Our planet’s first known mass extinction happened about 440 million years ago. Species diversity on Earth had been increasing ...

They believe a supernova explosion close to Earth could be to blame for both the late Devonian and Ordovician extinction events, which occurred 372 and 445 million years ago respectively.

For decades scientists have dubbed several of our planet's largest mass extinction ... Late Devonian (372-359 million years ...

Instead, the team hypothesized a stellar explosion may have been a potential factor in the Late Devonian extinction event 372 million years ago and one at the end of the Late Ordovician 445 ...