Radiation phenomenon for large meteoroids

Abstract

Aims. The relationship between the intrinsic properties of a large meteoroid, that is, mass, density, chemical composition, and flight velocity, and its spectrum are identified. Methods. Assuming thermochemical equilibrium and inviscid flow and using a quasi-one-dimensional approach, the flow-field and radiative transfer problems are solved from the ablating wall of a meteoroid to the observer on the ground. Results. The study discovers that the precursor region immediately ahead of the shock layer absorbs nitrogen and oxygen lines, and thereby modifies the spectrum received by the ground observer. The study leads to a computer code with which the observed spectra and light-curves for Benesov and Sumava meteoroids are numerically and approximately reproduced with the help of a meteoroid fragmentation theory. Luminous efficiency value is obtained as a byproduct.