Alfraganus (crater)
Crater on the Moon
From Wikipedia, the free encyclopedia
Alfraganus is a small, deep lunar impact crater that lies in the rugged highland region to the southwest of the Mare Tranquillitatis.[3] Northwest of Alfraganus is the crater Delambre, and to the south is the irregular Zöllner.
Lunar Orbiter 4 image | |
| Coordinates | 5.4°S 19.0°E |
|---|---|
| Diameter | 20.52[1] km |
| Depth | 3.8[2] km |
| Colongitude | 343° at sunrise |
| Eponym | Alfraganus |
This impact is dated to the Copernican period, so it is relatively young.[4] The rim of Alfraganus is circular and retains a sharp edge that has not received a significant amount of wear due to subsequent impacts. The interior floor is roughly half the diameter of the crater rim,[5]: 78 with two ridges aligned at right angles to each other. The crater lies at the center of a minor ray system.[6]
This crater is named after the Muslim astronomer Alfraganus (unknown – c. 840). Its designation was formally adopted by the International Astronomical Union in 1935.[1] The name was introduced into lunar nomenclature by Italian astronomer G. B. Ricciolli in 1651.[7]
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 Alfraganus.
| Alfraganus[5]: 291 | Latitude | Longitude | Diameter |
|---|---|---|---|
| A | 3.0° S | 20.3° E | 13 km |
| C | 6.1° S | 18.1° E | 11 km |
| D | 4.0° S | 20.1° E | 8 km |
| E | 4.6° S | 19.0° E | 4 km |
| F | 3.5° S | 20.8° E | 9 km |
| G | 2.6° S | 21.2° E | 6 km |
| H | 4.4° S | 19.1° E | 13 km |
| K | 5.3° S | 19.5° E | 4 km |
| M | 5.6° S | 19.6° E | 3 km |
