Saturn’s moons Iapetus (left), Mimas, and Dione show fascinating histories. One hemisphere of Iapetus is almost pure white, while the other (peeking into view at left) is as dark as coal. It also features a huge impact crater. The impact that gouged the large crater on Mimas almost blasted the little moon to bits. And Dione shows giant cracks, which may have formed as the moon cooled and shrank. [NASA/JPL (3)]
Find out more in our radio program entitled Moon and Saturn.