Geological Chronicle
Located in the northern part of the Moon's near side, Philolaus measures 71.44 kilometers in diameter. It lies east-southeast of the flooded crater Anaximenes, west of the smaller Anaxagoras, and directly overlies the older, heavily worn crater Philolaus C to the south. The feature honors Philolaus of Croton, a Greek mathematician, astronomer, and philosopher.
The crater retains a well-defined form that has not changed significantly since its formation. A complex system of terraces lines the inner wall, while an irregular outer rim exhibits signs of slumping, notably along a triangular section on the eastern edge. Outside the rim, an outer rampart extends outward for nearly half a crater diameter in all directions, and an associated ray system places the structure within the Copernican System.
Across the interior floor, rough ground surrounds the center and northeast rather than a single central mountain. Instead, a pair of peaks rises offset to the south and east of the middle, accompanied by a smaller ridge pair to the northwest. The flattest terrain lies in the northeast, and the floor remains largely free of subsequent impact scars.