Stadius (Moon)

Named after Stade, Jan Stadius - Belgian astronomer, mathematician (1527-1579).

Stadius is a ghostly remnant of an ancient lunar crater that has been nearly obliterated by basaltic lava flows. It lies to the southwest of the much younger crater Eratosthenes, at the north edge of Mare Insularum where the mare joins Sinus Aestuum. To the west is the prominent ray crater Copernicus, and multiple secondary craters from the Copernican ejecta cover this area. To the northwest is a chain of craters that continue in a roughly linear formation until reaching Mare Imbrium. (wikipedia entry)

A crater is a circular depression likely created by an impact event. On the Moon they are named after deceased scientists, polar explorers, astronauts or cosmonauts.