The crater Porter is located to the north-northeast of Rutherfurd, on the northeastern rim of Clavius.

Rutherfurd forms the larger member in an arcing chain of craters of decreasing size that curves across the floor of Clavius.

The ejecta pattern, oblong shape, and location of the central peak indicate the original impact may have been at a low angle from the southeast.

[1] The crater was named by and for astrophotographer Lewis Morris Rutherfurd who took the first telescopic photographs of the moon.

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