Supernova’s and Mass Extinction
The stars around us are moving around the galaxy at slightly different orbits to that of our own, so even a million years ago, the stars in our night sky would have looked very different indeed, as they will look different in the future.
The difference isn’t just a matter of pretty constellation patterns though, nor even which is the brightest or closest, very large stars 20+ times the mass of our sun when they come to the end of their lives, blow up as a supernova, and so when one of these giant stars comes near to Earth (within 100 light years), it’s a potential existential hazard for life on Earth.
One such possible event occurred at the end of the Devonian period around 360 million years ago, a mass extinction that has the hallmarks of a ozone layer collapse and irradiation event. Evidence for a local supernova is building, but there is no doubt any such event that aligned the poles such that they pointed towards us, would cause serious damage to the Earth’s ecosystem.
Source : https://astronomynow.com/2020/08/24/nearby-supernova-blasts-may-be-culprits-in-at-least-one-mass-extinction/
