meteorites through remote mineral characterization of its surface from Earth-based spectroscopy. A principal puzzle has been why Vesta exhibits relatively unweathered diagnostic optical features compared to other large asteroids. Is this due to the composition of this proto-planet or the space environment at Vesta? Alteration or weathering of materials in space normally develops as the products of several processes accumulate on the surface or in an evolving particulate regolith, transforming the bedrock into fragmental material with properties that may be measurably different from the original. Data from Dawn reveal that the regolith of Vesta is exceptionally diverse. Regional surface units are observed that have not been erased by weathering with time. Several morphologically-fresh craters have excavated bright, mafic-rich materials and exhibit bright ray systems. Some of the larger craters have surrounding subdued regions (often asymmetric) that are lower in albedo and relatively red-sloped in the visible while exhibiting weaker mafic signatures. Several other prominent craters have rim exposures containing very dark material and/or display a system of prominent dark rays. Most, but not all, dark areas associated with craters exhibit significantly lower spectral contrast, suggesting that either a Vesta lithology with an opaque component has been exposed locally or that the surface has been contaminated by a relatively dark impactor. Similarly, most, but not all, bright areas associated with craters exhibit enhanced mafic signatures compared to surroundings. On a regional scale, the large south polar structure and surrounding terrain exhibit relatively strong mafic absorption features, suggesting either a concentration of mafic materials or that materials exposed have been less affected by space weathering products. These combined initial observations indicate some space weathering processes are active in this part of the main asteroid belt, but are highly variable across the surface of Vesta. Such processes include: impacts from wandering asteroidal debris and local mixing at both micro- and macro-scales, irradiation by solar wind and galactic particles, production and distribution of impact breccias or melt products, and local movement of materials to gravity lows (gradual as well as sudden).
Author
VESTA ASTEROID; MINERALOGY; DATA ACQUISITION; PARTICULATES; REGOLITH; SPATIAL RESOLUTION; AEROSPACE ENVIRONMENTS; EXPOSURE
20110023534 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Orbit Determination of the SELENE Satellites Using Multi-Satellite Data Types and Evaluation of SELENE Gravity Field Models
Goossens, S.; Matsumoto, K.; Noda, H.; Araki, H.; Rowlands, D. D.; Lemoine, F. G.; Journal of Geodesy; February 08, 2011; vol. Volume 85; issue No. 8; pp. 487-50; In English; Original contains black and white illustrations
Contract(s)/Grant(s): JSPS-20244073
Report No.(s): GSFC.JA.5448.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1007/s00190-011-0446-2
The SELENE mission, consisting of three separate satellites that use different terrestrial-based tracking systems, presents a unique opportunity to evaluate the contribution of these tracking systems to orbit determination precision. The tracking data consist of four-way Doppler between the main orbiter and one of the two sub-satellites while the former is over the far side, and of same-beam differential VLBI tracking between the two sub-satellites. Laser altimeter data are also used for orbit determination. The contribution to orbit precision of these different data types is investigated through orbit overlap analysis. It is shown that using four-way and VLBI data improves orbit consistency for all satellites involved by reducing peak values in orbit overlap differences that exist when only standard two-way Doppler and range data are used. Including laser altimeter data improves the orbit precision of the SELENE main satellite further, resulting in very smooth total orbit errors at an average level of 18m. The multi-satellite data have also resulted in improved lunar gravity field models, which are assessed through orbit overlap analysis using Lunar Prospector tracking data. Improvements over a pre-SELENE model are shown to be mostly in the along-track and cross-track directions. Orbit overlap differences are at a level between 13 and 21 m with the SELENE models, depending on whether l-day data overlaps or I-day predictions are used.
Author
VERY LONG BASE INTERFEROMETRY; ORBIT DETERMINATION; LASER ALTIMETERS; TRACKING (POSITION); PRECISION; LUNAR GRAVITATION; GRAVITATIONAL FIELDS; LUNAR PROSPECTOR
20110023535 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Climate Hazard Assessment for Stakeholder Adaptation Planning in New York City
Horton, Radley M.; Gornitz, Vivien; Bader, Daniel A.; Ruane, Alex C.; Goldberg, Richard; Rosenzweig, Cynthia; [2011]; In English; Original contains color illustrations
Report No.(s): GSFC.JA.5451.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023535
This paper describes a time-sensitive approach to climate change projections, developed as part of New York City's climate change adaptation process, that has provided decision support to stakeholders from 40 agencies, regional planning associations, and private companies. The approach optimizes production of projections given constraints faced by decision makers as they incorporate climate change into long-term planning and policy. New York City stakeholders, who are well-versed in risk management, helped pre-select the climate variables most likely to impact urban infrastructure, and requested a projection range rather than a single 'most likely' outcome. The climate projections approach is transferable to other regions and consistent with broader efforts to provide climate services, including impact, vulnerability, and adaptation information. The approach uses 16 Global Climate Models (GCMs) and three emissions scenarios to calculate monthly change factors based on 30-year average future time slices relative to a 30- year model baseline. Projecting these model mean changes onto observed station data for New York City yields dramatic changes in the frequency of extreme events such as coastal flooding and dangerous heat events. Based on these methods, the current 1-in-10 year coastal flood is projected to occur more than once every 3 years by the end of the century, and heat events are projected to approximately triple in frequency. These frequency changes are of sufficient magnitude to merit consideration in long-term adaptation planning, even though the precise changes in extreme event frequency are highly uncertain
Author
CLIMATE CHANGE; CLIMATE MODELS; HAZARDS; NEW YORK CITY (NY); RISK MANAGEMENT
20110023536 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Magnetic Field-Line Lengths in Interplanetary Coronal Mass Ejections Inferred from Energetic Electron Events
Kahler, S. W.; Haggerty, D. K.; Richardson, I. G.; The Astrophysical Journal; August 2011; vol. Volume 736; issue No. 2; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NNG06EO90A
Report No.(s): GSFC.JA.5453.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1088/0004-637X/736/2/106
About one quarter of the observed interplanetary coronal mass ejections (ICMEs) are characterized by enhanced magnetic fields that smoothly rotate in direction over timescales of about 10-50 hr. These ICMEs have the appearance of magnetic flux ropes and are known as "magnetic clouds" (MCs). The total lengths of MC field lines can be determined using solar energetic particles of known speeds when the solar release times and the I AU onset times of the particles are known. A recent examination of about 30 near-relativistic (NR) electron events in and near 8 MCs showed no obvious indication that the field-line lengths were longest near the MC boundaries and shortest at the MC axes or outside the MCs, contrary to the expectations for a flux rope. Here we use the impulsive beamed NR electron events observed with the Electron Proton and Alpha Monitor instrument on the Advanced Composition Explorer spacecraft and type III radio bursts observed on the Wind spacecraft to determine the field-line lengths inside ICMEs included in the catalog of Richardson & Cane. In particular, we extend this technique to ICMEs that are not MCs and compare the field-line lengths inside MCs and non-MC ICMEs with those in the ambient solar wind outside the ICMEs. No significant differences of field-line lengths are found among MCs, ICMEs, and the ambient solar wind. The estimated number of ICME field-line turns is generally smaller than those deduced for flux-rope model fits to MCs. We also find cases in which the electron injections occur in solar active regions CARs) distant from the source ARs of the ICMEs, supporting CME models that require extensive coronal magnetic reconnection with surrounding fields. The field-line lengths are found to be statistically longer for the NR electron events classified as ramps and interpreted as shock injections somewhat delayed from the type III bursts. The path lengths of the remaining spike and pulse electron events are compared with model calculations of solar wind field-line lengths resulting from turbulence and found to be in good agreement.
Author
CORONAL MASS EJECTION; MAGNETIC FIELDS; ASTRONOMICAL MODELS; SOLAR WIND; MAGNETIC FLUX; EXPLORER SATELLITES; VELOCITY DISTRIBUTION; WIND VELOCITY
20110023537 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Properties of Large Amplitude Whistler Mode Waves in the Magnetosphere: Propagation and Relationship with Geomagnetic Activity
Wilson, L. B., III; Cattell, C. A.; Kellogg, P. J.; Wygant, J. R.; Goetz, K.; Breneman, A.; Kersten, K.; Geophysical Research Letters; September 08, 2011; vol. Volume 38; issue L17107; In English; Original contains color illustrations
Contract(s)/Grant(s): NNX07AU72H; NNX07AI05G
Report No.(s): GSFC.JA.5458.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023537
http://dx.doi.org/10.1029/2011GL048671
Wepresent resultsof a studyof the characteristicsof very large amplitude whistler mode waves inside the terrestrial magnetosphere at radial distances of less than 15 RE using waveform capture data from the Wind spacecraft. We observed 247 whistler mode waves with at least one electric field component (105/247 had !80 mV/m peak!to!peak amplitudes) and 66 whistler mode waves with at least one search coil magnetic field component (38/66 had !0.8 nT peak!to!peak amplitudes). Wave vectors determined from events with three magnetic field components indicate that 30/46 propagate within 20 of the ambient magnetic field, though some are more oblique (up to "50 ). No relationship was observed between wave normal angle and GSM latitude. 162/247 of the large amplitude whistler mode waves were observed during magnetically active periods (AE > 200 nT). 217 out of 247 total whistler mode waves examined were observed inside the radiation belts. We present a waveform capture with the largest whistler wave magnetic field amplitude (^8 nT peak!to!peak) ever reported in the radiation belts. The estimated Poynting flux magnitude associated with this wave is ^300 mW/m2, roughly four orders of magnitude above estimates from previous satellite measurements. Such large Poynting flux values are consistent with rapid energization of electrons.
