Muon Radiation Dose and Marine Megafaunal Extinction at the end-Pliocene Supernova

TL;DR

This study models the increased muon radiation from a supernova 2.6 million years ago, suggesting it could have contributed to marine megafaunal extinction by exposing ocean depths to lethal radiation levels.

Contribution

It extends previous supernova radiation models by calculating muon flux penetration into ocean depths, linking astrophysical events to marine extinction events.

Findings

Muon radiation dose exceeded present surface levels up to 1 km depth.

Radiation persisted for at least the lifespan of marine megafauna.

Potential link between supernova-induced radiation and marine extinction.

Abstract

Considerable data and analysis support the detection of one or more supernovae at a distance of about 50 pc, ~2.6 million years ago. This is possibly related to the extinction event around that time and is a member of a series of explosions which formed the Local Bubble in the interstellar medium. We build on previous work, and propagate the muon flux from supernova-initiated cosmic rays from the surface to the depths of the ocean. We find that the radiation dose from the muons will exceed the total present surface dose from all sources at depths up to a kilometer and will persist for at least the lifetime of marine megafauna. It is reasonable to hypothesize that this increase in radiation load may have contributed to a newly documented marine megafaunal extinction at that time.