Cratering Experiments into Curved Surfaces and Their Implication for Craters on Small Satellites

Abstract

Impact craters were produced on mortar targets of cylindrical, spherical, and plane surfaces in order to evaluate the effect of curvature on the shape of large craters on nonplanar surfaces of smaller bodies. As the curvature of the target surface increases, the cross-sectional shape of the crater becomes flatter, and the crater diameter and ejecta mass increase. Diameter and ejecta mass of craters on a convex spherical surface are larger than those on cylindrical surfaces of the same curvature. The crater on the concave spherical surface has a smaller diameter, less ejecta mass, and a deeper bottom. Crater shape rapidly changes as the crater radius grows comparable to the curvature radius of the target surface. Some of these results agree on a cross-sectional shape of a large crater on Phobos. The cross-sectional shape of a large crater observed on Hyperion is also compared to the experiments.