Gamma Ray Bursts Effects on Extinction and Survivability in the Galaxy

TL;DR

This paper explores how Gamma Ray Bursts may influence the evolution and extinction of complex life in the galaxy, acting as a filter that limits advanced life development especially near the galactic center.

Contribution

It introduces a model linking GRB frequency to evolutionary milestones, suggesting GRBs can reset biological progress and impact the distribution of complex life in the galaxy.

Findings

GRBs can cause ozone depletion leading to increased UV exposure.

Resilient extremophiles may survive intense GRBs, but complex life is vulnerable.

GRBs are more likely to inhibit advanced life emergence near the galactic center.

Abstract

High-energy astrophysical events, particularly Gamma Ray Bursts (GRBs), have been proposed as significant contributors to mass extinction events on Earth-like planets in most of the galaxy, internal to our radius in it. This paper examines the extent to which GRBs may reset the evolutionary progress of complex life through repeated extinction-level disruptions. While resilient extremophiles may survive even the most intense GRBs, more complex surface-dwelling organisms are vulnerable to indirect atmospheric effects, primarily UV exposure following ozone depletion. By identifying evolutionary milestones and estimating how frequently GRBs would need to occur to prevent recovery between such milestones, this work proposes that GRBs could act as evolutionary filters, limiting the emergence of advanced life, but only much closer to the galactic center. We consider the implications for searches of various biosignatures versus technosignatures.