Author
FLUX QUANTIZATION; MAGNETIC FIELDS; GEOMAGNETISM; WHISTLERS; RADIATION BELTS; WAVEFORMS
20110023538 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Large Amplitude Whistlers in the Magnetosphere Observed with Wind-Waves
Kellogg, P. J.; Cattell, C. A.; Goetz, K.; Monson, S. J.; Wilson, L. B., III; Journal of Geophysical Research; September 21, 2011; ISSN 0148-0227; vol. Volume 116; issue A09224; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NNX07AF23G; NNX11AB46G; NNX07AU72H; NNX07AM97G; NNX08AT81G
Report No.(s): GSFC.JA.5459.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1029/2010JA015919
We describe the results of a statistical survey of Wind-Waves data motivated by the recent STEREO/Waves discovery of large-amplitude whistlers in the inner magnetosphere. Although Wind was primarily intended to monitor the solar wind, the spacecraft spent 47 h inside 5 R(sub E) and 431 h inside 10 R(sub E) during the 8 years (1994-2002) that it orbited the Earth. Five episodes were found when whistlers had amplitudes comparable to those of Cattell et al. (2008), i.e., electric fields of 100 m V/m or greater. The whistlers usually occurred near the plasmapause. The observations are generally consistent with the whistlers observed by STEREO. In contrast with STEREO, Wind-Waves had a search coil, so magnetic measurements are available, enabling determination of the wave vector without a model. Eleven whistler events with useable magnetic measurements were found. The wave vectors of these are distributed around the magnetic field direction with angles from 4 to 48deg. Approximations to observed electron distribution functions show a Kennel-Petschek instability which, however, does not seem to produce the observed whistlers. One Wind episode was sampled at 120,000 samples/s, and these events showed a signature that is interpreted as trapping of electrons in the electrostatic potential of an oblique whistler. Similar waveforms are found in the STEREO data. In addition to the whistler waves, large amplitude, short duration solitary waves (up to 100 mV/m), presumed to be electron holes, occur in these passes, primarily on plasma sheet field lines mapping to the auroral zone.
Author
AIR WATER INTERACTIONS; MAGNETIC FIELD CONFIGURATIONS; ELECTRON DISTRIBUTION; SOLITARY WAVES; WAVEFORMS; WHISTLERS; SOLAR WIND; PLASMAPAUSE; ELECTRIC FIELDS; AURORAL ZONES
20110023539 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Heterogeneous Distributions of Amino Acids Provide Evidence of Multiple Sources Within the Almahata Sitta Parent Body, Asteroid 2008 TC(sub 3)
Burton, Aaron S.; Glavin, Daniel P.; Callahan, Michael P.; Dworkin, Jason P.; Jenniskens, Peter; Shaddad, Muawia H.; Meteoricitcs and Planetary Science; October 07, 2011; vol. Volume 46; issue Iss. 11; pp. 1703-171; In English; Original contains black and white illustrations
Report No.(s): GSFC.JA.5470.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1111/j.1945-5100.2011.01257.x
Two new fragments of the Almahata Sitta meteorite and a sample of sand from the related strewn field in the Nubian Desert, Sudan, were analyzed for two to six carbon aliphatic primary amino acids by ultrahigh performance liquid chromatography with UV-fluorescence detection and time-of-flight mass spectrometry (LC-FT/ToF-MS). The distribution of amino acids in fragment #25, an H5 ordinary chondrite, and fragment #27, a polymict ureilite, were compared with results from the previously analyzed fragment #4, also a polymict ureilite. All three meteorite fragments contain 180-270 parts-per-billion (ppb) of amino acids, roughly 1000-fold lower than the total amino acid abundance of the Murchison carbonaceous chondrite. All of the Almahata Sitta fragments analyzed have amino acid distributions that differ from the Nubian Desert sand, which primarily contains L-alpha-amino acids. In addition, the meteorites contain several amino acids that were not detected in the sand, indicating that many of the amino acids are extraterrestrial in origin. Despite their petrological differences, meteorite fragments #25 and #27 contain similar amino acid compositions; however, the distribution of amino acids in fragment #27 was distinct from those in fragment #4, even though both arc polymict ureilites from the same parent body. Unlike in CM2 and CR2/3 meteorites, there are low relative abundances of alpha-amino acids in the Almahata Sitta meteorite fragments, which suggest that Strecker-type chemistry was not a significant amino acid formation mechanism. Given the high temperatures that asteroid 2008 TC3 appears to have experienced and lack of evidence for aqueous alteration on the asteroid, it is possible that the extraterrestrial amino acids detected in Almahata Sitta were formed by Fischer-Tropsch/Haber-Bosch type gas-grain reactions at elevated temperatures.
Author
CARBONACEOUS CHONDRITES; ASTEROIDS; AMINO ACIDS; LIQUID CHROMATOGRAPHY; TIME OF FLIGHT SPECTROMETERS; METEORITES; PETROLOGY; HIGH TEMPERATURE; MASS SPECTROSCOPY
20110023540 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Interannual to Decadal Variability of Atlantic Water in the Nordic and Adjacent Seas
Carton, James A.; Chepurin, Gennady A.; Reagan, James; Haekkinen, Sirpa; September 06, 2011; In English; Original contains color illustrations
Contract(s)/Grant(s): NSF OCE0752209
Report No.(s): GSFC.JA.5475.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023540
Warm salty Atlantic Water is the main source water for the Arctic Ocean and thus plays an important role in the mass and heat budget of the Arctic. This study explores interannual to decadal variability of Atlantic Water properties in the Nordic Seas area where Atlantic Water enters the Arctic, based on a reexamination of the historical hydrographic record for the years 1950-2009, obtained by combining multiple data sets. The analysis shows a succession of four multi-year warm events where temperature anomalies at 100m depth exceed 0.4oC, and three cold events. Three of the four warm events lasted 3-4 years, while the fourth began in 1999 and persists at least through 2009. This most recent warm event is anomalous in other ways as well, being the strongest, having the broadest geographic extent, being surface-intensified, and occurring under exceptional meteorological conditions. Three of the four warm events were accompanied by elevated salinities consistent with enhanced ocean transport into the Nordic Seas, with the exception of the event spanning July 1989-July 1993. Of the three cold events, two lasted for four years, while the third lasted for nearly 14 years. Two of the three cold events are associated with reduced salinities, but the cold event of the 1960s had elevated salinities. The relationship of these events to meteorological conditions is examined. The results show that local surface heat flux variations act in some cases to reinforce the anomalies, but are too weak to be the sole cause.
Author
ARCTIC OCEAN; ARCTIC REGIONS; PERIODIC VARIATIONS; OCEANS; HYDROGRAPHY; HEAT FLUX; SEAS; HEAT BUDGET
20110023541 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Fog and Cloud Induced Aerosol Modification Observed by AERONET
Eck, T. F.; Holben, B. N.; Reid, J. S.; Giles, D. M.; Rivas, M. A.; Singh, R. P.; Tripathi, S. N.; Bruegge, C. J.; Platnick, S. E.; Arnold, G. T.; Krotkov, N. A.; Carn, S. A.; Sinyuk, A.; Dubovik, O.; Arola, A.; Schafer, J. S.; Artaxo, P.; Smirnov, A.; Chen, H.; Goloub, P.; [2011]; In English; Original contains color illustrations
Contract(s)/Grant(s): UTA-Mayor 4721
Report No.(s): GSFC.JA.5476.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023541
Large fine mode (sub-micron radius) dominated aerosols in size distributions retrieved from AERONET have been observed after fog or low-altitude cloud dissipation events. These column-integrated size distributions have been obtained at several sites in many regions of the world, typically after evaporation of low altitude cloud such as stratocumulus or fog. Retrievals with cloud processed aerosol are sometimes bimodal in the accumulation mode with the larger size mode often approx.0.4 - 0.5 microns radius (volume distribution); the smaller mode typically approx.0.12 to aprrox.0.20 microns may be interstitial aerosol that were not modified by incorporation in droplets and/or aerosol that are less hygroscopic in nature. Bimodal accumulation mode size distributions have often been observed from in situ measurements of aerosols that have interacted with clouds, and AERONET size distribution retrievals made after dissipation of cloud or fog are in good agreement with particle sizes measured by in situ techniques for cloud-processed aerosols. Aerosols of this type and large size range (in lower concentrations) may also be formed by cloud processing in partly cloudy conditions and may contribute to the shoulder of larger size particles in the accumulation mode retrievals, especially in regions where sulfate and other soluble aerosol are a significant component of the total aerosol composition. Observed trends of increasing aerosol optical depth (AOD) as fine mode radius increased suggests higher AOD in the near cloud environment and therefore greater aerosol direct radiative forcing than typically obtained from remote sensing, due to bias towards sampling at low cloud fraction.
Author
AEROSOLS; FOG; OPTICAL THICKNESS; REMOTE SENSING; STRATOCUMULUS CLOUDS; DROPS (LIQUIDS); FOG DISPERSAL; HYGROSCOPICITY; RADIATIVE FORCING; RADII
20110023542 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Relationships Between Seed Weight, Germination Potential and Biochemical Reserves of Maritime Pine in Morocco: Elements for Tree Seedlings Improvement
Wahid, Nadya; Bounoua, Lahouari; [2011]; In English; Original contains color illustrations
Report No.(s): GSFC.JA.5477.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023542
Selection of quality seeds in breeding programs can significantly improve seedling productivity. Germination and biochemical analyses on seeds from ten natural populations of maritime pine (Pinus pinaster Ait.) in Morocco reveals significant differences among populations in seed weight, germination characters and protein content in both dry seeds and megagametophytes. During germination, the mobilization of protein content in megagametophyte is significantly different among populations than sugar content. A strong positive correlation between the germination capacity and the protein content in both dry seeds and megagametophytes indicates that the best populations in term of germination capacity may also be the richest in protein content. The present study finds that seed weight is not a good indicator for quality seed selection, nor is it recommended to increase the degree of germinability. Our results suggest that the pine population in southern Morocco might have adapted to drought conditions as it is characterized by heavy seed weight and lower speed of protein content mobilization in megagametophyte compared to northern populations growing in temperate climate.
