Shown here is the trailing hemisphere of Iapetus, one of Saturn's most unusual moons, where some regions are as dark as coal and others as bright as snow, captured from roughly 75,000 kilometers away. A large impact crater spanning 500 kilometers is visible in the south, superimposed on an older structure of similar size. The dark material, likely carbon-rich residue from sublimated dirty ice, increasingly coats the eastern portion of the moon, covering craters and highlands alike.