Probing Extrasolar Planetary Systems with Interstellar Meteors

Abstract

The first interstellar object, `Oumuamua, was discovered in the Solar System by Pan-STARRS in 2017, allowing for a calibration of the impact rate of interstellar meteors of its size $\sim 100\;$m. The discovery of CNEOS 2014-01-08 allowed for a calibration of the impact rate of interstellar meteors of its size $\sim 1\;$m. Analysis of interstellar dust grains have allowed for calibrations of the impact rate of smaller interstellar meteors down to the size $\sim 10^{-8}\;$m. We analyze the size distribution of interstellar meteors, finding that for smooth power-law fits of the form $N(r)\propto r^{-q}$, the possible values of $q$ are in the range $3.41 \pm 0.17$. We then consider the possibility of analyzing interstellar meteors to learn about their parent planetary systems. We propose a strategy for determining the orbits and chemical compositions of interstellar meteors, using a network of $\sim 600$ all-sky camera systems to track and conduct remote spectroscopy on meteors larger than $\sim 5$cm once every few years. It should also be possible to retrieve meteorites from the impact sites, providing the first samples of materials from other planetary systems.