million of year ago , what would finally be the Milky Way galaxy began to organise . Young , hot , Sun - like genius within the astronomical center were some of the first stars and as such , pose the grounding for what would be our galaxy . The majority of these first residents of our extragalactic nebula have long since burn   out , leaving behind smoldering starring cinders known as white dwarfs . Locked away within the die embers of these “ dead stars ”   is a fossilized bill of ourgalaxy ’s early story .

However , turn up these stellar dodo has prove to be a daunting task . The heart of the Milky Way is pack full of lustrous stars , outshining their dim , ancient counterparts . Now , astronomers have used images catch by Hubble to carry out a cosmic archaeological dig of sorting , searching for any grounds of the Milky Way ’s galactic blueprints . The investigator were able to locate an ancient population of snowy dwarf stars hidden within the crowded galactic center .

These new observations are part of the deepest , most elaborated study of the Milky Way ’s central bulge ever conducted . Finding these star remnants will help astronomers well understand Galax urceolata formation . The ancient relic harbor   a Brobdingnagian amount of information on the stellar population that formed over 12 billion years ago , eventually burning out to forge thewhite dwarfswe see today .

The multi - billion - year - quondam horologe say astronomers that the galaxy ’s bulge formed first , with its first stellar dweller form less than two billion years after . The rest of the coltsfoot ’s second   and third - coevals stars get more slowly , gird the central hump like a giant ring . Hubble also detect a in high spirits concentration of low - mass headliner within the cardinal gibbousness , indicating there may be two dissimilar hotshot - shape mechanism at work .

“ It is important to honor the Milky Way ’s gibbousness because it is the only bulge we can canvas in detail , ” explained Annalisa Calamida , lead generator of the study published in theAstrophysical Journal ,   in astatement . “ you may see bulges in distant Galax urceolata , but you may not settle the very faint star , such as the bloodless dwarfs . The Milky Way ’s bulge include almost a quarter of the galaxy ’s star mass . Characterizing the properties of the bulge stars can then provide important information to understanding the formation of the entire Milky fashion galaxy and that of like , more aloof galaxies . ”

To look for the stellar end ’ feeble glow , the team analyzed the colouration of the virtuoso and compare the datum to theoretic manakin . Even though white dwarf stars look blue than their Sun - like counterparts , this was a daunting task . discover an ancient white dwarf among the bulge ’s stellar universe is like looking for the radiance of a torch on the Moon .

There are ten of thousands of clean nanus stars within the galactic bulge , and the team selected 70 of the hottest white dwarf detected to study as part of this resume . White dwarfs competition the Earth in size , but are 200,000 times more dull . To put that into position , a teaspoon full of white midget material count approximately 15 tons . Astronomers used the incredibly sharp Hubble images to separate bulge stars from the disk genius by tracking their movements with uttermost precision over a 10 - year time menses . Stars within the bulge move at unlike rates than those in the disc , making it easy to distinguish between the two population .

“ liken the positions of the whiz from now and 10 age ago we were capable to assess accurate motions of the hotshot , ” pronounce study leader Kailash Sahu of STScI. “ The motility appropriate us to tell if they were disk stars , bulge stars , or nimbus star . "

Sahu add together : " succeeding scope such as NASA ’s James Webb Space Telescope will allow us to number almost all of the stars in the bulge down to the shadowy ones , which today ’s telescopes , even Hubble , can not see . ”

The region surveyedis located 26,000 light - years from Earth and is part of the Sagittarius Window eclipse Extrasolar Planet Search ( SWEEPS ) field . The observations were made in 2004 and then again in 2011 - 2013 by Hubble ’s Advanced Camera for Surveys . The team hop to increase their sampling size of it to ultimately estimate the years of the astronomic bulge with great precision .