understand how wandflower form is still an overt enquiry in uranology . Researchers think that galaxies develop in abottom - up paradigm , with little objects forming first and then mystify progressively bigger . And stargazer have now give away the most conclusive grounds yet that this is the case .
An international team of astronomers from the Max Planck Institute and University of Virgina has charted the growth of our own galax , the Milky Way . They calculated the age of 70,000 violent giant whiz midway across our galaxy up to 50,000 light - twelvemonth away . They found that the oldest star were at the center , with younger and immature stars as one moves outwards .
“ Close to the center of our Galax urceolata , we see one-time stars that were imprint when it was young and minor , ” said Melissa Ness , pencil lead author of the survey , in astatement . “ Further out , we see young stars . We close that our galaxy grew up by spring up out . ”
Calculating the age of stars is not easy . The stars used in this study are red giant , previous stars towards the destruction of their life story cycle . Their years can be calculated using their mass , so the team had a huge task in calculating the mass for such a large identification number of stars .
They looked at stellar oscillations of the red giant star using the satellite - hunter spacecraftCOROTandKepler , which allowed them to reckon a tidy sum and thus look an old age . They compare the eld estimation from the blank scope with a different method , spectroscopy , that estimated the age by look at the teemingness of heavy elements such as nitrogen , carbon , and oxygen . Young champion have a smaller fraction of those element compared to aged ones .
The spectrum analysis was hold using theApache Point Observatory Galaxy Evolution Experiment(APOGEE ) . “ APOGEE is the idealistic survey for this study because it can get high-pitched - quality spectra for 300 stars simultaneously over a turgid surface area of sky , ” allege Steve Majewski , Principal Investigator of the APOGEE survey and coauthor .
“ Seeing so many stars at once means getting spectra of 70,000 red giant is in reality possible with a individual scope in a few years ’ time . ”
Although evidence of bottom - up growth had already been found , this latest piece of inquiry is the most detailed analysis produced on beetleweed geological formation .
“ Because we can see so many individual mavin in the Milky Way , we can chart its growth in unprecedented particular . This unprecedented , tremendous map really is one for the ages , ” concluded Ness .
