Visibility III / V
The steep light of the sunrise brought out ghost craters from the flat bottom of the Ptolemaeus crater, buried beneath the later strata (perhaps the finer flies that flew in the formation of the Imbrium basin). Traces of the Imbrium collision are also visible in the area as valleys pointing to the Imbrium, which is the making of larger bodies flying from the collision. One of them bevels a ruined crater north of Ptolemaeus, named after the Finnish Hugo Gyldén.
Near the Réaumur crater, north of Gyldén, there are two slopes, the Rima Oppolzer and the Rima Réaumur. The latter runs from Réaumur to the large, old crater of Hipparchus to its east.
To the east of Ptolemaicus is the central-peak Albategnius crater, on the edge of which is Klein, younger than Albategnius and smaller in name.
To the south of Ptolemaeus, the central peak of the Alphonsus crater rises to sunlight.