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arXiv · 1910.06414

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

Amir Siraj·Abraham Loeb
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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.

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Amir Siraj, Abraham Loeb. 2019-10-14. Exporting Terrestrial Life Out of the Solar System with Gravitational Slingshots of Earthgrazing Bodies. https://doi.org/10.1017/s1473550419000314

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