Mare Cognitum (Latin for "known sea") is a small lunar sea that forms the southeast of the Oceanus Procellarum basin and is located a little west of the visible center of the moon.
It has an average diameter of 350 km and borders the Montes Riphaeus mountains in the northwest and the Mare Nubium in the southeast . Its center point has the selenographic coordinates 11 ° south and 22 ° west.
Apollo 14 landed at Fra Mauro crater near Mare Cognitum. This was examined more closely for the first time in 1964 with the photo series of the Ranger 7 impact probe .