... Ancient Craters of Southern Rhea . ... Credit: Cassini Imaging Team , SSI , JPL , ESA , NASA Explanation: Saturn's ragged moon Rhea has one of the oldest surfaces known. ... Like Earth's Moon , Rhea's rotation is locked on Saturn, and the above image shows part of Rhea's surface that always faces Saturn. ... The above image was taken by the robot Cassini spacecraft now orbiting Saturn. ... Publications with keywords: Rhea - cassini spacecraft . ... Saturns Moon Epimetheus from the Cassini Spacecraft...