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Lunar #75: Ptolemaeus B

Ptolemaeus is a large crater of 154 km diameter with a flat, lava-flooded floor. Just north (up and left) is Herschel with 42 km diameter. A number of small craters lie within Ptolemaeus, among these the prominent Ammonius with 8 or 9 km diameter. Just above this lies a very difficult to detect ghost crater Ptolemaeus B, which at 19 km diameter is the object in question here.

Image:

1. The area in two images taken on 2022-12-15 and 2023-05-27, resp., stacked from 700 video frames each, taken with a Schmidt-Cassegrain reflector of D = 200 mm and f = 3500 mm and Canon EOS 600Dα camera. Wavelet sharpening. The phase was −62% and +52%, resp.
2. Dto., annotated.