Van de Graaff (Moon)

Named after Robert Jemison Graaff - American physicist (1901-1967).

Van de Graaff is an unusual lunar formation that has the appearance of two merged craters, approximately in a figure-8 shape with no intervening rim separating the two halves. The crater is located on the far side , on the northeast edge of Mare Ingenii. The crater Birkeland is attached to the southeast rim, nestling against the slightly narrower "waist" of the formation. To the north is Aitken, and Nassau lies to the east. (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.