HUNDREDS of giant comets hurtling through space could crash into Earth at ANY MOMENT wiping out every living species.
Scientists today warned the belt of so-called 60 mile-wide ‘Centaurs’ could trigger a mass extinction event.
If one is deflected towards Earth it will break up on approach releasing hundreds of ‘fireballs’ into the atmosphere, they warn.
It would lead to mass devastation with the resulting dust could plunging the Earth into a decade-long winter.
With sunlight all but completely blocked, temperatures would plunge below freezing across the planet - known as an ‘impact winter’.
New research released by Armagh Observatory and the University of Buckingham say comets pose a much greater danger to life than asteroids.
They say such an impact could have been responsible for the death of the dinosaurs 65 million years ago.
The research published in this month’s Royal Astronomical Society journal of Astronomy and Geophysics warns of a “serious hazard”.
Co-author Professor Bill Napier, of the University of Buckingham, said: “In the last three decades we have invested a lot of effort in tracking and analysing the risk of a collision between the Earth and an asteroid.
“Our work suggests we need to look beyond our immediate neighbourhood too, and look out beyond the orbit of Jupiter to find Centaurs.
“If we are right, then these distant comets could be a serious hazard, and it’s time to understand them better.”
Centaur comets are usually between 31 and 62 miles wide and travel at around 150,000 miles an hour.
Experts say they could be the cause of destruction of civilisations through history with events in 10,800 BCE and 2,300 BCE (before the common era) blamed on the colossal shooting stars.
Professor Napier said ‘Centaurs’ which are objects curling in very unstable orbits pose a much greater risk than more familiar comets.
He said although the chance of a direct hit - which would be nothing short of catastrophic - is slim, there is a risk of impact from debris as they break up.
He said hundreds of deadly missiles would burst into flame showering the Earth with deadly fireballs.
A cloud of dust blocking the sun would take around 10 years to settle bringing global Arctic conditions for a decade.
He said: “What we are worried about is the impact from fragments as the comets break up while heading towards the planet.
“This could generate hundreds of fireballs but the most serious impact would be from the subsequent dust which could block out the sun for a decade as it settles.
“The Earth would be thrown into a deep freeze.”
He said if a comet did not break up, it would be the end of life on Earth with every species in the planet wiped out.
“It would sterilise the planet,” he added, “and that would be the end of it.
"Some of the greatest mass extinctions in the distant past, for example the death of the dinosaurs 65 million years ago, may similarly be associated with this giant comet hypothesis.”
The impact would eclipse the devastating 1908 Tunguska Event which saw a 50-metre wide asteroid crash into Siberia.
It flattened around 80 million trees and sent a shock wave across Russia measuring five on the Richter scale.
The event is held by scientists as a benchmark for the catastrophic consequence of an asteroid impact with earth.
Professor Napier said samples from historic sites of mass destruction reveal fragments of glass which show silica particles were heated to extreme temperatures.
He said this is further proof that impact from comets could have been the cause of the destruction.
He added: “Any one of these comets could break up releasing debris which would rival the devastating Tunguska event.
“The frequency of how often they happen is a matter for much debate, but we are sure now that previous major collisions with Earth resulted in major catastrophic events.”