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Lunar #47: Alphonsus dark spots

L47 main image L47 annotated

Alphonsus is a large crater (118 km diameter), the centre one of the prominent triplet with Ptolemaeus to the North and Arzachel to the South. Nominally, the object here are three or four dark spots of lava deposits inside the crater walls in the West, Southeast and Northeast. The central peak is quite high and illuminated at sunrise long before any light hits the crater floor. There are also the Rimae Alphonsus, running some distance inside the wall from the Southeast to the North.

Image:

  1. The area on 2023-02-28, 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 +64%.
  2. Dto., annotated and with scale.