09 July 2007
Credit: NASA/JPL/University of Arizona/Ames/Space Science Institute
Data acquired recently by the Saturn-bound Cassini spacecraft demonstrated that Hyperion, Saturn's icy peculiar moon, has patches of a thin coat of organic dust, deposited somehow on the bottoms of some craters.
The organic substances are reddish-black in color. The above color map reveals the composition of a portion of Hyperion's surface, examined applying Cassini's Visual and Infrared Mapping Spectrometer. The new composition map is superimposed on a previously-published image of Hyperion, obtained with Cassini's Imaging Science Subsystem. Blue represents the highest exposure of frozen water. Red denotes carbon dioxide ice (dry ice). Magenta highlights regions of water and carbon dioxide. Yellow is carbon dioxide mix with an unidentified material.
Hyperion (about 300 km across) is the eighth largest of Saturn's large system of moons. It has a rugged surface, featuring craters and landslides. Hyperion was discovered in 1848 by Bond and Lassell. Despite its relatively large size, Hyperion is irregular in shape. Cassini's superb views of this enigmatic moon revealed it resembles a gigantic sponge. Hyperion tumbles chaotically in space, and orbits Saturn every 21 days. Its average distance from Saturn is approximately 1,480,000 km.
Further Reading
Saturn's Moons
http://saturn.jpl.nasa.gov/science/moons/index.cfm
The Cassini-Huygens Mission
http://saturn.jpl.nasa.gov/home/index.cfm
JPL's PIA07761
http://www.nasa.gov/mission_pages/cassini/multimedia/pia07761.html
Aymen Mohamed Ibrahem
Senior Astronomy Specialist