Photos: Could life exist beneath Saturn's moon Enceladus?

Could life exist beneath Enceladus? A recent flyby of Saturn's icy moon has bolstered this fascinating idea. Two years ago, images from the robotic Cassini spacecraft orbiting Saturn led astronomers to the undeniable conclusion that Saturn's moon Enceladus was spewing fountains of gas and ice crystals through cracks in its surface dubbed tiger stripes. Last month, Cassini dove through some of these plumes and determined that they contained water vapor laced with small amounts of methane as well as simple and complex organic molecules. Surprisingly, the plumes of Enceladus appear similar in make-up to many comets. What's more, the temperature and density of the plumes indicate they might have originated from a warmer source -- possibly a liquid source -- beneath the surface. A liquid water sea containing organic molecules is a good place to look for life.

http://photojournal.jpl.nasa.gov/catalog/PIA10352

Pictured above is a vertically exaggerated close-up of some long, venting tiger stripes. The computer composite was generated from images and shadows taken during the recent Cassini flyby. Nine more flybys of Enceladus by Cassini are planned.

The plumes of water and other ice vapors jetting from the surface of Enceladus are one of the most exciting astronomical discoveries of the 21st century. These plumes originate from long linear fractures near the south pole of Enceladus. New topographic maps give us a fresh unprecedented look at this geologically young and active region. This perspective view shows several of these "tiger stripes" from which the plumes are venting. The stripes themselves consist of deep grooves flanked by two elevated ridges. The south polar terrains generally are also heavily fractured and deformed.

These new topographic maps, constructed from stereo and shape-from-shading techniques by Dr. Paul Schenk (http://www.lpi.usra.edu/lpi/schenk/) at the Lunar and Planetary Institute, show that the stripes do not have a lot of relief. The flanking ridges are typically 75 to 200 meters high while the grooves in between the ridges are 150 to 300 meters deep. Intensely deformed ridges along the edge of the south polar terrains (lower right) have relief of up to 1 kilometer or so. Vertical relief has been exaggerated by a factor of 20 in this view to aid interpretation.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The 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.