What is "maclear"

Maclear is a lava-flooded crater on the northwest part of the Mare Tranquillitatis, a lunar mare in the eastern half of the Moon. The crater is located to the southeast of the slightly larger Ross. To the southwest of Maclear 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. The rim is not quite circular, having a flat outward bulge along the western side. But the rim is relatively uniform in width and is not significantly eroded.

The crater rim lies at the southern terminus of a rille belonging to a system that runs along the western edges of Mare Tranquillitatis. The rille system to the north of the crater is designated Rimae Maclear, while the rilles to the south-southwest are named Rimae Sosigenes. The Rimae Maclear stretches for about 100 kilometers, reaching Al-Bakri to the north along the edge of the mare.

It is named after Sir Thomas Maclear, Her Majesty's astronomer at the Royal Observatory, Cape of Good Hope ( Cape Town, South Africa), from 1833 to 1870.

Maclear may refer to:

• Sir Thomas Maclear (1794 – 1879), Irish-born South African astronomer
• Michael Maclear (born 1929), Canadian journalist, documentary filmmaker, and former correspondent
• John Maclear (1838 - 1907), commander of the HMS Challenger from 1872 to 1876

• Maclear, Eastern Cape, a town in the Eastern Cape province, South Africa
• Maclear Island (Queensland), an island in the Great Barrier Reef Marine Park
• Maclear (crater), a lunar crater

• Maclear's Rat, an extinct species of rat formerly found on Christmas Island