Physical Effects of the Lipetsk Meteoroid: 2

Аннотация

Abstract—Comprehensive modeling studies of the processes induced in all geospheres by the passage and explosion of the meteoroid near the city of Lipetsk (Russia) on June 21, 2018, have been performed. Thermodynamic and plasma effects and the effects of the plume and turbulence accompanying the passage of the Lipetsk meteoroid have been estimated. It has been shown that the passage of the celestial body led to the formation of a gas–dust plume. The heated trail of the meteoroid cooled for several hours. Four stages of meteoroid-trail cooling are considered in detail. The first of these persisted for approximately 0.01 s, and the temperature of the trail decreased by a factor of two due to emissions. During the second stage (~1 s), the trail cooled due to emissions and expansion, and its temperature decreased by 15%. In the course of the third stage, which took approximately 3 s, the products of the explosion and the heated gas (thermal) with an acceleration of 100–200 m/s², attained an ascent rate of 200 m/s, and the temperature decreased by 10%. The fourth stage persisted for 100 s, during which the thermal absorbed the cool air at an intensive rate, gradually cooled off, and decelerated. The maximum altitude of rise of the thermal reached 15–20 km. The products of the explosion (dust particles and aerosols) contained in the thermal further participated in the following three processes: a slow precipitation to the surface of the Earth, turbulent mixing with the ambient air, and transport by the predominant winds around the globe. The effect of turbulence in the trail has been shown to be well pronounced, while the effect of magnetic turbulence has been weakly displayed. The following basic parameters of the plasma in the trail have been estimated: the altitude dependences of the electron densities per unit length and per unit volume, their relaxation times, the particle collision frequencies, the plasma conductivities, and the electron temperature relaxation time. At the initial time point, the linear and volume electron densities in the trail have been shown to be equal to approximately (2–40) × 10²³ m^–1 and (1–4) × 10²¹ m^–3, respectively, and the plasma conductivity to be equal to ~10³ Ohm^–1 m^–1. The role of the dusty plasma component is discussed.