Tags: Crater.
Thiessen is a lunar impact crater that lies in the far northern latitudes on the far side of the Moon. To the west of Thiessen is the younger crater Ricco and to the south-southwest is Roberts. Farther to the east lies Heymans.This is a heavily worn crater with overlapping impacts along the rim to the northeast northwest and west. A small crater occupies the northwestern interior floor. The remaining rim is worn and rounded and the crater is now essentially a depression in the surface.