Risks for Life on Proxima b from Sterilizing Impacts

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.