Nicolai (Moon)

Named after Friedrich Bernhard Gottfried Nicolai - German astronomer (1793-1846).

Nicolai is a lunar crater that is located in the southern hemisphere , in a region that is less disturbed by significant impacts than most of the highlands. It is 42 kilometers in diameter and reaches a depth of 1.8 kilometers. The outer wall of this crater is worn, with a number of tiny craterlets lying along the rim. (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.