Nearby Supernovae Linked to Two Ancient Mass Extinctions on Earth

New research suggests supernova explosions may have caused ozone depletion, driving extinction events in the Ordovician and Devonian periods.

Astrophysicists from Keele University have linked two of Earth's mass extinctions to nearby supernova explosions.
The study highlights the Ordovician extinction 445 million years ago and the Devonian extinction 372 million years ago as possible consequences of ozone layer depletion caused by supernovae.
Supernovae within 65 light-years of Earth could strip the ozone layer, exposing life to harmful ultraviolet radiation and triggering environmental collapse.
Researchers calculated a supernova rate consistent with the timeline of extinction events, though direct evidence such as radioactive isotopes is unavailable due to their decay over time.
The findings emphasize the dual role of massive stars in fostering life by creating heavy elements and potentially destroying it through catastrophic explosions.