On Models of Meteoroids Fragmentation in the Atmosphere

Abstract

Different approaches are developed to modelling the destruction of cosmic bodies in the atmosphere into a large number of fragments. It is assumed that they first move with a common shock wave as a single body deformed by pressure forces. Four models of meteoroid disruption into a cloud of fragments are considered: two developed by the authors, and two generally accepted. The main differences between the models are showed. Using these models, numerical solutions of the meteor physics equations taking into account ablation are obtained to simulate the interaction of the Chelyabinsk meteoroid with the atmosphere. Solutions for different models are compared with each other and with observational data. After meteoroid’s fragments diverge over a long distance, their independent movement is considered. Formulas for the probability and cumulative distribution of fragments by mass are obtained using the results of experiments on the destruction of bodies under high-speed impact. The cumulative distribution is compared with the experimental data and also with the mass distributions of the recovered meteorites in the cases of a significant number of fragments found. The mass and luminosity of the disrupted meteoroid are determined by integration over all fragments using the probabilistic mass distribution as the initial one. The mass and velocity of each fragment are determined from the meteor physics equations.