These drawings depict explanations for the source of intense heat that has been measured coming from Enceladus' south polar region. These models predict that water could exist in a deep layer as an ocean or sea and also near the surface.

Cassini scientists infer that the temperature of the ice in the south polar region must be close to its melting point (shown in red). A layer of liquid water (dark blue) might exist between the ice and the silicate core (brown), allowing the ice to deform independent of the rock, providing even more mechanical energy and more flexing of the icy shell for extreme tidal heating.

Tidal heating could also cause friction in faults near the surface, leading to pockets of partially melted ice.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm.