Mare Insularum is located in the Insularum basin, just
south of Mare Imbrium. The basin material is of the
Lower Imbrian epoch, with the mare material of the
Upper Imbrian epoch. The mare is bordered by the
craters Copernicus on the East, and Kelper on the west.
Oceanus Procellarum joins the mare to the southwest.
Copernicus is one of the most noticeable craters on
the moon, seen as the white region on the photo. The
rays from both Kepler and Copernicus protrude into the
mare.The northern edge of Mare Cognitum is visible
at the bottom of the photo, and Fra Mauro is the grey
patch in the lower right.