Saturn's Infrared Glow
Credit: VIMS Team, U. Arizona, ESA, NASA
Explanation: Known for its bright ring system and many moons, gas giant Saturn looks strange and unfamiliar in this false-color view from the Cassini spacecraft. In fact, in this Visual and Infrared Mapping Spectrometer (VIMS) mosaic the famous rings are almost invisible, seen edge-on cutting across picture center. The most striking contrast in the image is along the terminator or boundary between night and day. To the right (day side) blue-green hues are visible sunlight reflected from Saturn's cloud tops. But on the left (night side) in the absence of sunlight, the lantern-like glow of infrared radiation from the planet's warm interior silhouettes features at Saturn's deeper cloud levels.
APOD presents: Astronomy Pictures of the Year for 2007