Alexander is a lunar

impact crater An impact crater is a depression (geology), depression in the surface of a solid astronomical body formed by the hypervelocity impact event, impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal c ...

-like feature in the rugged surface to the north of Mare Serenitatis. It lies to the south-southwest of the prominent crater Eudoxus, and to the east-northeast of Calippus. It was named after

Alexander the Great Alexander III of Macedon (; 20/21 July 356 BC – 10/11 June 323 BC), most commonly known as Alexander the Great, was a king of the Ancient Greece, ancient Greek kingdom of Macedonia (ancient kingdom), Macedon. He succeeded his father Philip ...

The Alexander formation has been so heavily worn and distorted with the passage of time that it now resembles little more than a lowland region enclosed by rugged ranges. The rim segments lie along the northwest, west, and south sections of the crater, while the eastern side stands open to the surrounding surface. The surviving walls are nearly rectangular in form, with the most prominent mounts in the northwest. The crater floor is more smooth and has a darker

albedo Albedo ( ; ) is the fraction of sunlight that is Diffuse reflection, diffusely reflected by a body. It is measured on a scale from 0 (corresponding to a black body that absorbs all incident radiation) to 1 (corresponding to a body that reflects ...

in the western half, and gradually grows lighter and more impacted toward the east. There are no craters of significance within the perimeter of this formation, although there are tiny craterlets aplenty in the rougher eastern section.

Satellite craters

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Alexander.

References

* * * * * * * * * * * {{Craters on the Moon: A–B Impact craters on the Moon