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 ≳1mm 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 ≲10−4s would be capable of detecting ≳1mm sub-relativistic meteors.
@article{arxiv.2002.01476,
title = {Observational Signatures of Sub-Relativistic Meteors},
author = {Amir Siraj and Abraham Loeb},
journal= {arXiv preprint arXiv:2002.01476},
year = {2020}
}