It lies in the southwest sector of the Moon, near the lunar limb.
Farther to the southwest is Balboa, near the lunar limb.
It lies along the southern lunar limb, and so is viewed from the side by an observer on the Earth.
Langrenus is a prominent impact crater located near the eastern lunar limb.
It lies beyond the eastern lunar limb in an area that is only visible during favorable librations.
From the Earth the crater appears on the northern lunar limb, and is seen from the side.
It lies just behind the southern lunar limb, in a region that is sometimes brought into view of the Earth due to libration.
This study was based upon roughly 700 photographs of the lunar limb taken between 1927 up until 1956.
Pythagoras is a prominent impact crater located near the northwestern lunar limb.
He is most noted for his measurements of features near the lunar limbs.
