AN ANALYTICAL MODEL OF THE MOTION OF LARGE METEORS IN THE ATMOSPHERE AND ITS APPLICATION TO THE REAL EVENTS

摘要

In the processing the observed meteors and fireballs data, we widely exploit the conception of the photometric mass, which is based on theory of radiation of a meteor body. This theory used by many authors almost for all meteor events was developed by OEpik (1933, 1955) only for relatively small meteors, not more than a few cm in diameter. Here we consider an alternative method for estimating parameters of large meteors which is based on the analysis of observed deceleration. On the basis of existing analytical model (Gritsevich, 2008a) Canadian and US meteors with large dynamic mass are presented. The detail calculations clearly show that the major part of the luminous segment of the trajectories of large meteors corresponds to continuous medium flow, while the condition of a free molecular flow holds outside this segment. The maximum brightness altitude is smaller than that at which a strong bow shock is formed. Therefore, we can assume that the meteor brightness under these conditions is mainly due to the emission from air in the compressed shock layer rather than due to the emission from evaporated meteor matter which is necessary for the validity of the famous photometric formula.