via ScienceDaily, the Cassini space probe is showing evidence that Saturn's largest moon Titan may have an underground ocean of water and ammonia.
""With its organic dunes, lakes, channels and mountains, Titan has one of the most varied, active and Earth-like surfaces in the solar system," said Ralph Lorenz, lead author of the paper and Cassini radar scientist at the Johns Hopkins Applied Physics Laboratory in Laurel, Md., "Now we see changes in the way Titan rotates, giving us a window into Titan's interior beneath the surface."
Members of the mission's science team used Cassini's Synthetic Aperture Radar to collect imaging data during 19 separate passes over Titan between October 2005 and May 2007. The radar can see through Titan's dense, methane-rich atmospheric haze, detailing never-before-seen surface features and establishing their locations on the moon's surface."
The scientists compared early radar maps of Titan's surface from the latest ones gathered, and a number of unique surface features identified in the frist maps had shifted significantly, up to 19 miles in some cases. Such an extenisve displacement is difficult to explain unless the surface is separated from the moon's core, floating on an ocean of water. It is believed the ocean may lie as deep as 62 miles under the surface. Cassini will make another flyby on March 25, using its instruments to both examine the atmosphere and the moon's southeastern surface quadrant.