Mare Nubium ("sea of clouds") is a
lunar mare in the Nubium basin on the Moon's near side. The mare is located just to the southeast of
Oceanus Procellarum. The actual basin is believed to be of
Pre-Nectarian[?] system, with the surrounding basin material being of the
Lower Imbrian[?] epoch. The mare material is of the
Upper Imbrian[?] epoch. The crater to the east of the mare is
Bullialdus[?], which is of the
Eratosthenian[?] Epoch. This means the crater is younger than the mare it sits in. The crater that sits on the southern rim of the mare is
Pitatus[?].