On Models of Meteoroid Fragmentation in the Atmosphere

Various approaches are developed for modeling the destruction of cosmic bodies in the atmosphere into a large number of fragments. It is assumed that, at first, they move with a common shock wave as a single body deformed under the action of pressure forces. Four models of meteoroid fragmentation into a cloud of fragments are considered: two developed by us and two that are generally accepted. The main distinctions between the models are revealed. These models are used to obtain numerical solutions of the equations of meteor physics taking into account ablation to calculate the interaction of the Chelyabinsk meteoroid with the atmosphere. Solutions for different models are compared with each other and with observational data. After the fragments diverge over a large distance, their independent motion is considered. For the probabilistic and cumulative mass distribution of fragments, formulas 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 with the mass distributions of recovered meteorites in the cases of a significant number of found fragments. The mass of the fragmented meteoroid and the luminosity are found by integrating over all fragments using their probabilistic mass distribution as the initial one. The mass and velocity of each fragment are determined from the equations of meteor physics.