Exporting Terrestrial Life Out of the Solar System with Gravitational Slingshots of Earthgrazing Bodies

Abstract: Exporting terrestrial life out of the Solar System requires a process that both embeds microbes in boulders and ejects those boulders out of the Solar System. We explore the possibility that Earthgrazing long-period comets and interstellar objects could export life from Earth by collecting microbes from the atmosphere and receiving a gravitational slingshot effect from the Earth. We estimate the total number of exportation events over the lifetime of the Earth to be $\sim 1 - 10$ for long-period comets and $\sim 1 - 50$ for interstellar objects. If life existed above an altitude of 100 km, then the number is dramatically increased up to $\sim 10^5$ exportation events over Earth's lifetime.