Cosmic Blasting Zone

Saturn's impact-pummeled Hyperion stares back at Cassini in this six-image mosaic taken during the spacecraft’s close approach on Sept. 26, 2005. This up-close view shows a low density body blasted by impacts over the eons. Scientists originally believed that the spongy appearance of Hyperion is caused by a phenomenon called thermal erosion, in which dark materials accumulating on crater floors are warmed by sunlight and melt deeper into the surface, allowing surrounding ice to vaporize away.