The Moon's Apennine mountains

The Moon

. The radial structure and steep inner slopes of these mountains (lower right) mark a section of the outer rim of the Imbrium Basin. The huge excavation was subsequently filled with lava to form the smooth Mare Imbrium and partially submerge the inner ring of mountains (upper left). The smaller circular craters include Timocharis (Fig. 2.16), about 34 thousand meters in diameter (center left) and the largest round structure Archimedes (upper center) with a diameter of 83 thousand meters. (Courtesy of the Lick Observatory.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University