Hypothesis: Muon Radiation Dose and Marine Megafaunal Extinction at the End-Pliocene Supernova

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.

r-Process Radioisotopes from Near-Earth Supernovae and Kilonovae

“…as derived from the sediment data of Wallner et al (2016) and Ludwig et al (2016), where core 4953 of Wallner et al (2016) is the earliest 60 Fe detection. The peak of the 60 Fe deposition on Earth due to this event was ∼ 2.5 Mya, around the end of the Pliocene epoch, and a linkage to a coincident mass extinction has been proposed in Melott et al (2019). We note also that the ferromanganese crust data from Wallner et al (2016) provides evidence of a potential second peak at about 7 Mya that has yet to be confirmed in sediment data or in other studies.…”

Exploring the link between star and planet formation with Ariel

“…Extinct 60 Fe has been detected in the ocean crust, falling through Earth's atmosphere and oceans about 2.2 million years ago (e.g., [211]). This has been connected with a mass extinction event affecting many species in our oceans about 2.6 million years ago, due to the radiation from the same nearby supernova (e.g., [212]). This makes really hard to define what is the correct amount of 26 Al and 60 Fe to use in simulations of planet formation.…”

Exploring the link between star and planet formation with Ariel

“…Extinct 60 Fe has been detected in the ocean crust, falling through Earth's atmosphere and oceans about 2.2 million years ago (e.g., Ludwig et al, 2016). This has been connected with a mass extinction event affecting many species in our oceans about 2.6 million years ago, due to the radiation from the same nearby supernova (e.g., Melott et al, 2019). This makes really hard to define what is the correct amount of 26 Al and 60 Fe to use in simulations of planet formation.…”