Risks for Life on Proxima b from Sterilizing Impacts

TL;DR

This paper examines how a debris belt between Proxima b and c could increase impact risks, potentially sterilizing Proxima b, and discusses how future telescopes might detect such belts to assess habitability risks.

Contribution

It introduces a generalized model for impact rates on habitable planets influenced by asteroid belts and outer planets, with implications for assessing planetary habitability.

Findings

A debris belt could significantly increase impact rates on Proxima b.

Future telescopes like ALMA or JWST can detect asteroid belts that threaten habitability.

The impact rate model applies broadly to systems with asteroid belts and outer planets.

Abstract

We consider the implications that a debris belt located between Proxima b and Proxima c would pose for the rate of large asteroid impacts that could sterilize Proxima b from life. Future observations by ALMA or JWST could constrain the existence of an asteroid belt in the life-threatening regime. We generalize our rate calculation of sterilizing impacts for habitable planets in systems with an asteroid belt and an outer planet.