| Coordinates: | 46°N -108.3°W |
| Diameter: | 125 km |
| Depth: | Unknown |
| Colong: | 110 |
| Eponym: | Joseph Stefan |
Stefan is a lunar impact crater on the far side of the Moon, just beyond the northwestern limb. Attached to the western rim is the slightly smaller crater Wegener, and close to the eastern rim is Rynin.
As with many craters of this size on the Moon, the outer rim has been worn by impact erosion and the edge and inner wall are generally pitted with small craterlets. The southern edge of the rim in particular has been damaged by impacts, and is overlain by the satellite crater Stefan L. This bowl-shaped crater lies at the center of a small ray system, which is indicative of a relatively young impact.
The interior floor of Stefan is a generally level surface that is marked by several impacts. The most notable is a ring-shaped crater rim projecting up through the southern half of the floor. Near the midpoint is a low hill, possibly the buried remnant of a central peak.
Stefan lies at the approximate margin of the Coulomb-Sarton Basin, a 530 km wide impact crater of Pre-Nectarian age.
By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Stefan.
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. Thomas William Webb . 1962 . Celestial Objects for Common Telescopes . 6th revised . Dover . 978-0-486-20917-3 .
. Ewen Whitaker . 1999 . Mapping and Naming the Moon . Cambridge University Press . 978-0-521-62248-6 .