Dynamical and biological panspermia constraints within multi-planet exosystems

TL;DR

This paper develops analytical tools to evaluate the likelihood of life transfer within multi-planet systems, considering impact processes, debris transport, and microorganism survival, aiding the understanding of panspermia in exoplanetary systems.

Contribution

It introduces algebraic prescriptions for impact-driven panspermia processes, providing a unified framework to assess intra-system life transfer without complex differential equations.

Findings

Derived probability distribution for debris reaching planetary orbits

Quantified microorganism survival during ejection and transit

Provided impact characteristics necessary for panspermia

Abstract

As discoveries of multiple planets in the habitable zone of their parent star mount, developing analytical techniques to quantify extrasolar intra-system panspermia will become increasingly important. Here, we provide user-friendly prescriptions that describe the asteroid impact characteristics which would be necessary to transport life both inwards and outwards within these systems within a single framework. Our focus is on projectile generation and delivery and our expressions are algebraic, eliminating the need for the solution of differential equations. We derive a probability distribution function for life-bearing debris to reach a planetary orbit, and describe the survival of micro-organisms during planetary ejection, their journey through interplanetary space, and atmospheric entry.