Euler (Moon)

Named after Leonhard Euler - Swiss mathematician (1707-1783).

Euler is a lunar impact crater located in the southern half of the Mare Imbrium. The most notable nearby feature is Mons Vinogradov to the west-southwest. There is a cluster of low ridges to the southwest, and this formation includes the small crater Natasha and the tiny Jehan. About 200 kilometers to the east-northeast is the comparably sized crater Lambert. (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.