Philolaus is a lunarimpact crater that is located in the northern part of the Moon's near side. It lies within one crater diameter to the east-southeast of the flooded crater Anaximenes, and to the west of the smaller Anaxagoras. It overlies the older and heavily worn Philolaus C to the south.
This crater retains a well-defined form that has not changed significantly since it was originally created. The outer rim edge is roughly circular, but with a somewhat irregular edge that displays signs of slumping. The most notable slump is a triangular area along the eastern rim. The inner wall of the crater has a complex system of terraces with a sharp-edged rim in locations where slumping has occurred. On the exterior of the rim is an outer rampart that extends outwards for nearly half a crater diameter in all directions. The crater has a ray system, and is consequently mapped as part of the Copernican System.[1]
The interior floor is irregular with rough areas about the center and to the northeast. There is no single central peak, but rather a pair of peaks offset to the south and the east of the middle. There is also a smaller ridge pair offset to the northwest. The flattest part of the interior floor is in the northeast of the crater interior. The floor is not significantly marked by impacts.
^The geologic history of the Moon, 1987, Wilhelms, Don E.; with sections by McCauley, John F.; Trask, Newell J. USGS Professional Paper: 1348. Plate 11: Copernican System (online)
Andersson, L. E.; Whitaker, E. A. (1982). NASA Catalogue of Lunar Nomenclature. NASA RP-1097.
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.