Geological Chronicle
Mendeleev is an expansive walled plain on the lunar far side, spanning 325.13 kilometers in diameter with a southern rim that just crosses the lunar equator. Classified as a peak-ring basin lacking a central peak, the structure formed during the Nectarian period. Deposits of the Cayley Formation of Imbrian age cover its interior floor, while neighboring impacts intrude into its margins, including Schuster along the eastern rim and Hartmann on the west-southwestern rim.
A collection of named interior craters outlines a rough pentagon formation across the basin floor. Along the western inner wall lie Bergman to the west-northwest and Moissan to the west. Fischer and Richards form the northern side of the pentagon, while Harden sits near Schuster and Benedict lies southeast of the basin midpoint. Mendeleev P, located to the south-southwest, is the largest crater within the basin and its only designated satellite crater.
Across the western half of the floor extends Catena Mendeleev, a chain of tiny craters trending from the southwest to tangentially graze the western rim of Richards. The line points directly toward Tsiolkovskiy crater to the southwest and is thought to consist of secondaries from that impact. Formally named in 1961 by the International Astronomical Union in honor of Russian chemist Dmitri Mendeleev, the basin was also known as Basin IX until the early 1970s.