Alexander (crater)
Encyclopedia
Alexander is a lunar
crater
-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
.
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
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.
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
crater
Impact crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
-like feature in the rugged surface to the north of Mare Serenitatis
Mare Serenitatis
Mare Serenitatis is a lunar mare that sits just to the east of Mare Imbrium on the Moon.It is located within the Serenitatis basin, which is of the Nectarian epoch. The material surrounding the mare is of the Lower Imbrian epoch, while the mare material is of the Upper Imbrian epoch...
. It lies to the south-southwest of the prominent crater Eudoxus
Eudoxus (lunar crater)
Eudoxus is a prominent lunar impact crater that lies to the east of the northern tip of the Montes Caucasus range. It is located to the south of the prominent crater Aristoteles in the northern regions of the visible Moon...
, and to the east-northeast of Calippus
Calippus (crater)
Calippus is a small lunar crater that is located on the eastern edge of the rugged Montes Caucasus mountain range in the northern part of the Moon...
.
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
Albedo , or reflection coefficient, is the diffuse reflectivity or reflecting power of a surface. It is defined as the ratio of reflected radiation from the surface to incident radiation upon it...
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 mid-point that is closest to Alexander.| Alexander | Latitude | Longitude | Diameter |
|---|---|---|---|
| A | 40.7° N | 14.9° E | 4 km |
| B | 40.3° N | 15.2° E | 4 km |
| C | 38.5° N | 14.9° E | 5 km |
| K | 40.5° N | 19.3° E | 4 km |