"We see landslides everywhere in the solar system," says Kelsi Singer, graduate student in earth and planetary sciences in Arts & Sciences at Washington University in St. Louis, "but Saturn's icy moon Iapetus has more giant landslides than any body other than Mars."
The reason, says William McKinnon, PhD, professor of earth and planetary sciences, 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 20 kilometers (12 miles) high, far higher than Mount Everest.