Ammonius (Moon)

Named after Ammonius - Greek philosopher (unkn.-c. A.D. 517-526).

Ammonius is a bowl-shaped lunar impact crater with a slightly raised rim. It is located on the floor of the walled plain Ptolemaeus, about 30 kilometers northeast of the crater midpoint. (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.