Author
SEEDLINGS (BOTANY); TREES (PLANTS); GERMINATION; CONIFERS; BIOCHEMISTRY; BREEDING (REPRODUCTION)
20110023543 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Kinetic-Scale Magnetic Turbulence and Finite Larmor Radius Effects at Mercury
Uritsky, V. M.; Slavin, J. A.; Khazanov, G. V.; Donovan, E. F.; Boardsen, S. A.; Anderson, B. J.; Korth, H.; Journal of Geophysical Research; September 29, 2011; ISSN 0148-0227; vol. Volume 116; issue A09236; In English; Original contains color illustrations
Report No.(s): GSFC.JA.5483.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1029/2011JA016744
We use a nonstationary generalization of the higher-order structure function technique to investigate statistical properties of the magnetic field fluctuations recorded by MESSENGER spacecraft during its first flyby (01/14/2008) through the near-Mercury space environment, with the emphasis on key boundary regions participating in the solar wind - magnetosphere interaction. Our analysis shows, for the first time, that kinetic-scale fluctuations play a significant role in the Mercury's magnetosphere up to the largest resolvable timescale (approx.20 s) imposed by the signal nonstationariry, suggesting that turbulence at this plane I is largely controlled by finite Larmor radius effects. In particular, we report the presence of a highly turbulent and extended foreshock system filled with packets of ULF oscillations, broad-band intermittent fluctuations in the magnetosheath, ion-kinetic turbulence in the central plasma sheet of Mercury's magnetotail, and kinetic-scale fluctuations in the inner current sheet encountered at the outbound (dawn-side) magnetopause. Overall, our measurements indicate that the Hermean magnetosphere, as well as the surrounding region, are strongly affected by non-MHD effects introduced by finite sizes of cyclotron orbits of the constituting ion species. Physical mechanisms of these effects and their potentially critical impact on the structure and dynamics of Mercury's magnetic field remain to be understood.
Author
MAGNETOHYDRODYNAMICS; MERCURY (PLANET); MESSENGER (SPACECRAFT); SOLAR WIND; PLASMA INTERACTIONS; LARMOR RADIUS; MAGNETOPAUSE; PLANETARY MAGNETIC FIELDS
20110023544 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Pickup Ion Distributions from Three Dimensional Neutral Exospheres
Hartle, R. E.; Sarantos, M.; Sittler, E. C., Jr.; Journal of Geophysical Research; October 07, 2011; vol. Volume 116; issue A10101; In English
Report No.(s): GSFC,JA.5482.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1029/2011JA016859
Pickup ions formed from ionized neutral exospheres in flowing plasmas have phase space distributions that reflect their source's spatial distributions. Phase space distributions of the ions are derived from the Vlasov equation with a delta function source using three.dimensional neutral exospheres. The ExB drift produced by plasma motion picks up the ions while the effects of magnetic field draping, mass loading, wave particle scattering, and Coulomb collisions near a planetary body are ignored. Previously, one.dimensional exospheres were treated, resulting in closed form pickup ion distributions that explicitly depend on the ratio rg/H, where rg is the ion gyroradius and H is the neutral scale height at the exobase. In general, the pickup ion distributions, based on three.dimensional neutral exospheres, cannot be written in closed form, but can be computed numerically. They continue to reflect their source's spatial distributions in an implicit way. These ion distributions and their moments are applied to several bodies, including He(+) and Na(+) at the Moon, H(+2) and CH(+4) at Titan, and H+ at Venus. The best places to use these distributions are upstream of the Moon's surface, the ionopause of Titan, and the bow shock of Venus.
Author
ION DISTRIBUTION; EXOSPHERE; VLASOV EQUATIONS; IONS; MAGNETIC FIELDS; PARTICLE MOTION; PLASMAS (PHYSICS); SHOCK WAVES; SPATIAL DISTRIBUTION; WAVE SCATTERING
20110023545 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Thermal Properties of A Solar Coronal Cavity Observed with the X-Ray Telescope on Hinode
Reeves, Katherine K.; Gibson, Sarah E.; Kucera, Theresa A.; Hudson, Hugh S.; Kano, Ryouhei; [2011]; In English; Original contains color illustrations
Contract(s)/Grant(s): NNM07AB07C
Report No.(s): GSFC.JA.5490.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023545
Coronal cavities are voids in coronal emission often observed above high latitude filament channels. Sometimes, these cavities have areas of bright X-ray emission in their centers. In this study, we use data from the X-ray Telescope (XRT) on the Hinode satellite to examine the thermal emission properties of a cavity observed during July 2008 that contains bright X-ray emission in its center. Using ratios of XRT filters, we find evidence for elevated temperatures in the cavity center. The area of elevated temperature evolves from a ring-shaped structure at the beginning of the observation, to an elongated structure two days later, finally appearing as a compact round source four days after the initial observation. We use a morphological model to fit the cavity emission, and find that a uniform structure running through the cavity does not fit the observations well. Instead, the observations are reproduced by modeling several short cylindrical cavity "cores" with different parameters on different days. These changing core parameters may be due to some observed activity heating different parts of the cavity core at different times. We find that core temperatures of 1.75 MK, 1.7 MK and 2.0 MK (for July 19, July 21 and July 23, respectively) in the model lead to structures that are consistent with the data, and that line-of-sight effects serve to lower the effective temperature derived from the filter ratio.
Author
SOLAR CORONA; THERMAL EMISSION; CAVITIES; RING STRUCTURES; THERMODYNAMIC PROPERTIES; X RAY TELESCOPES; CYLINDRICAL BODIES
20110023546 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Effect of Different Operations Modes on Science Capabilities During the 2010 Desert-RATS Test: Insights from the Geologist Crewmembers
Bleacher, Jacob E.; Hurtado, Jose M., Jr.; Young, Kelsey E.; Rice, James W., Jr.; Garry, W. Brent; [2011]; In English; Original contains color illustrations
Contract(s)/Grant(s): LPI/USRA 02173-07NNX09AV09A; NNA09DB33A; NNX10AK72H
Report No.(s): GSFC.JA.5492.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023546
The 2010 Desert RATS field test utilized two Space Exploration Vehicles (prototype planetary rovers) and four crewmembers (2 per rover) to conduct a geologic traverse across northern Arizona while testing continuous and twice-per-day communications paired with operation modes of separating and exploring individually (Divide & Conquer) and exploring together (Lead & Follow), respectively. This report provides qualitative conclusions from the geologist crewmembers involved in this test as to how these modes of communications and operations affected our ability to conduct field geology. Each mode of communication and operation provided beneficial capabilities that might be further explored for future Human Spaceflight Missions to other solar system objects. We find that more frequent interactions between crews and an Apollo-style Science Team on the Earth best enables scientific progress during human exploration. However, during multiple vehicle missions, this communication with an Earth-based team of scientists, who represent "more minds on the problem", should not come at the exclusion of (or significantly decrease) communication between the crewmembers in different vehicles who have the "eyes on the ground". Inter-crew communications improved when discussions with a backroom were infrequent. Both aspects are critical and cannot be mutually exclusive. Increased vehicle separation distances best enable encounters with multiple geologic units. However, seemingly redundant visits by multiple vehicles to the same feature can be utilized to provide improved process-related observations about the development and modification of the local terrain. We consider the value of data management, transfer, and accessibility to be the most important lesson learned. Crews and backrooms should have access to all data and related interpretations within the mission in as close to real-time conditions as possible. This ensures that while on another planetary surface, crewmembers are as educated as possible with respect to the observations and data they will need to collect at any moment.
Author
FIELD TESTS; GEOLOGY; VOICE COMMUNICATION; INFORMATION FLOW; SCIENTISTS
20110023548 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Evidence for Dark Energy from the Cosmic Microwave Background Alone Using the Atacama Cosmology Telescope Lensing Measurements
Sherwin, Blake D.; Dunkley, Joanna; Das, Sudeep; Appel, John W.; Bond, J. Richard; Carvalho, C. Sofia; Devlin, Mark J.; Duenner, Rolando; Essinger-Hileman, Thomas; Fowler, Joesph J.; Hajian, Amir; Halpern, Mark; Hasselfield, Matthew; Hincks, Adam D.; Hlozek, Renee; Hughes, John P.; Irwin, Kent D.; Klein, Jeff; Kosowsky, Arthur; Marriage, Tobias A.; Marsden, Danica; Moodley, Kavilan; Menanteau, Felipe; Niemack, Michael D.; Wollack, Ed.; et. al; [2011]; In English; Original contains color illustrations
Contract(s)/Grant(s): DE-AC3-76SF00515NNX08AH30G; NSF AST-0408698; NSF PHY-0355328; NSF AST-0707731; NSF PIRE-0507768; NSF AST-0546035
Report No.(s): GSFC.JA.5509.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023548
For the first time, measurements of the cosmic microwave background radiation (CMB) alone favor cosmologies with w = -1 dark energy over models without dark energy at a 3.2-sigma level. We demonstrate this by combining the CMB lensing deflection power spectrum from the Atacama Cosmology Telescope with temperature and polarization power spectra from the "Wilkinson Microwave Anisotropy Probe. The lensing data break the geometric degeneracy of different cosmological models with similar CMB temperature power spectra. Our CMB-only measurement of the dark energy density Omega(delta) confirms other measurements from supernovae, galaxy clusters and baryon acoustic oscillations, and demonstrates the power of CMB lensing as a new cosmological tool.
