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Lunar #94: Drygalski

The crater Drygalski is 164 km in diameter on the southern limb at longitude and latitude −87.2°, −79.6°. The best phase is a about a day before Full Moon, but the libration has to be right, such that the South Pole is tilted towards Earth. Find your way from Blancanus via Klaproth and Casatus. Then look for the small, but prominent le Gentil A. Compare your observation with the Atlas virtuel de la Lune, in particular using its global face-on view to remove the perspective foreshortening (Chevalley and Legrand 2012a). This appears as a large crater with flat floor to the right of the central mountain and a hilly area to its left.

Refer to Wood's list (2004a and 2012a) and to his notes (cf. Hardwick 2013a). Compare your observation with the Atlas virtuel de la Lune (Chevalley and Legrand 2012a). In this atlas, at high resolution, in general, consider a photographic texture like the LRO WAC mosaic as well as the synthesised topography of the LOLA Kaguya Shade texture. For regions near the lunar limb, changing from the foreshortened Earthlings' perspective to the vertical view down on the Moon can be instructive.

Images:

1. The area on 2022-12-15, stacked from 700 video frames 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%, libration was −4.8° in longitude and −5.4° in latitude.
2. Dto. with annotation and scale.
3. Annotated screenshot from Atlas virtuel de la Lune using the shaded relief texture.