Regiomontanus (crater)

Regiomontanus is an ancient lunar impact crater located in the southern highlands region to the southeast of Mare Nubium.

The crater is heavily worn from impact erosion, and the rim is irregular, mountainous and distinctly oval in outline.

A prominent ridge lies off-center to the northwest, with the small crater Regiomontanus A at its summit.

[1] Like many of the craters on the Moon's near side, it was given its name by Giovanni Riccioli, whose 1651 nomenclature system has become standardized.

[4] By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Regiomontanus.

Regiomontanus as seen from Earth during the first quarter of the Moon
Regiomontanus crater and its satellite craters taken from Earth in 2012 at the University of Hertfordshire's Bayfordbury Observatory with the telescopes Meade LX200 14" and Lumenera Skynyx 2-1