Author
COSMIC MICROWAVE BACKGROUND RADIATION; DARK ENERGY; GALACTIC CLUSTERS; TELESCOPES; COSMOLOGY; ASTRONOMICAL MODELS; MICROWAVE ANISOTROPY PROBE
20110023549 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Constraining the Absolute Orientation of eta Carinae's Binary Orbit: A 3-D Dynamical Model for the Broad [Fe III] Emission
Madura, T. I.; Gull, T. R.; Owocki, S. P.; Groh, J. H.; Okazaki, A. T.; Russell, C. M. P.; September 29, 2011; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NAS5-26555NNK11AC40G
Report No.(s): GSFC.JA.5510.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023549
We present a three-dimensional (3-D) dynamical model for the broad [Fe III] emission observed in Eta Carinae using the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS). This model is based on full 3-D Smoothed Particle Hydrodynamics (SPH) simulations of Eta Car's binary colliding winds. Radiative transfer codes are used to generate synthetic spectro-images of [Fe III] emission line structures at various observed orbital phases and STIS slit position angles (PAs). Through a parameter study that varies the orbital inclination i, the PA(theta) that the orbital plane projection of the line-of-sight makes with the apastron side of the semi-major axis, and the PA on the sky of the orbital axis, we are able, for the first time, to tightly constrain the absolute 3-D orientation of the binary orbit. To simultaneously reproduce the blue-shifted emission arcs observed at orbital phase 0.976, STIS slit PA = +38deg, and the temporal variations in emission seen at negative slit PAs, the binary needs to have an i approx. = 130deg to 145deg, Theta approx. = -15deg to +30deg, and an orbital axis projected on the sky at a P A approx. = 302deg to 327deg east of north. This represents a system with an orbital axis that is closely aligned with the inferred polar axis of the Homunculus nebula, in 3-D. The companion star, Eta(sub B), thus orbits clockwise on the sky and is on the observer's side of the system at apastron. This orientation has important implications for theories for the formation of the Homunculus and helps lay the groundwork for orbital modeling to determine the stellar masses.
Author
HYDRODYNAMICS; COMPANION STARS; STELLAR MASS; LINE OF SIGHT; SPACEBORNE TELESCOPES; THREE DIMENSIONAL MODELS; NEBULAE; HUBBLE SPACE TELESCOPE; RADIATIVE TRANSFER
20110023550 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Atacama Cosmology Telescope: Physical Properties and Purity of a Galaxy Cluster Sample Selected Via the Sunyaev-Zel'Dovich Effect
Menanteau, Felipe; Gonzalez, Jorge; Juin, Jean-Baptiste; Marriage, Tobias; Reese, Erik D.; Acquaviva, Viviana; Aguirre, Paula; Appel, John Willam; Baker, Andrew J.; Barrientos, L. Felipe; Battistelli, Elia S.; Bond, Richard; Das, Supeed; Deshpande, Amruta J.; Devlin, Mark J.; Dicker, Simon; Dunkley, Joanna; Duenner, Rolando; Essinger-Hileman, Thomas; Fowler, Joseph W.; Hajian, Amir; Halpern, Mark; Hasselfield, Matthew; Hernandez-Monteagudo, Carlos; Wollack, Ed; et al.; June 25, 2010; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NNX08AX55G; NNX08AX72G; NSF AST-0408698; NSF PHY-0355328; NSF AST-0707731; NSF PIRE-0507768
Report No.(s): GSFC.JA.5515.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023550
We present optical and X-ray properties for the first confirmed galaxy cluster sample selected by the Sunyaev-Zel'dovich Effect from 148 GHz maps over 455 square degrees of sky made with the Atacama Cosmology Telescope. These maps. coupled with multi-band imaging on 4-meter-class optical telescopes, have yielded a sample of 23 galaxy clusters with redshifts between 0.118 and 1.066. Of these 23 clusters, 10 are newly discovered. The selection of this sample is approximately mass limited and essentially independent of redshift. We provide optical positions, images, redshifts and X-ray fluxes and luminosities for the full sample, and X-ray temperatures of an important subset. The mass limit of the full sample is around 8.0 x 10(exp 14) Stellar Mass. with a number distribution that peaks around a redshift of 0.4. For the 10 highest significance SZE-selected cluster candidates, all of which are optically confirmed, the mass threshold is 1 x 10(exp 15) Stellar Mass and the redshift range is 0.167 to 1.066. Archival observations from Chandra, XMM-Newton. and ROSAT provide X-ray luminosities and temperatures that are broadly consistent with this mass threshold. Our optical follow-up procedure also allowed us to assess the purity of the ACT cluster sample. Eighty (one hundred) percent of the 148 GHz candidates with signal-to-noise ratios greater than 5.1 (5.7) are confirmed as massive clusters. The reported sample represents one of the largest SZE-selected sample of massive clusters over all redshifts within a cosmologically-significant survey volume, which will enable cosmological studies as well as future studies on the evolution, morphology, and stellar populations in the most massive clusters in the Universe.
Author
COSMOLOGY; GALACTIC CLUSTERS; LUMINOSITY; STELLAR MASS; SIGNAL TO NOISE RATIOS; ROSAT MISSION; RED SHIFT; STARS
20110023551 NASA Johnson Space Center, Houston, TX, United States
Geochemical Mapping of 4 Vesta Begins
Prettyman, Thomas H.; Feldman, William C.; Forni, Olivier; Joy, Steven P.; Lawrence, David J.; LeCorre, Lucille; Mafi, Joseph N.; McCord, Thomas B.; McCoy, Timothy J.; McSween, Harry Y.; Middlefehldt, David W.; Polanskey, Carol; Rayman, Marc; Raymond, Carol A.; Reddy, Vishnu; Reedy, Robert C.; Russell, Christopher T.; Titus, Timothy N.; Toplis, Mike J.; December 05, 2011; In English; Fall 2011 Meeting of the American Geophysical Union, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): JSC-CN-25371; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023551
By December, the NASA Dawn spacecraft will have descended to a low altitude mapping orbit (LAMO), where the Gamma Ray and Neutron Detector (GRaND) will acquire global mapping data for up to four months. Measurements by GRaND will help answer elusive questions about how Vesta differentiated and the nature of processes that shaped Vesta s surface. The data will be analyzed to determine the abundances of Mg, Si, Fe, K, Th, and H at a spatial resolution of roughly 300 km full-width-at-half-maximum from a 465 km radius orbit. Thermal and fast neutron counting data will be analyzed to determine the neutron macroscopic absorption cross section and average atomic mass, providing constraints on additional elements, such as Ca and Al. GRaND will quantify the elemental composition of coarse spatial units identified by Dawn s Framing Camera (FC) and the Visible & Infrared Spectrometer (VIR). In addition, GRaND will map the mixing ratio of compositional end members selected from the howardite, eucrite and diogenite (HED) meteorites, determine the relative proportions of plagioclase and mafic minerals, and search for compositions that are absent or under-represented in the meteorite collection. While it is generally thought that Vesta s crust on a regional scale should be well-represented by linear mixing of HED whole-rock compositions, there are hints that Vesta may be more diverse than implied by this model. For example, the discovery of K-rich impact glasses in howardites suggests that K-rich rocks may be present on a portion of Vesta s surface, and the analysis of diogenites indicates considerable variability in the magmatic processes that formed them. The chemical composition of materials within Vesta s south polar structure may provide further clues to how it formed. An impact might have exposed mantle and lower crustal materials, which should have a distinctive compositional signature. We present the analysis of data acquired by GRaND from cruise through the descent to LAMO, including GRaND s sensitivity to different elements and geochemical processes.
Author
METEORITIC COMPOSITION; VESTA ASTEROID; NEUTRON CROSS SECTIONS; ABSORPTION CROSS SECTIONS; CHEMICAL COMPOSITION; GEOCHEMISTRY; NEUTRON COUNTERS; MINERALS; MINERALOGY; ABUNDANCE
20110023552 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Constraining the Properties of the Eta Carinae System via 3-D SPH Models of Space-Based Observations: The Absolute Orientation of the Binary Orbit
Madura, Thomas I.; Gull, Theodore R.; Owocki, Stanley P.; Okazaki, Atsuo T.; Russell, Christopher M. P.; Bulletin de la Societe Royale des Sciences de Liege; 2011; vol. Volume 80; pp. 694-69; In English; Original contains black and white illustrations
Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023552
The extremely massive (> 90 Stellar Mass) and luminous (= 5 x 10(exp 6) Stellar Luminosity) star Eta Carinae, with its spectacular bipolar "Homunculus" nebula, comprises one of the most remarkable and intensely observed stellar systems in the Galaxy. However, many of its underlying physical parameters remain unknown. Multiwavelength variations observed to occur every 5.54 years are interpreted as being due to the collision of a massive wind from the primary star with the fast, less dense wind of a hot companion star in a highly elliptical (e approx. 0.9) orbit. Using three-dimensional (3-D) Smoothed Particle Hydrodynamics (SPH) simulations of the binary wind-wind collision, together with radiative transfer codes, we compute synthetic spectral images of [Fe III] emission line structures and compare them to existing Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS) observations. We are thus able, for the first time, to tightly constrain the absolute orientation of the binary orbit on the sky. An orbit with an inclination of approx. 40deg, an argument of periapsis omega approx. 255deg, and a projected orbital axis with a position angle of approx. 312deg east of north provides the best fit to the observations, implying that the orbital axis is closely aligned in 3-D space with the Homunculus symmetry axis, and that the companion star orbits clockwise on the sky relative to the primary.
