July 22, 2013
25" of Albategnius
image by Sergio Alonso (Zerjillo) and Antonio Román, Chirivel, Spain
LPOD has told the story of this crater a few times. Like nearby Ptolemaeus Albategnius has a flat, featureless floor, until low illumination reveals a series of shallow saucers. Unlike Ptolemy where most of the saucers are circular depressions, here there are also three or four elongated saucher-troughs that appear to be composed of multiple touching pits. These look like buried secondary crater chains, an interpretation strengthened by their general radial alignment with the Imbrium Basin. Presumably the smooth material filling both Albat and Ptolemy is ejecta from the formation of the Imbrium Basin that arrived in enough of a fluidized (or powdered?) state that it could collect in crater floors. Ptolemy is only 2.4 km deep, whereas Albat is 3.2 km, so its fill is not so deep; which we already knew because its central peak is well exposed.
30/06/2013. Obsession 25" reflector + QHY-5 camera; ~1000 frames captured and later processed with AVIStack, Regisax, ImagesPlus and GIMP.
21st Century Atlas charts 12 & 13.
An earlier 10" view
Yesterday's LPOD: Not My Favorite Names
Tomorrow's LPOD: The Far Wall