Mare Cognitum (the "sea that has become known") is a
lunar mare located in a basin or large
crater which sits in the sencond ring of the
Procellarum basin. The basin material is of the
Lower Imbrian[?] epoch, while the
basaltic mare material is of the
Upper Imbrian[?] epoch. To the northwest of the mare is the
Montes Riphaeus mountain range, part of the rim of the buried crater or basin containing the mare.
Fra Mauro, the landing site of Apollo 14, is located near Mare Cognitum.