Nicolai is a lunar impact crater that is located in the southern hemisphere of the Moon, in a region that is less disturbed by significant impacts than most of the highlands. The nearest craters of note are Spallanzani to the south, and the much larger Maurolycus and Barocius to the east. The crater is named after the 19th-century German astronomer Friedrich Bernhard Gottfried Nicolai. It is 42 kilometers in diameter and reaches a depth of 1.8 kilometers.
Satellite craters
By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Nicolai.
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