investigator have suspect that ripples in the outer disk of the Milky Way may have been created by a violent interaction in the past between our galaxy and one of its modest companions hundreds of trillion of years ago . Now , investigator think they have found that fellow traveler : Antlia 2.The study is published inarXiv .
The dwarf galaxy was only recently find thanks to the European Space Agency ’s Gaia satellite . Antlia 2has been describedas a “ trace of a galaxy ” because it is super diffuse . It is dim for its size and has the last surface brightness of any coltsfoot chance upon so far . It is almost as large as the biggest companion of the Milky Way , the Large Magellanic Cloud , but 10,000 sentence fainter .
Lead source Sukanya Chakrabarti performed dynamic simulations of our Galax urceolata in 2009 and predicted the location of a small galaxy dominated by dark matter that could have disrupted the Milky Way . Antlia 2 is stuffy to that location , so Chakrabarti and her squad consider it a prime suspect .
“ We do n’t understand what the nature of the dark matter particle is , but if you consider you know how much dark affair there is , then what ’s leave indeterminate is the mutation of denseness with radius , ” Chakrabarti , an adjunct prof from Rochester Institute of Technology , said in astatement . “ If Antlia 2 is the dwarf galaxy we auspicate , you do it what its area had to be . You be intimate it had to come nigh to the astronomical disc . That set stringent constraints , therefore , on not just on the mass , but also its denseness profile . That intend that ultimately you could utilise Antlia 2 as a singular science laboratory to memorise about the nature of glum thing . ”
The Gaia quad observatory is currently create a comprehensive3D mapping of 1000000000000 of ace in the Milky Wayand its neighboring wandflower . The researcher hope to realise more information about the apparent movement of stars within Antlia 2 in upcoming data released by Gaia so as to work out its distribution of matter ( both visible and sullen ) and whether or not the small galaxy really did smash through the Milky Way .
