Mare Undarum
Mare Undarum is an uneven lunar mare located just north of Mare Spumans on the lunar near side, between the crater Firmicus and the eastern limb. It is one of the many elevated lakes contained in the Crisium basin, surrounding Mare Crisium. The selenographic coordinates of this mare are 6.8° N, 68.4° E. It has a maximum diameter of 243 km.
The surrounding basin material is of the Nectarian epoch, with the mare basalt being of the Upper Imbrian epoch. The crater Dubyago can be seen on the southern edge of the mare. On the northeastern edge of the mare is the crater Condorcet P.
When Mädler observed this area in the 1830s, he noted variations in the curved dark streaks that form this mare, leading him to speculate that the changes were caused by vegetation.