Author
COMPANION STARS; STELLAR LUMINOSITY; STELLAR MASS; SPACEBORNE TELESCOPES; IMAGING TECHNIQUES; STELLAR SYSTEMS; HYDRODYNAMICS; RADIATIVE TRANSFER
20110023554 Jacobs Technologies Engineering Science Contract Group, Houston, TX, United States
The Impact of Rise of the Andes and Amazon Landscape Evolution on Diversification of Lowland terra-firme Forest Birds
Aleixo, Alexandre; Wilkinson, M. Justin; December 05, 2011; In English; American Geophysical Union Fall Meeting, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): JSC-CN-25221; Copyright; Distribution under U.S. Government purpose rights; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023554
Since the 19th Century, the unmatched biological diversity of Amazonia has stimulated a diverse set of hypotheses accounting for patterns of species diversity and distribution in mega-diverse tropical environments. Unfortunately, the evidence supporting particular hypotheses to date is at best described as ambiguous, and no generalizations have emerged yet, mostly due to the lack of comprehensive comparative phylogeographic studies with thorough trans-Amazonian sampling of lineages. Here we report on spatial and temporal patterns of diversification estimated from mitochondrial gene trees for 31 lineages of birds associated with upland terra-firme forest, the dominant habitat in modern lowland Amazonia. The results confirm the pervasive role of Amazonian rivers as primary barriers separating sister lineages of birds, and a protracted spatio-temporal pattern of diversification, with a gradual reduction of earlier (1st and 2nd) and older (> 2 mya) splits associated with each lineage in an eastward direction. (The easternmost tributaries of the Amazon, the Xingu and Tocantins Rivers, are not associated with any splits older than > 2 mya). For the suboscine passerines, maximum-likelihood estimates of rates of diversification point to an overall constant rate over the past 5 my (up to a significant downturn at 300,000 y ago). This "younging-eastward" pattern may have an abiotic explanation related to landscape evolution. Triggered by a new pulse of Andean uplift, it has been proposed that modern Amazon basin landscapes may have evolved successively eastward, away from the mountain chain, starting approximately 10 mya. This process was likely based on the deposition of vast fluvial sediment masses, known as megafans, that may have extended progressively and in series eastward from Andean sources. This process plausibly explains the progressive extinction of original Pebas wetland of western-central Amazonia by the present fluvial landsurfaces of a more terra-firme type. The youngest landsurfaces thus lie furthest from the mountains. In this scenario major drainages were also reoriented in wholesale fashion away from a northerly orientation generally towards the east and an Atlantic Ocean outlet. The advance of megafans is best seen by the location of axial rivers such as the Orinoco and Mamore which lie against the cratonic margins furthest from the Andes, at the distal ends of major megafan ramparts. More importantly, other major river courses in western-central Amazonia will have been established at progressively younger dates with distance eastward. If this landscape-sequence scenario is accurate, it parallels the progressive younging of the passerine lineages. The bird DNA data appears to confirm strongly the pervasive role of Amazonian rivers--as primary barriers separating sister lineages of birds, and thus probably as facilitaters of bird speciation. We show for the first time that a general spatio-temporal pattern of diversification for terra-firme lineages in the Amazon is associated with rivers ("younging-eastward"), and furthermore parallels a specific scenario of regional drainage evolution.
Author
AMAZON REGION (SOUTH AMERICA); BIOLOGICAL DIVERSITY; BIRDS; DEOXYRIBONUCLEIC ACID; ANDES MOUNTAINS (SOUTH AMERICA); RIVERS; GEOGRAPHIC DISTRIBUTION
20110023555 NASA Johnson Space Center, Houston, TX, United States
Machine Vision for Relative Spacecraft Navigation During Approach to Docking
Chien, Chiun-Hong; Baker, Kenneth; [2011]; In English; Infotech@Aerospace, 19-21 Jun. 2012, Garden Grove, CA, United States; Original contains color illustrations
Contract(s)/Grant(s): WBS 795369.04.01.10
Report No.(s): JSC-CN-25317; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023555
This paper describes a machine vision system for relative spacecraft navigation during the terminal phase of approach to docking that: 1) matches high contrast image features of the target vehicle, as seen by a camera that is bore-sighted to the docking adapter on the chase vehicle, to the corresponding features in a 3d model of the docking adapter on the target vehicle and 2) is robust to on-orbit lighting. An implementation is provided for the case of the Space Shuttle Orbiter docking to the International Space Station (ISS) with quantitative test results using a full scale, medium fidelity mock-up of the ISS docking adapter mounted on a 6-DOF motion platform at the NASA Marshall Spaceflight Center Flight Robotics Laboratory and qualitative test results using recorded video from the Orbiter Docking System Camera (ODSC) during multiple orbiter to ISS docking missions. The Natural Feature Image Registration (NFIR) system consists of two modules: 1) Tracking which tracks the target object from image to image and estimates the position and orientation (pose) of the docking camera relative to the target object and 2) Acquisition which recognizes the target object if it is in the docking camera Field-of-View and provides an approximate pose that is used to initialize tracking. Detected image edges are matched to the 3d model edges whose predicted location, based on the pose estimate and its first time derivative from the previous frame, is closest to the detected edge1 . Mismatches are eliminated using a rigid motion constraint. The remaining 2d image to 3d model matches are used to make a least squares estimate of the change in relative pose from the previous image to the current image. The changes in position and in attitude are used as data for two Kalman filters whose outputs are smoothed estimate of position and velocity plus attitude and attitude rate that are then used to predict the location of the 3d model features in the next image.
Author
COMPUTER VISION; DOCKING; INTERNATIONAL SPACE STATION; SPACE NAVIGATION; FIELD OF VIEW; IMAGE PROCESSING; THREE DIMENSIONAL MODELS; SPACE SHUTTLE ORBITERS; FLIGHT TESTS
20110023556 NASA Johnson Space Center, Houston, TX, United States
Suitport Feasibility - Development and Test of a Suitport and Space Suit for Human Pressurized Space Suit Donning Tests
Boyle, Robert M.; Mitchell, Kathryn; Allton, Charles; Ju, Hsing; [2011]; In English; 42nd International Conference on Environmental Systems, 15-19 Jul. 2012, San Diego, CA, United States
Contract(s)/Grant(s): WBS 794209
Report No.(s): JSC-CN-25318; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023556
The suitport concept has been recently implemented as part of the small pressurized lunar rover (Currently the Space Exploration vehicle, or SEV) and the Multi-Mission Space Exploration Vehicle (MMSEV) concept demonstrator vehicle. Suitport replaces or augments the traditional airlock function of a spacecraft by providing a bulkhead opening, capture mechanism, and sealing system to allow ingress and egress of a spacesuit while the spacesuit remains outside of the pressurized volume of the spacecraft. This presents significant new opportunities to EVA exploration in both microgravity and surface environments. The suitport concept will enable three main improvements in EVA by providing reductions in: pre-EVA time from hours to less than thirty minutes; airlock consumables; contamination returned to the cabin with the EVA crewmember. To date, the first generation suitport has been tested with mockup suits on the rover cabins and pressurized on a bench top engineering unit. The work on the rover cabin has helped define the operational concepts and timelines, and has demonstrated the potential of suitport to save significant amounts of crew time before and after EVAs. The work with the engineering unit has successfully demonstrated the pressurizable seal concept including the ability to seal after the introduction and removal of contamination to the sealing surfaces. Using this experience, a second generation suitport was designed. This second generation suitport has been tested with a spacesuit prototype using the pressure differentials of the spacecraft. This test will be performed using the JSC B32 Chamber B, a human rated vacuum chamber. This test will include human rated suitports, the suitport compatible prototype suit, and chamber modifications. This test will bring these three elements together in the first ever pressurized donning of a rear entry suit through a suitport. This paper presents design of a human rated second generation suitport, modifications to the JSC human rated chamber B to accept a suitport, and a compatible space suit to support pressurized human donning of the pressurized suit through a suitport. Design challenges and solutions and compromises required to develop the system are presented. Initial human testing results are presented.
Author
SPACE SUITS; EXTRAVEHICULAR ACTIVITY; AIR LOCKS; SPACE EXPLORATION; SPACECREWS; VACUUM CHAMBERS; MICROGRAVITY; CONSUMABLES (SPACECRAFT)
20110023558 NASA, Washington, DC United States
Method of performing computational aeroelastic analyses
Silva, Walter A., Inventor; November 15, 2011; In English
Patent Info.: March 27, 2008US-Patent-8,060,350; US-Patent-Appl-SN-12/056,686
No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023558
Computational aeroelastic analyses typically use a mathematical model for the structural modes of a flexible structure and a nonlinear aerodynamic model that can generate a plurality of unsteady aerodynamic responses based on the structural modes for conditions defining an aerodynamic condition of the flexible structure. In the present invention, a linear state-space model is generated using a single execution of the nonlinear aerodynamic model for all of the structural modes where a family of orthogonal functions is used as the inputs. Then, static and dynamic aeroelastic solutions are generated using computational interaction between the mathematical model and the linear state-space model for a plurality of periodic points in time.
