Measuring the Terminal Heights of Bolides to Under

Authors: Manuel MorenoIbáñez Maria Gritsevich Josep M TrigoRodríguez

Publish Date: 2017

Volume: , Issue: , Pages: 129-151

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Abstract

The extent of penetration into the Earth’s atmosphere of a meteoroid is defined by the point where its kinetic energy is no longer sufficient to produce luminosity For most of the cases this is the point where the meteoroid disintegrates in the atmosphere due to ablation process and dynamic pressure during flight However some of these bodies have particular physical properties bigger size higher bulk strength etc or favorable flight conditions lower entry velocity or/and a convenient trajectory slope etc that allow them to become a meteoritedropper and reach the ground In both cases we define the end of the luminous path of the trajectory as the terminal height or end height Thus the end point shows the amount of deceleration till the final braking We thus assume that the ability of a fireball to produce meteorites is directly related to its terminal height Previous studies have discussed the likely relationship between fireball atmospheric flight properties and the terminal height Most of these studies require the knowledge of a set of properties and physical variables which cannot be determined with sufficient accuracy from groundbased observations The recently validated dimensionless methodology offers a new approach to this problem All the unknowns can be reduced to only two parameters which are easily derived from observations Despite the calculation of the analytic solution of the equations of motion is not trivial some simplifications are admitted Here we describe the best performance range and the errors associated with these simplifications We discuss how terminal heights depend on two or three variables that are easily retrieved from the recordings provided at least three trajectory h v points Additionally we review the importance of terminal heights and the way they have been estimated in previous studies Finally we discuss a new approach for calculating terminal heightsWe thank Eleanor Sansom for her valuable comments which helped to improve the content of this chapter Dr TrigoRodríguez and MMI acknowledge support from the Spanish Ministry of Sciences research project AYA201567175P MG and MMI were supported in part by the Academy of Finland project No 260027 MG was also supported by the Magnus Ehrnrooth Foundation travel grant and by the Russian Foundation for Basic Research project Nos 140800204 160500004 and 160701072 This study was done in the frame of a PhD on Physics at the Autonomous University of Barcelona UAB

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