A curious chilly area of space may have been created when a parallel universe crashed into our own, scientists have suggested, the first evidence that we may be part of a multiverse.
In 2015, astrophysicists discovered a strange barren area of the universe which was much colder than the rest of space, and seemed to be missing 10,000 galaxies.
The ''Cold Spot'' which is 1.8 billion light-years across, is the largest known structure ever discovered, yet appeared to contain 20 per cent less matter than it should, and has baffled scientists since it was recorded.
But now experts Durham University have come up with a solution which is not only out of this world, but out of this universe.
They say that a parallel universe crashed into ours, causing a shunting action much like in a traffic accident when cars pile up on the motorway. The impact was so extreme that it pushed energy out of huge area of space, creating the Cold Spot.
Scientists now believe that if our universe ''ballooned up'' into a vacuum after The Big Bang, then trillions of others could also have formed in the same way, creating a multiverse of other universes beyond our own space-time.
The Cold Spot could be the first evidence of the multiverse.
Professor Tom Shanks in Durham University's Centre for Extragalactic Astronomy, said: "One explanation for the Cold Spot is that it might be the remnant signal of the collision of our universe and one of the trillions of others.
"If further, more detailed, analysis proves this to be the case then the Cold Spot might be taken as the first evidence for the multiverse and billions of other universes may exist like our own."
The Cold Spot is only about three billion light-years away from Earth, a relatively short distance in the cosmic scheme of things.
The whole universe is covered in cosmic microwave background (CMB), a relic of the Big Bang which can be detected by telescopes on Earth. But while the temperature of most of the CMB is 2.73 degrees above absolute zero (or -270.43C), the Cold Spot is about 0.00015 degrees colder than its surroundings.
Until the new research was published, most scientists thought the colder temperature in the space might be caused by a literal trick of the light.
They speculated that the colder area was actually a ''supervoid'' which had 10,000 fewer galaxies and was so barren that it sucked energy out of light travelling through it, shifting its wavelength it to the red end of the spectrum, which telescopes mistook for coldness.
But the Durham team found that the area actually is made up of clusters of smaller voids, all of which are too little to shift light enough for that explanation to work.
Doctoral student Ruari Mackenzie of Durham University added: "The voids we have detected cannot explain the Cold Spot."
Professor Shanks said there had to be another explanation. "Perhaps the most exciting explanation is that the Cold Spot was caused by collision between our universe and another bubble universe, believe it or not.
"I remember some scientists suggesting that there could be detectable effects on the galaxy distribution after this 'cosmic shunt' of two universes colliding.
"Basically colliding universes could leave a slightly anisotropic galaxy distribution in our own universe; a bit like a pile-up on the motorway. So we can look for this to test how seriously to take these ideas."
The results were published in Monthly Notices of the Royal Astronomical Society.
This story was originally published by The Daily Telegraph UK.