Official Gazette of the U.S. Patent and Trademark Office
AERODYNAMIC CHARACTERISTICS; AEROELASTICITY; ANALYSIS (MATHEMATICS); MATHEMATICAL MODELS; NONLINEARITY
Additions to the NASA Aeronautics and Space Database as of 12/22/2011
20110023559 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Lunar Gravity Field Determination Using SELENE Same-Beam Differential VLBI Tracking Data
Goossens, S.; Matsumoto, K.; Liu, Q.; Kikuchi, F.; Sato, K.; Hanada, H.; Ishihara, Y.; Noda, H.; Kawano, N.; Namiki, N.; Iwata, T.; Lemoine, F. G.; Rowlands, D. D.; Harada, Y.; Chen, M.; Journal of Geodesy; December 07, 2010; vol. Volume 85; issue No. 4; pp. 205-22; In English; Original contains black and white illustrations
Contract(s)/Grant(s): JSPS 20244073
Report No.(s): GSFC.JA.5447.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1007/s00190-010-0430-2
A lunar gravity field model up to degree and order 100 in spherical harmonics, named SGM 100i, has been determined from SELENE and historical tracking data, with an emphasis on using same-beam S-band differential VLBI data obtained in the SELENE mission between January 2008 and February 2009. Orbit consistency throughout the entire mission period of SELENE as determined from orbit overlaps for the two sub-satellites of SELENE involved in the VLBI tracking improved consistently from several hundreds of metres to several tens of metres by including differential VLBI data. Through orbits that are better determined, the gravity field model is also improved by including these data. Orbit determination performance for the new model shows improvements over earlier 100th degree and order models, especially for edge-on orbits over the deep far side. Lunar Prospector orbit determination shows an improvement of orbit consistency from I-day predictions for 2-day arcs of 6 m in a total sense, with most improvement in the along and cross-track directions. Data fit for the types and satellites involved is also improved. Formal errors for the lower degrees are smaller, and the new model also shows increased correlations with topography over the far side. The estimated value for the lunar GM for this model equals 4902.80080 +/- 0.0009 cu km/sq s (10 sigma). The lunar degree 2 potential Love number k2 was also estimated, and has a value of 0.0255 +/- 0.0016 (10 sigma as well).
Author
LUNAR GRAVITATION; VERY LONG BASE INTERFEROMETRY; LUNAR PROSPECTOR; ORBIT DETERMINATION; ULTRAHIGH FREQUENCIES; GRAVITATIONAL FIELDS; SUPERHIGH FREQUENCIES; CORRELATION
20110023560 NASA Goddard Space Flight Center, Greenbelt, MD, United States
New Observational Evidence of Flash Mixing on the White Dwarf Cooling Curve
Brown, T. M.; Lanz, T.; Sweigart, A. V.; Cracraft, Misty; Hubeny, Ivan; Landsman, W. B.; [2011]; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NAS5-26555STScI 10815; STScI 11665
Report No.(s): GSFC.JA.5517.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023560
Blue hook stars are a class of subluminous extreme horizontal branch stars that were discovered in UV images of the massive globular clusters w Cen and NGC 2808. These stars occupy a region of the HR diagram that is unexplained by canonical stellar evolution theory. Using new theoretical evolutionary and atmospheric models, we have shown that the blue hook stars are very likely the progeny of stars that undergo extensive internal mixing during a late helium-core flash on the white dwarf cooling curve. This "flash mixing" produces hotter-than-normal EHB stars with atmospheres significantly enhanced in helium and carbon. The larger bolometric correction, combined with the decrease in hydrogen opacity, makes these stars appear sub luminous in the optical and UV. Flash mixing is more likely to occur in stars born with a high helium abundance, due to their lower mass at the main sequence turnoff. For this reason, the phenomenon is more common in those massive globular clusters that show evidence for secondary populations enhanced in helium. However, a high helium abundance does not, by itself, explain the presence of blue hook stars in massive globular clusters. Here, we present new observational evidence for flash mixing, using recent HST observations. These include UV color-magnitude diagrams of six massive globular clusters and far-UV spectroscopy of hot subdwarfs in one of these clusters (NGC 2808).
Author
ATMOSPHERIC MODELS; COLOR-MAGNITUDE DIAGRAM; GLOBULAR CLUSTERS; BLUE STARS; STELLAR EVOLUTION; STELLAR LUMINOSITY; MAIN SEQUENCE STARS; HORIZONTAL BRANCH STARS
20110023561 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Atacama Cosmology Telescope: Detection or Sunyaev-Zel'Dovich Decrement in Groups and Clusters Associated with Luminous Red Galaxies
Hand, Nick; Appel, John William; Battaglia, Nick; Bond, J. Richard; Das, Sudeep; Devlin, Mark J.; Dunkley, Joanna; Dunner, Rolando; Essinger-Hileman, Thomas; Fowler, Joseph W.; Hajian, Amir; Halpern, Mark; Hasselfield, Matthew; Hilton, Matt; Hincks, Adam D.; Hlozek, Renee; Hughes, John P.; Irwin, Kent D.; Klein, Jeff; Kosowsky, Arthur; Lin, Yen-Ting; Marriage, Tobias A.; Marsden, Danica; McLaren, Mike; Wollack, Ed; et al.; August 13, 2010; In English; Original contains black and white illustrations
Contract(s)/Grant(s): DE-AC3-76SF00515NNX08AH30G
Report No.(s): GSFC.JA.5519.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023561
We present a detection of the Sunyaev-Zel'dovich (SZ) decrement associated with the Luminous Red Galaxy (LRG) sample of the Sloan Digital Sky Survey. The SZ data come from 148 GHz maps of the equatorial region made by the Atacama Cosmology Telescope (ACT). The LRG sample is divided by luminosity into four bins, and estimates for the central Sunyaev-Zel'dovich temperature decrement are calculated through a stacking process. We detect and account for a bias of the SZ signal due to weak radio sources. We use numerical simulations to relate the observed decrement to Y(sub 200) and clustering properties to relate the galaxy luminosity bins to mass. We also use a relation between BCG luminosity and cluster mass based on stacked gravitational lensing measurements to estimate the characteristic halo masses. The masses are found to be in the range approx.10(exp 13) - 10(exp 14)/h Stellar Mass, a lower range than has been previously probed.
Author
COSMOLOGY; GRAVITATIONAL LENSES; HALOS; STELLAR MASS; TELESCOPES; EQUATORIAL REGIONS; GALAXIES
20110023562 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Imaging with HST the Time Evolution of Eta Carinae's Colliding Winds
Gull, Theodore R.; Madura, Thomas I.; Groh, Jose H.; Corcoran, Michael F.; October 07, 2011; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NAS5-26555
Report No.(s): GSFC.JA.5520.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023562
We report new HST/STIS observations that map the high-ionization forbidden line emission in the inner arcsecond of Eta Car, the first that fully image the extended wind-wind interaction region of the massive colliding wind binary. These observations were obtained after the 2009.0 periastron at orbital phases 0.084, 0.163, and 0.323 of the 5.54-year spectroscopic cycle. We analyze the variations in brightness and morphology of the emission, and find that blue-shifted emission (-400 to -200 km/s is symmetric and elongated along the northeast-southwest axis, while the red-shifted emission (+ 100 to +200 km/s) is asymmetric and extends to the north-northwest. Comparison to synthetic images generated from a 3-D dynamical model strengthens the 3-D orbital orientation found by Madura et al. (2011), with an inclination i approx. 138deg, argument of periapsis omega approx. 270deg, and an orbital axis that is aligned at the same PA on the sky as the symmetry axis of the Homunculus, 312deg. We discuss the potential that these and future mappings have for constraining the stellar parameters of the companion star and the long-term variability of the system.
Author
COMPANION STARS; BRIGHTNESS; THREE DIMENSIONAL MODELS; STELLAR ORBITS; ORBITAL ELEMENTS; STARS; IMAGING TECHNIQUES; IONIZATION
20110023563 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Correlations in the (Sub)Mil1imeter Background from ACT x BLAST
Hajian, Amir; Battaglia,Nick; Bock, James J.; Bond, J. Richard; Nolta, Michael R.; Sievers, Jon; Wollack, Ed; et al.; January 10, 2011; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NAG5-12785; NAG5-13301; NNG06GI11G; NNX08AH30G; NSF PHY-0114422; NSF PHY-0355328
Report No.(s): GSFC.JA.5521.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023563
We present measurements of the auto- and cross-frequency correlation power spectra of the cosmic (sub)millimeter background at: 250, 350, and 500 microns (1200, 860, and 600 GHz) from observations made with the Balloon-borne Large Aperture Submillimeter Telescope, BLAST; and at 1380 and 2030 microns (218 and 148 GHz) from observations made with the Atacama Cosmology Telescope, ACT. The overlapping observations cover 8.6 deg(sup 2) in an area relatively free of Galactic dust near the south ecliptic pole (SEP). The ACT bands are sensitive to radiation from the CMB, the Sunyaev-Zel'dovich (SZ) effect from galaxy clusters, and to emission by radio and dusty star-forming galaxies (DSFGs), while the dominant contribution to the BLAST bands is from DSFGs. We confirm and extend the BLAST analysis of clustering with an independent pipeline, and also detect correlations between the ACT and BLAST maps at over 25(sigma) significance, which we interpret as a detection of the DSFGs in the ACT maps. In addition to a Poisson component in the cross-frequency power spectra, we detect a clustered signal at 4(sigma), and using a model for the DSFG evolution and number counts, we successfully fit all our spectra with a linear clustering model and a bias that depends only on red shift and not on scale. Finally, the data are compared to, and generally agree with, phenomenological models for the DSFG population. This study represents a first of its kind, and demonstrates the constraining power of the cross-frequency correlation technique to constrain models for the DSFGs. Similar analyses with more data will impose tight constraints 011 future models.
