Andromeda is the nearest major galaxy to the Milky Way and for a long time , it has been considered the freehanded sib of our own galaxy . New research suggests that view might be wrong .
consort to Australian investigator , the Milky Way and Andromeda appear to have or so the same passel , which is estimated to be around 800 billion Suns . The new estimation was possible thanks to high - precision measurements of the escape speed of Andromeda , which allow them to work out out just how heavy our neighbour is . The study is published in theMonthly Notices of the Royal Astronomical Society .
“ When a rocket is launched into outer space , it is thrown out with a speed of 11km / s to overcome the Earth ’s gravitative pull , ” lead generator Dr Prajwal Kafle , from the International Centre for Radio Astronomy Research at the University of Western Australia , said in astatement . “ Our dwelling house galaxy , the Milky Way , is over a trillion times heavy than our tiny planet Earth so to escape its gravitative puff we have to launch with a fastness of 550km / s. We used this technique to tie down the the great unwashed of Andromeda . ”
Dr Kafle did utilize the same approach in 2014 to constrain themass of the Milky Wa , and , in that case , the great deal was revised down from the previous estimates . In both cause , the researchers were able-bodied to realize a wad more about galaxy than the mass alone .
“ By examining the orbits of high - pep pill stars , we discover that this galaxy has far less dark matter than previously thought , and only a third of that uncovered in previous observations , ” he explained .
The Milky Way and Andromeda are the largest members of the Local Group , the corner of the universe where we inhabit . The future of the two galaxies is also powerfully link . They will merge into a unmarried objective over the next 5 billion years . This new idea change how that hit will pan out .
“ It completely transform our understanding of the local group . We had thought there was one self-aggrandising galaxy and our own milklike Way was slightly smaller but that scenario has now wholly modify , ” Dr Kafle explicate . “ It ’s really exciting that we ’ve been capable to come up with a Modern method acting and of a sudden 50 years of collective sympathy of the local group has been turned on its head . ”
There is significant public debate to the right mass of both galaxies , but the new estimate has a small uncertainty compared to former measurements . This makes a very strong eccentric for a lighter Andromeda than antecedently thought .
