Impact of Nearby Supernova Shockwaves on Cosmic Ray Irradiation of Earth's Organisms

Recent research has highlighted a significant increase in cosmic ray irradiation of organisms on Earth, attributed to shockwaves from nearby supernovae (SN). The study, titled "Sharp Rise in Cosmic Ray Irradiation of Organisms on Earth Caused by a Nearby SN Shockwave Passage," was conducted by authors A.A. Shchepkin, G.I. Vasilyev, V.M. Ostryakov, and A.K. Pavlov. It explores how cosmic rays (CRs) accelerated by supernova shockwaves affect the Earth's biosphere.

The researchers modeled the effects of nearby supernovae on cosmic ray flux, noting that the radiation background on Earth rises sharply when a shockwave crosses the Solar System. This increase in cosmic rays leads to heightened external irradiation from high-energy particles and internal radiation due to the decay of cosmogenic carbon-14 (14C).

Key findings from the simulations indicate:

• A significant rise in external ionization at the Earth's surface, with atmospheric cascade particles penetrating depths of 70-100 meters in water.
• The decay of 14C has the potential to irradiate not only surface organisms but also deep ocean life.
• An analysis of mutation rates suggests that the distance from Earth to a supernova, where lethal effects from irradiation could occur, is approximately 18 parsecs for supernovae with an energy output around 10^51 ergs.

These findings raise concerns about the potential biological impacts of cosmic radiation on Earth's ecosystems, particularly in the context of increased mutation rates and the health of various organisms. The study emphasizes the need for further research into the long-term effects of cosmic ray exposure on life on Earth. The full paper can be accessed through arXiv at arXiv:2409.00288.