On the problem of the Tunguska meteorite material

The approximate composition of the Tunguska meteorite remnants obtained by averaging the results of several measurements is presented. It is pointed out that the matter of the cosmic-body remnants was enriched with alkaline and alkaline-earth elements. The composition of the meteorite matter was extremely heterogeneous. The upper limit of the density of the Tunguska cosmic body has been estimated at 2.8 g/cm³. It is suggested that, due to interaction with the Earth’s atmosphere, the cosmic body disintegrated into fragments from 10^?7 to 10^?3 m in size, with the majority of the matter being ejected to the upper atmospheric layers. Calculations of the rate and the time of the sedimentation of particles in the atmosphere have shown that the change in atmosphere transparency is controlled by particles larger than 10^?5 m in radius.