saturnine matter is the hypothetical substance that cocoons galaxies and outweighs even matter in the macrocosm five to one . We ca n’t directly honor it because it does n’t interact with light but we can measure its gravitational effect , which is how we “ see ” it , especially by await at the question of galaxies and clusters of galaxies .
research worker have report a new approach that better how we estimate , or " see " , the presence of sullen matter . As describe in theMonthly Notices of the Royal Astronomical Society , this method uses gravitational lensing . The gravity of massive objects warp space - time in such a way that any distant lightheaded source behind it appears to the observer as though through an optical lens .
The effect used in this specific written report is known as decrepit gravitational lensing . In this suit , the shape and size of it of distant galaxies are only slightly altered .
“ The morose matter will very slightly tinge the double of anything behind it , ” explain Associate Professor Edward Taylor in astatement . “ The issue is a bit like read a newspaper through the floor of a wine trash . ”
Detecting these changes requires high - precision observance but leads to very detailed maps of dark subject .
“ It ’s like looking at a flag to try out to get laid how much wind there is . you could not see the wind , but the flag ’s motion narrate you how strongly the breaking wind is muff , ” leash source Pol Gurri , a graduate research worker from the Swinburne University of Technology , added .
The team go a step further than standard weak gravitational lensing , however . The new approach used the ANU 2.3 molarity Telescope in Australia to measure the rotational pep pill of gravitationally lensed galaxy . This provides an even more precise view of the distortion , in turn allowing the squad to work out a more graceful estimation of how much colored issue must be present in the foreground to create the lensing event seen .
“ Because we know how whiz and gas are opine to move inside galaxies , we know rough what that Galax urceolata should look like . By measure how distorted the tangible Galax urceolata double are , then we can figure out how much dark matter it would take to explain what we see . said Gurri . " With our new direction of seeing the dark affair , we desire to get a clearer picture of where the dark issue is , and what role it play in how galaxy form . ”
Future foreign mission such as NASA’sNancy Grace Roman Space Telescopeand ESA’sEuclid Space Telescopeare expect to carry out these observance for hundreds of 1000000 of extragalactic nebula .
