Interaction of large Taurid meteoroids with the Earth's atmosphere

Abstract

Results of the detailed analysis of the luminosity and ablation of bright Taurid, that break up into individual pieces in the Earth's atmosphere due to the aerodynamic pressure are presented. The aim of this analysis is to determine the composition and strength of Taurids on the basis of both photographic observations with small-meteor cameras and cameras with long focal length using the method of instantaneous exposure (τexp = 5.6 × 10-4 s). The study was carried out by constructing the theoretical meteor light curve while taking into account its fragmentation into two or more pieces and analyzing the aerodynamic pressure on the meteoroid at the point of splitting. The bulk densities of Taurids were obtained from an analysis of the observed light curves and compared with the strength categories obtained on the basis the data of the aerodynamic pressure at the point of meteoroid splitting. Comparing the resulting values with the known strength properties of various materials lets us conclude that Taurids could be considered structurally fragile bodies that fall into the a-strength category, have a density of 2.3 to 2.8 g/cm3, and can be characterized as carbonaceous chondrites. We discovered a connection between observed low-frequency pulsations of brightness of the splitting Taurids and the flares of individual pieces. We suggested that the observed lateral displacement velocity of the pieces could be caused by the explosive nature of the process of Taurid meteoroid fragmentation.