Author
COSMOLOGY; COSMIC MICROWAVE BACKGROUND RADIATION; GALACTIC CLUSTERS; SUBMILLIMETER WAVES; POWER SPECTRA; DUST; CROSS CORRELATION; RED SHIFT; RADIO STARS
20110023564 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Constraints on Determining the Eruption Style and Composition of Terrestrial Lavas from Space
Wright, Robert; Glaze, Lori; Baloga, Stephen M.; Geology; October 10, 2011; vol. Volume 39; issue No. 12; pp. 1127-113; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): NNX08AG03G; NNX10AT65G; NNZ10AP63GWBS 811073.02.01.04.44
Report No.(s): GSFC.JA.5524.2011; Copyright; Availability: Other Sources
Avail Online: http://dx.doi.org/10.1130/G32341.1
The surface temperatures of active lavas relate to cooling rates, chemistry, and eruption style. We analyzed 61 hyperspectral satellite images acquired by the National Aeronautics and Space Administration s Earth Observing-1 (EO-1) Hyperion imaging spectrometer to document the surface temperature distributions of active lavas erupted at 13 volcanoes. Images were selected to encompass the range of common lava eruption styles, specifically, lava fountains, flows, lakes, and domes. Our results reveal temperature distributions for terrestrial lavas that correlate with composition (i.e., a statistically significant difference in the highest temperatures retrieved for mafic lavas and intermediate and felsic lavas) and eruption style. Maximum temperatures observed for mafi c lavas are approx.200 C higher than for intermediate and felsic lavas. All eruption styles exhibit a low-temperature mode at approx.300 C; lava fountains and 'a' a flows also exhibit a higher-temperature mode at approx.700 C. The observed differences between the temperatures are consistent with the contrasting rates at which the lava surfaces are thermally renewed. Eruption styles that allow persistent and pervasive thermal renewal of the lava surface (e.g., fractured crusts on channel-fed 'a' a flows) exhibit a bimodal temperature distribution; eruption styles that do not (e.g., the continuous skin of pahoehoe lavas) exhibit a single mode. We conclude that insights into composition and eruption style can only be gained remotely by analyzing a large spatio-temporal sample of data. This has implications for determining composition and eruption style at the Jovian moon Io, for which no in situ validation is available.
Author
LAVA; FLUID FLOW; CRUSTS; SATELLITE IMAGERY; SURFACE TEMPERATURE; VOLCANIC ERUPTIONS; TEMPERATURE DISTRIBUTION; MINERALOGY
20110023565 NASA Goddard Space Flight Center, Greenbelt, MD, United States
The Atacama Cosmology Telescope: A Measurement of the Primordial Power Spectrum
Hlozek, Renee; Dunkley, Joanna; Addison, Graeme; Appel, John William; Bond, J. Richard; Carvalho, C. Sofia; Das, Sudeep; Devlin, Mark J.; Duenner, Rolando; Essinger-Hileman, Thomas; Fowler, Joseph W.; Gallardo, Patricio; Hajian, Amir; Halpern, Mark; Hasselfield, Matthew; Hilton, Matt; Hincks, Adam D.; Hughes, John P.; Irwin, Kent D.; Klein, Jeff; Kosowsky, Arthur; Marriage, Tobias A.; Marsden, Danica; Menanteau, Felipe; Wollack, Ed; May 27, 2011; In English; Original contains black and white illustrations
Contract(s)/Grant(s): DE-AC3-76SF0051NNX08AH30G; NSF AST-0408698; NSF PHY-0355328; NSF AST-0707731; NSF PIRE-0507768; ERC 259505
Report No.(s): GSFC.JA.5511.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023565
We present constraints on the primordial power spectrum of adiabatic fluctuations using data from the 2008 Southern Survey of the Atacama Cosmology Telescope (ACT). The angular resolution of ACT provides sensitivity to scales beyond l = 1000 for resolution of multiple peaks in the primordial temperature power spectrum, which enables us to probe the primordial power spectrum of adiabatic scalar perturbations with wavenumbers up to k approx. = 0.2 Mp/c. We find no evidence for deviation from power-law fluctuations over two decades in scale. Matter fluctuations inferred from the primordial temperature power spectrum evolve over cosmic time and can be used to predict the matter power spectrum at late times; we illustrate the overlap of the matter power inferred from CMB measurements (which probe the power spectrum in thc linear regime) with existing probes of galaxy clustering, cluster abundances and weak lensing constraints on the primordial power. This highlights the range of scales probed by current measurement.s of the matter power spectrum.
Author
ANGULAR RESOLUTION; GALACTIC CLUSTERS; TELESCOPES; PERTURBATION
Additions to the NASA Aeronautics and Space Database as of 12/23/2011
20110023570 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Toward a Framework for Systematic Error Modeling of NASA Spaceborne Radar with NOAA/NSSL Ground Radar-Based National Mosaic QPE
Kirstettier, Pierre-Emmanual; Honh, Y.; Gourley, J. J.; Chen, S.; Flamig, Z.; Zhang, J.; Howard, K.; Schwaller, M.; Petersen, W.; Amitai, E.; October 14, 2011; In English; Original contains black and white illustrations
Report No.(s): GSFC.JA.5526.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023570
Characterization of the error associated to satellite rainfall estimates is a necessary component of deterministic and probabilistic frameworks involving space-born passive and active microwave measurement") for applications ranging from water budget studies to forecasting natural hazards related to extreme rainfall events. We focus here on the error structure of NASA's Tropical Rainfall Measurement Mission (TRMM) Precipitation Radar (PR) quantitative precipitation estimation (QPE) at ground. The problem is addressed by comparison of PR QPEs with reference values derived from ground-based measurements using NOAA/NSSL ground radar-based National Mosaic and QPE system (NMQ/Q2). A preliminary investigation of this subject has been carried out at the PR estimation scale (instantaneous and 5 km) using a three-month data sample in the southern part of US. The primary contribution of this study is the presentation of the detailed steps required to derive trustworthy reference rainfall dataset from Q2 at the PR pixel resolution. It relics on a bias correction and a radar quality index, both of which provide a basis to filter out the less trustworthy Q2 values. Several aspects of PR errors arc revealed and quantified including sensitivity to the processing steps with the reference rainfall, comparisons of rainfall detectability and rainfall rate distributions, spatial representativeness of error, and separation of systematic biases and random errors. The methodology and framework developed herein applies more generally to rainfall rate estimates from other sensors onboard low-earth orbiting satellites such as microwave imagers and dual-wavelength radars such as with the Global Precipitation Measurement (GPM) mission.
Author
SATELLITE-BORNE INSTRUMENTS; METEOROLOGICAL RADAR; EARTH ORBITS; MICROWAVES; PRECIPITATION (METEOROLOGY); PRECIPITATION MEASUREMENT; RANDOM ERRORS; SYSTEMATIC ERRORS; TRMM SATELLITE; RAIN
20110023571 NASA Johnson Space Center, Houston, TX, United States
Project KEWL: Kinect Engineering With Learning
Norris, Jeff; Goza, Sharon; Shores, David; [2011]; In English; Global Exploration Conference, 22-24 May 2012, Washington, DC, United States
Report No.(s): JSC-CN-25354; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023571
Project KEWL is a joint project between NASA/JPL and NASA/JSC to stimulate interest of children in Science, Technology, Engineering and Math (STEM) and bring the NASA space exploration experience to the classroom, museum and ultimately the living room. Using the Kinect game controller KEWL allows children to engage in NASA s missions in a fundamentally new way. KEWL allows children to experiment with gravity on Mars and the Moon; navigate through the International Space Station; fix a torn solar array on the ISS; drive a robot on Mars; visit an Asteroid; learn about the differences in gravity on different planets and control Robonaut 2 using their body as the input device. Project KEWL complements NASA s outreach investments in television, mobile platforms and the web by engaging the public through the rapidly expanding medium of console gaming. In 2008, 97% of teenagers played video games and 86% played on a home gaming console. (source: http://pewresearch.org/pubs/953/) As of March 2011, there have been more than 10 million Kinects sold. (source: http://www.itproportal.com/2011/03/10/kinect-record-breaking -sales-figures-top-10-million/) Project KEWL interacts with children on a platform on which they spend much of their time and teaches them information about NASA while they are having fun. Project KEWL progressed from completely custom C++ code written in house to using a commercial game engine. The art work and 3D geometry models come from existing engineering work or are created by the KEWL development team. Six different KEWL applications have been demonstrated at nine different venues including schools, museums, conferences, and NASA outreach events. These demonstrations have allowed the developers the chance to interact with players and observe the gameplay mechanics in action. The lessons learned were then incorporated into the subsequent versions of the applications.
Author
C++ (PROGRAMMING LANGUAGE); SPACE EXPLORATION; TELEVISION SYSTEMS; INTERNATIONAL SPACE STATION; LESSONS LEARNED; CONTROLLERS; SOLAR ARRAYS; THREE DIMENSIONAL MODELS
Additions to the NASA Aeronautics and Space Database as of 12/26/2011
20110023616 NASA Goddard Space Flight Center, Greenbelt, MD, United States
PDS4: Developing the Next Generation Planetary Data System
Crichton, D.; Beebe, R.; Hughes, S.; Stein, T.; Grayzeck, E.; October 02, 2011; In English; EPSC-DPS Joint Meeting 2011, 2-7 Oct. 2011, Nantes, France
Report No.(s): GSFC.OVPR.5331.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023616
The Planetary Data System (PDS) is in the midst of a major upgrade to its system. This upgrade is a critical modernization of the PDS as it prepares to support the future needs of both the mission and scientific community. It entails improvements to the software system and the data standards, capitalizing on newer, data system approaches. The upgrade is important not only for the purpose of capturing results from NASA planetary science missions, but also for improving standards and interoperability among international planetary science data archives. As the demands of the missions and science community increase, PDS is positioning itself to evolve and meet those demands.
