mountains, lunarRaised regions on the Moon, most of which consist of crustal blocks uplifted to define the multiple ring structures of impact basins; these survive either as ring mountains, such as the Apennines, or as isolated peaks, such as La Hire (see table). In comparison the lunar highlands are topographically higher than the maria but are characterized more by the elevated rims of craters and the rolling hills of basin ejecta blankets. Discrete mountains not associated with impact basins include the central peaks of craters, such as Tsiolkovsky, and volcanic domes and plateaus. Despite their jagged appearance, few mountains have slopes that exceed 12°.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006