Luther (Moon)

Named after Carl Theodor Robert Luther - German astronomer (1822-1900).

Luther is a small lunar impact crater on the northwest part of Mare Serenitatis, at the inlet to Lacus Somniorum. Luther has a circular rim and is cup-shaped, with no appreciable wear from impact erosion. It lies across a wrinkle ridge on the lunar mare. (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.