Sure, we all know about the asteroid impact that is thought to have wiped out the dinosaurs, but did you know that the Earth has seen other, widely-destructive mass-extinction events?

And astonishingly, these events predate even the dinosaurs.

That’s according to researchers at Keele University in the UK, whose recent study has been published by the Royal Astronomical Society.

According to a Keele University statement, these two mass-extinction events (known as the late Devonian and Ordovician extinction events) were a result of massive nearby supernova explosions.

The explosions (which took place 372 and 445 million years ago) are thought to have killed between 60 and 70 per cent of the Earth’s creatures for some key atmospheric reasons.

Firstly, the researchers suggest, the blasts from the expiring stars caused the atmosphere to lose its ozone, with huge consequences.

Not only was there a huge amount of acid rain that ultimately acidified the oceans in which the majority of creatures lived, the change in the atmosphere also exposed our planet to hugely increased amount of ultraviolet radiation, as the study’s lead author, Dr Alexis Quintana, explained in the statement:

“Supernova explosions bring heavy chemical elements into the interstellar medium, which are then used to form new stars and planets.

But if a planet, including the Earth, is located too close to this kind of event, this can have devastating effects.”

And the team’s research answered long-held questions both about the stars around us, as well as about the cause of these two lesser-known mass extinction events.

By calculating the rate of supernovas on our galaxy, the research team contributed to our greater understanding of what happens in the event of a supernova, as well as how such events might occur again in our future, as Keele University’s Dr Nick Wright continued:

“Supernova explosions are some of the most energetic explosions in the universe.

If a massive star were to explode as a supernova close to the Earth, the results would be devastating for life on Earth. This research suggests that this may have already happened.”

The bad news? One or two supernovas occur every century.

The good news? The only two stars close to us that are likely to go into supernova in the next million years are over 500 light-years away, meaning that there’s no chance of a supernova-triggered mass-extinction event in our near future.

If you thought that was interesting, you might like to read about a second giant hole has opened up on the sun’s surface. Here’s what it means.