Scientific data shared via NASA data repositories currently falls into three categorizations for licenses:

1. The data has a license provided with it or is labeled with its license. The data or data collection may be labeled with a license as part of the metadata. The licenses and terms of usage may be provided on the website, in the documentation of the data, or via other methods.
2. Unless the data file is marked with a restrictive notice or license, data that is provided from a NASA-led mission including observations, engineering, calibration, and auxiliary data are licensed as Creative Commons Zero. There are no restrictions on the usage of these data.
3. For all other data, the data are provided as is and NASA makes no warranty whatsoever or representations regarding usage. NASA may not be the original source of data and thus users are encouraged to validate the source and associated usage rights of the data.

Data providers may contact the repository regarding licensing problems and revisions will be reviewed for possible licensing changes.  

Regardless of the license, users are encouraged to cite the original source of the data and the usage of the repository when appropriate.

For other material on NASA websites beyond the scientific data, please see the NASA media usage guidance.