Van't Hoff is a lunar crater that is located to the northeast of the walled plain Birkhoff, on the far side. To the northwest is the crater Stebbins, and to the east lies the smaller Dyson. This crater lies at high northern latitudes of the lunar surface, almost two-thirds the way from the equator to the pole. The outer rim is heavily eroded and the crater has become distorted in shape by subsequent impacts. (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.