Rupes /ˈruːpɪs/ (plural /ˈruːpiːz/)[1] is the Latin word for 'cliff'. It is used in planetary geology to refer to escarpments on other worlds. As of January 2013[update], the IAU has named 62 such features in the Solar System, on Mercury (17), Venus (7), the Moon (8), Mars (23), the asteroids Vesta (2) and Lutetia (2), and Uranus's satellites Miranda (2) and Titania (1).[2][failed verification]
How rupes formed is, as of 2008[update], a matter of speculation. Compressional strain from the cooling of the crust of terrestrial planets and large-scale displacement due to impacts are the two dominant theories.[3]