Ariadaeus (Moon)

Named after Philip III of Macedonia Ariadaeus - chronologer (c. 358-317 B.C.).

Ariadaeus is a small, bowl-shaped lunar impact crater on the western shores of Mare Tranquillitatis. It lies to the north of the crater Dionysius, and to the west-southwest of Arago. The crater is joined along the northeast rim by the slightly smaller Ariadaeus A, and the two form a double-crater. (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.