This deep crater (bottom left) is very close to the limb. With favourable libration its multiple central peaks are visible, but at other times it might not be visible at all. Between Zucchius and the elongated Schiller (top) lies an unnamed basin 350km across.

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