Observational Signatures of Sub-Relativistic Meteors

Amir Siraj; Abraham Loeb

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arXiv · 2002.01476

Observational Signatures of Sub-Relativistic Meteors

Amir Siraj·Abraham Loeb

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Abstract

It is currently unknown whether solid particles larger than dust from supernova ejecta rain down on Earth at high speeds. We develop a hydrodynamic and radiative model to explore the detectability of $\gtrsim 1 \mathrm{\; mm}$ sub-relativistic meteors. We find that a large fraction of the meteor energy during its passage through the Earth's upper atmosphere powers the adiabatic expansion of a hot plasma cylinder, giving rise to acoustic shocks detectable by infrasound microphones. Additionally, a global network of several hundred all-sky optical cameras with a time resolution of $\lesssim 10^{-4} \mathrm{\;s}$ would be capable of detecting $\gtrsim 1 \mathrm{\; mm}$ sub-relativistic meteors.

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Amir Siraj, Abraham Loeb. 2020-02-04. Observational Signatures of Sub-Relativistic Meteors. https://arxiv.org/abs/2002.01476

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