Ammonius (crater)
Crater on the Moon
From Wikipedia, the free encyclopedia
Ammonius is a bowl-shaped lunar impact crater with a slightly raised rim. It is located on the floor of the walled plain named Ptolemaeus,[3] about 30 kilometers northeast of the crater midpoint.[4]
Slightly oblique view from Apollo 16, facing east | |
| Coordinates | 8.5°S 0.8°W |
|---|---|
| Diameter | 8.55 km (5.31 mi)[1] |
| Depth | 1.54 km (0.96 mi)[2] |
| Colongitude | 1° at sunrise |
| Eponym | Ammonius Hermiae |
Just to the north on the lava-flooded floor of Ptolemaeus is a relatively prominent "ghost" crater: the discernible buried rim of a pre-existing crater.[3] The diameter of this ghost crater is nearly double that of Ammonius, and is currently identified as Ptolemaeus B.[5]
The crater is named after Greek philosopher Ammonius Hermiae (c. A.D. 517–526). In the past this crater was identified as Ptolemaeus A,[6] before being named by the IAU in 1976.[1][5]
