Maclear (Moon)

Named after Sir Thomas Maclear - Irish-born South African astronomer (1794-1879).

Maclear is a lava-flooded crater on the northwest part of the Mare Tranquillitatis, a lunar mare in the eastern half. The crater is located to the southeast of the slightly larger Ross. To the southwest is Sosigenes, while farther to the south-southeast is Arago. With most of its interior submerged in deposits of basaltic lava, all that remains of this crater is a narrow rim projecting above the surrounding 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.