FRAGMENTATION MODEL FOR IMPACT CLUSTERS ON MARS

Abstract

In recent years, about 1200 of fresh meteoroid impact sites were discovered on Mars, they are single craters and crater fields. Due to the rarefied atmosphere of Mars (compared with Earth), the falling meteoroids are destroyed less, nevertheless, about half of them fragment in the Martian atmosphere and form crater fields of scattering (clusters). The study of crater clusters on Mars allows us to study the details of fragmentation, which cannot be detected on Earth. The initial results of numerical modeling of the interaction of a meteoroid with the atmospheres of Mars and Earth are considered. A comparison of fragmentation simulation results showed that the size of the scattering field on Earth is many times larger than on Mars. In the Earth›s atmosphere the fragments reach the surface without forming craters and there is atmospheric sorting of fragments. It is demonstrated that the final location of small meteorite fragments depends significantly on the chosen expression for the drag coefficient. Crater fields on Mars are largely determined by fragmentation and fragment dispersal, the effect of atmospheric sorting has little effect. The results obtained for the Martian atmosphere suggest that the serial implementation of the developed fragmentation model will allow to describe clusters and offer better methods for estimating the flight direction and properties of the impactor.