The terminator encroaches upon Penelope, one of the largest craters on Saturn's moon Tethys. Two other large craters, Polyphemus and Phemius, are visible near the limb in this view of the southern portions of Tethys' trailing hemisphere.

The far rim of Phemius disrupts the smooth profile of the icy moon's limb.

Features on Tethys are named for characters and places in "The Odyssey."

The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Nov. 24, 2008 at a distance of approximately 62,000 kilometers (38,000 miles) from Tethys and at a Sun-Tethys-spacecraft, or phase, angle of 94 degrees. Image scale is 366 meters (1,200 feet) per pixel.

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. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.