MacMillan is a bowl-shaped lunar

impact crater An impact crater is a circular depression in the surface of a solid astronomical object formed by the hypervelocity impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact crater ...

on the eastern fringes of the

Mare Imbrium Mare Imbrium (Latin ''imbrium'', the "Sea of Showers" or "Sea of Rains", "Sea of Tears") is a vast lunar mare, lava plain within the Imbrium Basin on the Moon and is one of the larger craters in the Solar System. The Imbrium Basin formed fro ...

. It was named after American mathematician and astronomer

William Duncan MacMillan William Duncan MacMillan (July 24, 1871 – November 14, 1948) was an American mathematician and astronomer on the faculty of the University of Chicago. He published research on the applications of classical mechanics to astronomy, and is noted fo ...

. It is located just to the southwest of a lone rise, near the southwestern edge of the Montes Archimedes. This is a cup-shaped depression in the surface with an interior

albedo Albedo (; ) is the measure of the diffuse reflection of solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body that refl ...

that matches the nearby

lunar mare The lunar maria (; singular: mare ) are large, dark, basaltic plains on Earth's Moon, formed by ancient asteroid impacts on the far side on the Moon that triggered volcanic activity on the opposite (near) side. They were dubbed , Latin for 'seas' ...

. The edges of the rim have a somewhat higher albedo. It shows some indications of a concentric crater. This crater was previously identified as Archimedes F.

References

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External links

Beer Lunar Topographic Orthophotomap
LTO41A4, May 1974 {{Commonscat Impact craters on the Moon Mare Imbrium