Author
DATA SYSTEMS; SPACE MISSIONS; INTEROPERABILITY; COMPUTER PROGRAMS; SOLAR SYSTEM
20110023617 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Atmospheric Blocking and Atlantic Multi-Decadal Ocean Variability
Haekkinen, Sirpa; Rhines, Peter B.; Worthlen, Denise L.; July 11, 2011; In English; International Science Meeting: Past Present and Future CHange in the Atlantic Meridional Overturning Circulation, 12-15 Jul. 2011, Bristol, United Kingdom; Original contains color illustrations
Report No.(s): GSFC.OVPR.5346.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023617
Based on the 20th century atmospheric reanalysis, winters with more frequent blocking, in a band of blocked latitudes from Greenland to Western Europe, are found to persist over several decades and correspond to a warm North Atlantic Ocean, in-phase with Atlantic multi-decadal ocean variability. Atmospheric blocking over the northern North Atlantic, which involves isolation of large regions of air from the westerly circulation for 5 days or more, influences fundamentally the ocean circulation and upper ocean properties by impacting wind patterns. Winters with clusters of more frequent blocking between Greenland and western Europe correspond to a warmer, more saline subpolar ocean. The correspondence between blocked westerly winds and warm ocean holds in recent decadal episodes (especially, 1996-2010). It also describes much longer-timescale Atlantic multidecadal ocean variability (AMV), including the extreme, pre-greenhouse-gas, northern warming of the 1930s-1960s. The space-time structure of the wind forcing associated with a blocked regime leads to weaker ocean gyres and weaker heat-exchange, both of which contribute to the warm phase of AMV.
Author
AIR MASSES; ATMOSPHERIC CIRCULATION; OCEAN CURRENTS; AIR CURRENTS; BLOCKING; GREENHOUSE EFFECT; HEAT TRANSFER; SEA SURFACE TEMPERATURE; PRESSURE DISTRIBUTION; PERIODIC VARIATIONS; OSCILLATIONS; CLIMATE
20110023618 NASA Goddard Space Flight Center, Greenbelt, MD, United States
GSFC Supplier Surveillance
Kelly, Michael P.; October 19, 2011; In English; Original contains color illustrations
Report No.(s): GSFC.OVPR.5415.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023618
Topics covered include: Develop Program/Project Quality Assurance Surveillance Plans The work activities performed by the developer and/or his suppliers are subject to evaluation and audit by government-designated representatives. CSO supports project by selecting on-site supplier representative s by one of several methods: (1) a Defense Contract Management Agency (DCMA) person via a Letter Of Delegation (LOD), (2) an independent assurance contractor (IAC) via a contract Audits, Assessments, and Assurance (A3) Contract Code 300 Mission Assurance Support Contract (MASC)
Author
SUPPLYING; SURVEILLANCE; QUALITY CONTROL
20110023619 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Failure Assessment Diagram for Titanium Brazed Joints
Flom, Yury; Jones, Justin S.; Powell, Mollie M.; Puckett, David F.; October 2011; In English; Original contains color illustrations
Report No.(s): NASA/TM-2011-215882; GSFC.TM.5341.2011; No Copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023619
The interaction equation was used to predict failure in Ti-4V-6Al joints brazed with Al 1100 filler metal. The joints used in this study were geometrically similar to the joints in the brazed beryllium metering structure considered for the ATLAS telescope. This study confirmed that the interaction equation R(sub sigma) + R(sub Tau) = 1, where R(sub sigma) and R(sub Tau)are normal and shear stress ratios, can be used as conservative lower bound estimate of the failure criterion in ATLAS brazed joints as well as for construction of the Failure Assessment Diagram (FAD).
Author
BRAZING; SOLDERED JOINTS; TITANIUM; STRUCTURAL FAILURE; FAILURE ANALYSIS
20110023620 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Requirements for an Advanced Ocean Radiometer
Meister, Gerhard; McClain, Charles R.; Ahmad, Ziauddin; Bailey, Sean W.; Barnes, Robert A.; Brown, Steven; Eplee, Robert E.; Franz, Bryan; Holmes, Alan; Monosmith, W. Bryan; Patt, Frederick S.; Stumpf, Richard P.; Turpie, Kevin R.; Werdell, P. Jeremy; October 2011; In English; Original contains color illustrations
Report No.(s): NASA/TM-2011-215883; GSFC.TM.5375.2011; Copyright; Distribution as joint owner in the copyright; Availability: CASI
Avail Online: http://hdl.handle.net/2060/20110023620
This document suggests requirements for an advanced ocean radiometer, such as e.g. the ACE (Aerosol/Cloud/Ecosystem) ocean radiometer. The ACE ocean biology mission objectives have been defined in the ACE Ocean Biology white paper. The general requirements presented therein were chosen as the basis for the requirements provided in this document, which have been transformed into specific, testable requirements. The overall accuracy goal for the advanced ocean radiometer is that the total radiometric uncertainties are 0.5% or smaller for all bands. Specific mission requirements of SeaWiFS, MODIS, and VIIRS were often used as a model for the requirements presented here, which are in most cases more demanding than the heritage requirements. Experience with on-orbit performance and calibration (from SeaWiFS and MODIS) and prelaunch testing (from SeaWiFS, MODIS, and VIIRS) were important considerations when formulating the requirements. This document describes requirements in terms of the science data products, with a focus on qualities that can be verified by prelaunch radiometric characterization. It is expected that a more comprehensive requirements document will be developed during mission formulation
Author
OCEANS; MODIS (RADIOMETRY); SEA-VIEWING WIDE FIELD-OF-VIEW SENSOR; CALIBRATING; PERFORMANCE TESTS; IMAGING SPECTROMETERS; RADIOMETERS
20110023625 NASA Johnson Space Center, Houston, TX, United States
Macro vs. Micro: Relating the Spectral Properties of Vesta and the HED Meteorite
Ammannito, E.; Coradini, A.; DeSanctis, M. C.; Filacchione, G.; Fonte, S.; Magni, G.; Capaccioni, F.; Capria, M. T.; Tosi, F.; Blewett, D. T.; Combe, J. P.; Farina, M.; Mittlefehldt, D. W.; Palomba, E.; Pieters, C. M.; Sunshine, J.; Titus, T. N.; Toplis, M. J.; Russell, C. T.; Raymond, C. A.; McSween, H. Y., Jr.; December 05, 2011; In English; Fall 2011 Meeting of the American Geophysical Union, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): JSC-CN-25372; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023625
We present the main results obtained comparing the visible-near infrared (VIS-NIR) spectra Vesta s surface with howardites, eucrites, diogenites (HED). HEDs are commonly associated with Vesta s composition based on spectral similarities. Because of such association, much effort is being made to merge the information from HEDs as well as Vestoids - with that from Vesta to characterize the lithologic diversity of the surface of this asteroid and to infer clues regarding its thermal history. However, while the HEDs are a class of meteorites well studied in the laboratory, the only spectral data available for Vesta until now were telescopic observations which are limited in terms of observation conditions, spatial resolution and Signal to Noise Ratio. The Dawn spacecraft, orbiting around Vesta since July 2011, is performing detailed observations of this body and thus improving our knowledge of its properties. Dawn s scientific payload includes an imaging spectrometer, VIR-MS, sensitive to the VIS-NIR spectral range. VIR-MS began acquiring spectra during the approach phase started in May 2011 and will continue its observations through July 2012 when the spacecraft will depart Vesta to travel to Ceres. The VIR-MS spatial resolution depends upon the mission phase (approach, survey, high altitude, low altitude). However, spectra acquired by VIR-MS have already exceeded the spatial resolution of ground-based telescopic observations, with resolution in the approach phase ranging from 2.5 up to 0.8 km/pixel. Moreover, the observations are uniformly distributed in latitude and longitude allowing us to have a global view of Vesta s crust spectral properties. Using the information provided by VIR spectra, we studied the distribution of the spectral heterogeneities on the surface and we used our findings to perform a comparison with HEDs spectra in the VIS-NIR spectral range searching for analogies and/or incompatibilities. In our analysis, we focused on a method to compare the results obtained at microscopic scale on HEDs samples and the one obtained at macroscopic scale on the surface of Vesta. Finally, we discuss our results in the context of vestan thermal history. The intent of this study is to improve our understanding of the connection between Vesta and the HED samples, which is one of the primary Dawn scientific objectives. This work is supported by an Italian Space Agency (ASI) grant and by NASA through the Dawn project and a Dawn at Vesta Participating Scientist grant.
Author
VESTA ASTEROID; METEORITIC COMPOSITION; NEAR INFRARED RADIATION; EMISSION SPECTRA; IMAGING SPECTROMETERS; METEORITES; SIGNAL TO NOISE RATIOS; LITHOLOGY
20110023626 NASA Johnson Space Center, Houston, TX, United States
4 Vesta in Color: High Resolution Mapping from Dawn Framing Camera Images
Reddy, V.; LeCorre, L.; Nathues, A.; Sierks, H.; Christensen, U.; Hoffmann, M.; Schroeder, S. E.; Vincent, J. B.; McSween, H. Y.; Denevi, B. W.; Li, J.-Y.; Pieters, C. M.; Gaffey, M.; Mittlefehldt, D.; Buratti, B.; Hicks, M.; McCord, T.; Combe, J.-P.; DeSantis, M. C.; Russell, C. T.; Raymond, C. A.; Marques, P. Gutierrez; Maue, T.; Hall, I.; December 05, 2011; In English; Fall 2011 Meeting ofthe American Geophysical Union, 5-9 Dec. 2011, San Francisco, CA, United States
Report No.(s): JSC-CN-25373; Copyright; Distribution as joint owner in the copyright; Availability: CASI; Abstract Only
Avail Online: http://hdl.handle.net/2060/20110023626
Rotational surface variations on asteroid 4 Vesta have been known from ground-based and HST observations, and they have been interpreted as evidence of compositional diversity. NASA s Dawn mission entered orbit around Vesta on July 16, 2011 for a year-long global characterization. The framing cameras (FC) onboard the Dawn spacecraft will image the asteroid in one clear (broad) and seven narrow band filters covering the wavelength range be
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