Scientists have long wondered about cosmic events that can affect our planet’s biology. A new study from Keele University suggests that powerful stellar explosions could be tied to catastrophic shifts in Earth’s distant past.
Researchers found a match between the rate of massive star supernovas near Earth and two ancient losses of life, known as the late Devonian and Ordovician events. These events occurred 372 million years ago and 445 million years ago, respectively, and led to significant changes in aquatic life and marine invertebrates.
The study proposes that a nearby supernova may have stripped away the ozone layer, allowing intense ultraviolet light to reach Earth’s surface, leading to acid rain, and exposing organisms to harmful solar radiation. The team calculated the supernova rate near Earth and found it consistent with major extinction events linked to external triggers.
While the findings are intriguing, experts note that there are still many unanswered questions, such as how quickly the atmosphere recovers from increased solar radiation and whether life on land reacts differently when cosmic rays increase. However, the study provides a potential explanation for ancient tragedies, pointing to a story where Earth’s history may have been influenced by cosmic events.
Source: https://www.earth.com/news/at-least-two-of-earths-mass-extinctions-caused-by-massive-supernova-explosions