Aerospace Research and Development

Goddard Space Flight Center

The purpose of TRACE is to study the Sun's magnetic fields in connection with the heating of its corona.

Chances are that the latest spectacular, headline-stealing discovery in space, physics, or astronomy is
connected to research underway at the Goddard Space Flight Center. This center was established in
1959, becoming NASA's first major scientific laboratory dedicated entirely to space exploration.

Goddard is situated in Greenbelt, Maryland, taking on duties in space science, earth science, and technology development. The center is involved in implementing suborbital programs as well, using aircraft, balloons, and sounding rockets. This function is located at the Wallops Flight Facility on Wallops Island, Virginia.

The ongoing goal of NASA's Earth Science Enterprise is to integrate data to better study the Earth as a system. There are basic questions at the heart of such an investigation. What makes the Earth habitable? Why here, and on no other planet in our solar system do we find highly diversified life? One obvious reason is that Earth's climate system constitutes a thermostat unique in our solar system.

But the Earth is a dynamic system, with interrelated elements that feed into complex layers of hydrosphere, physical earth, and atmosphere, along with the biosphere. Goddard scientists are attempting to put the pieces of a global puzzle together to develop a conceptual Earth system model, but those components are highly interactive. NASA's Earth Observing System (EOS)--a series of science satellites--offers a way to decipher and scrutinize all the key interactions of the Earth's climate system. Some 25 launches to place 30 satellites into low Earth orbits by 2003 are now on the books.

Soon to join the recently orbited Landsat 7, are other major Earth science missions, including Terra, the first EOS morning satellite (AM-1), along with the first EOS afternoon satellite (PM-1), the Ice, Cloud and Land Elevation Satellite (ICEsat-1), and the atmospheric chemistry mission (CHEM-1).

Goddard scientists have already begun to watch the Earth's climate unfold. Launched in 1997, the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) has yielded new insights into the impact of El Niño-related events, specifically on ocean life, such as phytoplankton blooms. SeaWiFS also eyed floods in China, Gobi and Sahara Desert dust storms, fires in Mexico, and the spiraling fury of hurricanes Bonnie and Danielle.

Also recently lofted was the Tropical Rainfall Measuring Mission (TRMM). This jointly U.S.- and Japanese-built satellite is measuring tropical and subtropical rainfall, lightning variability and distribution, and solar absorbed and Earth emitted radiation. TRMM is intended to enhance our knowledge of the vertical distribution of heating in the atmosphere and improve basic understanding of worldwide atmospheric circulation.

While taking the pulse of Earth is crucial for personal and planetary well-being, a sense of wonderment about the surrounding universe also occupies many of Goddard's scientists and engineers. Goddard is readying for a 2000 launch of the Microwave Anisotropy Probe (MAP), which will be assigned the task of measuring temperature variations in microwave radiation from the cosmological Big Bang. A technology program is underway to fashion Constellation-X, a mission to study powerful objects and events, like supermassive black holes and exploding stars. Goddard is active in the Gamma Ray Large Area Space Telescope (GLAST), to be launched in 2005 to observe the most violent events in the universe with unprecedented detail.

Landsat 7 represents an unprecedented program to check the health of Earth.

The physical processes that link the Sun and the Earth are being evaluated by Goddard spacecraft. First results from the Goddard-managed Advanced Composition Explorer (ACE) have challenged the current understanding of the acceleration of particles caused by explosions on the Sun. Similarly, the Transition Region and Coronal Explorer (TRACE) relayed stunning observations of activity in the solar atmosphere. Powerful events on the Sun, such as flares, can trigger communication and power system failures on Earth.

The quest to peer even deeper into the universe is under the direction of Goddard through its Next-Generation Space Telescope (NGST) project. NGST represents challenges on numerous engineering fronts, from lightweight structures to multi-segmented, deployable mirrors. The mega-powerful NGST could be launched in 2007, built to see objects 400 times fainter than those currently studied with larger ground-based infrared telescopes or other spaceborne counterparts. Moreover, NGST must study objects with the image sharpness achieved by the Hubble Space Telescope.

From the immensity of the universe down to the size of a nano-satellite, Goddard engineers have begun a technology development effort to build disc-shaped spacecraft, weighing less than 22 pounds. A mere 12 inches wide, and just 4 inches thick, nano-satellites are viewed as a method to revolutionize the scientific investigations of key physical processes, in both the space science and Earth science arenas.

Goddard planners envision tens to hundreds of nano-satellites dispatched in space, flying in formation in order to make simultaneous measurements of an area of the sky. This approach would provide scientists more precise data than a single satellite taking a single measurement. For the first time, simultaneous measurements in both space and time will be resolved.

Whether developing missions that rewrite the text books to better understand our own planet or unlock the mysteries of the universe, Goddard is positioned to enter the 21^st century on the cutting edge.