7:09PM BST 20 Apr 2015
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Astronomers have discovered a curious empty section of space which is missing around 10,000 galaxies.
The ‘supervoid’, which is 1.8 billion light-years across, is the largest known structure ever discovered in the universe but scientists are baffled about what it is and why it is so barren.
It sits in a region of space which is much colder than other parts of the universe and although it is not a vacuum, it seems to have around 20 per cent less matter than other regions.
Although the Big Bang theory allows for areas that are cooler and hotter, the size of the void does not fit with predicted models. Simply put, it is too big to exist.
István Szapudi, of University of Hawaii at Manoa, described the object as possibly “the largest individual structure ever identified by humanity”.
It was picked up using Hawaii’s Pan-STARRS1 (PS1) telescope located on Haleakala, Maui, and Nasa’s Wide Field Survey Explorer (WISE) satellite.
The latest study suggests that the ‘supervoid’ may be draining energy from light travelling through, which is why the area around it is so cold.
Getting through such a big hole takes hundreds of millions of years, even at the speed of light, and photons of light slow down as they cross because the universe – and therefore the void - is continually expanding.
However the scientists claim that the void can only account for around 10 per cent the temperature drop in the cold spot.
“It just pushed the explanation one layer deeper,” said Dr Roberto Trotta, a cosmologist at Imperial College London.
The supervoid is only about 3 billion light-years away from Earth, a relatively short distance in the cosmic scheme of things.
“Supervoids are not entirely empty, they’re under-dense,” said András Kovács, a co-author at the Eötvös Loránd University in Budapest.
“This is the greatest supervoid ever discovered. Given the combination of size and emptiness, our supervoid is still a very rare event. We can only expect a few supervoids this big in the observable universe.”
The researchers report their findings in the journal Monthly Notices of the Royal Astronomical Society.
