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Earth as seen from the International Space Station (ISS)

NASA Thesaurus

Cite the NASA Thesaurus | Access the NASA Thesaurus

The NASA Thesaurus contains the authorized NASA subject terms used to index and retrieve materials in the STI Repository launch . The scope of this controlled vocabulary includes not only aerospace engineering, but all supporting areas of engineering and physics, the natural space sciences (astronomy, astrophysics, and planetary science), Earth sciences, and the biological sciences. The NASA Thesaurus contains over 18,400 subject terms, 4,300 definitions, and more than 4,500 USE cross references.

If you have any questions or would like to discuss your usage of the thesaurus with the STI Program Office, contact the STI Information Desk .

Cite the NASA Thesaurus

Please cite the NASA STI Program in your work if you incorporate/use the NASA Thesaurus. You may copy and paste any one of the standard citations below (be sure to change ‘SKOS’ to the file format you used):


NASA STI Program. (2012). NASA thesaurus [Data file]. Retrieved from launch


NASA STI Program. NASA Thesaurus. Washington, DC: National Aeronautics and Space Administration, 2012. SKOS.


NASA STI Program. NASA Thesaurus. SKOS. Washington, DC: National Aeronautics and Space Administration, 2012. Choose the file format you would like to use:

Access the NASA Thesaurus

PDF Version

Access the PDF version (updated January 2012) using the links below:

NASA Thesaurus Data File

The NASA Thesaurus Data File contains all valid terms and hierarchical relationships, USE references, and related terms in machine-readable form. The Data File is available in the following formats: RDF/SKOS, RDF/OWL, ZThes-1.0, and CSV/TXT.

The full NASA Thesaurus data files can be downloaded by clicking on a link below.