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Focas is a small lunar impact crater that lies on the far side of the Moon, just past the southwestern limb. In this location the crater is occasionally brought into view due to libration, but not much detail can be seen because the crater is viewed from the side.

Focas crater WAC.jpg
LRO WAC image
Coordinates33°42′S 93°55′W / 33.7°S 93.91°W / -33.7; -93.91Coordinates: 33°42′S 93°55′W / 33.7°S 93.91°W / -33.7; -93.91
Diameter10 km
Colongitude94° at sunrise
EponymIonnas Focas

The crater is situated in the wide valley between the ring-shaped Montes Rook in the north and Montes Cordillera range in the south. These ranges form a double-ring around the Mare Orientale impact basin. The crater is located toward the southern end of this immense feature, just to the north of the Montes Cordillera range. Focas is a relatively isolated crater, with the nearest craters of note being the WrightShaler crater pair some distance to the east along the same interior edge of the Montes Cordillera.

This is a circular crater with an interior floor about half the total diameter. It is symmetrical in form, with only some slight appearance of wear along the rim. The interior floor contains no features or impacts of note.

Focas Crater is named after Jean-Henri Focas (1909-1969), a Greco-French astronomer.

Satellite cratersEdit

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

Focas Latitude Longitude Diameter
U 32.7° S 98.5° W 10 km


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