Saturn's moon Iapetus, showing the curious 20 km-wide topographic ridge that coincides almost exactly with the geographic equator.
Four images create this view, taken by Cassini on 31 December 2004 from a distance of about 172 400 km. The image scale is 1 km/pixel. More information.
The Cassini-Huygens mission is a cooperative project of NASA, ESA and the Italian Space Agency.