Definitions for "Riemann"
Keywords:  vestine, mahn, libration, gauss, ree
Riemann (pronounced REE mahn) is a lunar crater that is located near the northeastern limb of the Moon, and can just be observed from the side when libration effects bring it into sight. It lies to the east-northeast of the large Gauss walled plain. To the southeast, beyond sight on the far side, is the Vestine crater.
Keywords:  euclidean, geometry, pioneer, non
pioneer of non-Euclidean geometry (1826-1866)