On the roof at 5am this morning with chair and binoculars. Perfect third quarter moon in the southeast, with Jupiter in the east. Very clear, light wind. Here’s what I saw through the binoculars:
Alright, that crater wasn’t quite so prominent, but the two mountain ranges seemed about as defined as the drawing, which is by Galileo Galilei published in Sidereus Nuncius, 1610. As Galileo describes it, “brighter ridges of mountains rise loftily out of the darkness.”
The lower range is the Appenine Mountains, and the upper range the Alps. The best guess for Galileo’s crater is Albategnius, from Ewen A. Whitaker in “Galileo’s Lunar Observations and the Dating of the Composition of ‘Sidereus Nuncius,’ ” Journal for the History of Astronomy 9 (1978): 155-69.