http://www.nasa.gov/multimedia/guidelines/index.html http://www.nasa.gov/multimedia/guidelines/index.html There are some restrictions but they're all very sens

http://www.nasa.gov/multimedia/guidelines/index.html http://www.nasa.gov/multimedia/guidelines/index.html There are some restrictions but they're all very sensible, like forbidding the use of official logos to imply endorsement, etc.