Could a nearby supernova trigger a mass extinction on Earth?
The death of a massive star is a beautiful, violent event, but it also releases deadly radiation. This video explores the distance required for a supernova to remain safe and examines how these cosmic explosions may have historically devastated life on our planet.
New research suggests that at least two mass extinction events in Earth's history—the Ordovician and the late Devonian—may have been caused by nearby supernovae. These explosions could have stripped away the ozone layer, triggered acid rain, and exposed life to intense ultraviolet radiation. The Ordovician event, occurring 445 million years ago, wiped out 60 per cent of marine invertebrates, while the late Devonian, 372 million years ago, destroyed roughly 70 per cent of all species.
While supernovae act as creators by spreading the heavy elements necessary for new planets and life, they also act as destroyers. By analyzing the distribution of OB stars within a kiloparsec (approximately 3,260 light-years) of the Sun, researchers found that the frequency of such explosions near Earth is consistent with the timing of these ancient extinctions.
Source: What Supernova Distance Would Trigger Mass Extinction?
