Probably a satellite used for astronomy observations.
http://wiki.answers.com/Q/What_is_an_astronomy_satellit...
The x-ray wavelengths that occur naturally in the cosmos are generally longer and less penetrating than the x-rays we generate artificially for diagnostic and inspection purposes. Because they are of a longer wavelength, they don't penetrat...
http://answers.yahoo.com/question/index?qid=20080925124...
Because Earth's atmosphere and magnetosphere keeps x-rays and other high energy light rays from getting to the surface.
http://answers.yahoo.com/question/index?qid=20090923202...
These moons orbit close to planetary rings, and with their gravity, prevent the rings from dispersing, like shepherds.
http://wiki.answers.com/Q/Why_do_astronomers_call_certa...
If you are wondering this, good question! Right now, amateur astronomers are discovering and tracking asteroids, comets, discovering supernovae (both inter-galactic and extra-galactic), and discovering possible new planets in our own sola...
http://ottawa-rasc.ca/articles/earl_mike/Satellite_Trac...
1. a satellite equipped with a telescope to observe infrared radiation
http://www.audioenglish.net/dictionary/astronomy_satell...
A satellite orbits another body. The moon is a natural satellite of the earth. For awhile, LCROSS was a satellite of the moon (until we smashed it into the lunar surface).
http://wiki.answers.com/Q/What_is_a_satellite_in_astron...