Probable Hydrodynamic Mechanisms of Complex Crater Formation

It is known that on the Moon surface, a distinct mound is observed at the bottom of flattened craters. We put forward an assumption of the crater shape dependence on that of the meteorite. The computational experiment on investigating the features of super-speed bodies collision with the target revealed many types of craters depending on the shape of the impactor–meteorite, its velocity, gasodynamic characteristics and physical properties of the target. Among others, the following effects were discovered: the split-off emerging as a backward cumulative jet for impactors with the density lower than that of the target; existence of flattened craters with mounds inside; hollows inside the target mounds affected by impact, and cylindrical craters-wells formation in the process of impact.