Depth/diameter relations of fresh lunar craters: Revision from spacecraft data

The first systematic data from Apollo photogrammetry provide a high standard of accuracy for the depth/diameter (R i /D r ) relation of fresh lunar craters. Apollo R i /D r results resemble results obtained by measuring shadows on Lunar Orbiter imagery. The R i /D r distribution inflects at a crater diameter of 10 km ‐ 15 km. Lunar craters less than 15 km across are at least 50% deeper than older, telescopic data indicated (now, R i is ∼0.2 D r ), but larger craters are not much deeper. There is no marked R i /D r difference between fresh upland and postmare craters. The new R i /D r relation for small lunar craters resembles those of experimental and impact craters on Earth.