Iapetus, ice moon of beautiful Saturn, the two-faced moon. It is gleaming white, bumpy and tradionally cratered in some places, ridged across most of the equator with a Death Star like giant circle on one side, and bruised black and blue, literally misshapen, across an entire hemisphere from what was no doubt an ancient wound of titanic proportions. Iapetus may also have the weirdest avalanches or debris slides, or whatever the term is, in the solar system:
BBC— The icy satellite has more giant landslides than any Solar System body other than Mars. The reason, says Prof William McKinnon, also from Washington University, is Iapetus’ spectacular topography.
“Not only is the moon out-of-round, but the giant impact basins are very deep, and there’s this great mountain ridge that’s 20km (12 miles) high, far higher than Mount Everest,” he explained. “So there’s a lot of topography and it’s just sitting around, and then, from time to time, it gives way.”