Segner is a lunarimpact crater located near the southwestern limb of the Moon, to the northeast of the giant walled plain Bailly. The crater Zucchius is a few kilometers to the south-southwest of the rim, and to the north east lies the unusual formation Schiller. The smaller crater Weigel is located to the east.
Segner has a low, worn rim, and is generally much less prominent than the nearby Zucchius. The floor is distinguished only by a pair of small craterlets and a slightly undulating surface. There is no indication of a central peak. A low ridge runs to the north from the edge of the northern rim.
Menzel, D. H.; Minnaert, M.; Levin, B.; Dollfus, A.; Bell, B. (1971). "Report on Lunar Nomenclature by the Working Group of Commission 17 of the IAU". Space Science Reviews. 12 (2): 136–186. Bibcode:1971SSRv...12..136M. doi:10.1007/BF00171763. S2CID122125855.