Wrinkly Moon

A large impact crater dominates this bit of Tethys, one of the moons of Saturn, which was photographed by the Cassini spacecraft on April 14. A much larger crater, Odysseus, is seen as a bright depression at the far right edge. The moon's icy surface has been battered by countless impacts, leaving the entire surface scarred and wrinkled. The craters tell planetary scientists that Tethys is an inactive world, with no ongoing geological processes to erase the craters, many of which are ancient. The image was snapped from a distance of about 12,000 miles (19,300 km). [NASA/JPL/SSI]