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arXiv · 1502.01898

New methodology to determine the terminal height of a fireball

Abstract

Despite ablation and drag processes associated with atmospheric entry of meteoroids were a subject of intensive study over the last century, little attention was devoted to interpret the observed fireball terminal height. This is a key parameter because it not only depends on the initial mass, but also on the bulk physical properties of the meteoroids and hence of their ability to ablate in the atmosphere. In this work we have developed a new approach that is tested using the fireball terminal heights observed by the Meteorite Observation and Recovery Project operated in Canada between 1970-1985 (hereafter referred as MORP). We then compare them to the calculation made. Our results clearly show that the new methodology is able to forecast the degree of deepening of meteoroids in the Earth's atmosphere. Then, this approach has important applications in predicting the impact hazard from cm- to meter-sized bodies that are represented, in part, in the MORP bolide list.

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Manuel Moreno-Ibáñez, Maria Gritsevich, Josep M. Trigo-Rodríguez. 2015-02-06. New methodology to determine the terminal height of a fireball. https://doi.org/10.1016/j.icarus.2014.12.027

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