Named after Jemma, Reinier Gemma Frisius - Dutch doctor (1508-1555).
Gemma Frisius is a lunar crater that is located in the rugged southern highlands. It lies to the north of the walled plain Maurolycus, and southeast of the smaller crater Poisson. The crater Goodacre is attached to the northeast rim. The outer wall of this crater has been heavily damaged by impacts, particularly along the north and west sides. (wikipedia entry)
