A giant supervoid 1.8 billion light-years across may be responsible for a mysterious ‘ Cold Spot ’ in the universe . The theory was proposed by astronomers seeking to understand what is causing this larger-than-expected cold area . If confirmed , the supervoid would be the largest single structure ever found by humanity . Hawaii scientists say a supervoid may account for an anomaly in the cosmic microwave background radiation ( CMB ) of the universe , shown bottom right . In 2004 astronomers first found the 'Cold Spot ' - a region 20 per cent less dense than elsewhere - and may now have an explanation for its formation . The research , published in Monthly Notices of the Royal Astronomical Society , was carried out by the Institute for Astronomy at the University of Hawaii at Manoa . The Cold Spot was first discovered by astronomers in 2004 when they were examining a map of the radiation left over from the Big Bang - the cosmic microwave background ( CMB ) - made using Esa 's Planck telescope . In the map , the universe is fairly evenly distributed , apart from in this one area . The huge unexpected region contains about 20 per cent less matter than other regions of the universe and about 10,000 less galaxies . While other sparse regions have been discovered , nothing on this scale has been found before . ‘ Statistically , we are very confident that the supervoid is there , ’ Dr András Kovács , who was involved in the study , told MailOnline . He said that the supervoid appears to be ‘ roughly spherical ’ , and it may even contain a ‘ significant substructure ’ at its centre ; a void within a void . A supervoid is not empty , but rather a region of space that has less matter than other parts of the universe . For this reason it can ‘ sap ’ the energy of light that is passing through it . To explain how that works , imagine the void to be a hill . As light enters the void and travels towards its middle , it can be said to be climbing the hill , using up energy . Once it passes the centre , it would begin ‘ descending ’ the hill and regain the energy it expended to get there . But as the universe is expanding , by the time the light gets to the centre , its route out has become ‘ shallower ’ - or less dense . This means it can not regain as much energy as it lost initially and leaves the void with less energy , therefore a longer wavelength , which corresponds to a colder temperature . The different is marginal - typically about 70 nano-Kelvins - but it is enough to stand out when the entire cosmic microwave background radiation ( CMB ) of the universe is measured . The supervoid is thought to be causing a 'less-dense ' region of the universe ( illustration of empty space shown ) . At 1.8 billion light-years across it would be the biggest object ever found . But some 'exotic physics ' is also needed to explain what 's happening . The huge unexpected Cold Spot region , shown , contains about 20 per cent less matter than other regions of the universe , and about 10,000 less galaxies . While other sparse regions have been discovered , nothing on this scale has been found before . The original theory was that the Cold Spot originated from the Big Bang , and was a rare sign of 'exotic physics ' that our current models of the universe could not explain . This new theory , however , suggests otherwise . Previous attempts to find a void at the distance of the Cold Spot were unsuccessful , but this latest study suggests it is actually a foreground object , three billion light-years from Earth . According to lead researcher Dr Istvan Szapudi , the object - if confirmed - would be ‘ the largest individual structure ever identified by humanity. ’ The team gathered data using Hawaii ’ s Pan-Starrs1 ( PS1 ) telescope on Haleakala , Maui , and Nasa ’ s Wide Field Survey Explorer ( Wise ) satellite . The findings by the researchers were made using Nasa ’ s orbiting Wide-Field Infrared Survey Explorer ( Wise ) telescope ( artist 's illustration shown ) , which was launched on 14 December 2009 , and Hawaii ’ s Pan-Starrs1 ( PS1 ) telescope on Haleakala , Maui . However , the supervoid can only account for about half of the entire Cold Spot , suggesting there might still be some exotic physics at play . The researchers note , though , that it is ‘ very unlikely ’ that the supervoid and the Cold Spot being in the same location are a coincidence . They are continuing to study the void with improved data from PS1 , and from the Dark Energy Survey being conducted with the Cerro Tololo Inter-American Observatory in Chile .
Hawaii scientists say a supervoid may account for a cosmic anomaly . The object is thought to be causing a 'less-dense ' region of the universe . At 1.8 billion light-years across it would be the biggest object ever found . Comment: