The radial structure of this magnificent crater is reminiscent of Copernicus. Although its albedo is exacly equal to the avearage for the lunar surface - 0.12 - it is still very prominent against the smooth dark Mare Nubium (albedo 0.04).

Photo: António Cidadão. His Home Page of Astrophotography includes stereograms, animations, and "Seven Craters a Week" from his forthcoming photographic lunar atlas.

Inconstant Moon