uranologist have model the move of stars in century of galaxies in the local universe and they are using this valuable resource to better infer how these objects evolved since their formation 1000000000 of years ago .
As reported inNature Astronomy , an external team of researchers looked at 300 nearby galaxy from theCALIFA(Calar Alto Legacy Integral Field Area ) survey – a project using the Calar Alto scope in Spain – and from the study , were able-bodied to work out if the star were moving in regular settled electron orbit or in a more chaotic way . By observing the star ' orbits they could " read " the story of the galax .
All stars in every galaxy are moving in multiple unlike ways , but by comparing how many star are experience each character of motion , astronomers can redo what galaxies have experienced in the yesteryear . A galaxy fusion , for deterrent example , would lead to a more quicksilver motion of stars while a orbitual orbit indicates a more calm story . Being able to work out the orbit of stars is not square though . We can work out the motility for many stars inside our own Galax urceolata but when it come to galaxies millions of promiscuous - years away , this approach path is not feasible .
“ The motion of every individual star is not directly observable in outside coltsfoot . External galaxies are projected on the observational plane as an range of a function and we can not decide the discrete headliner in it , ” lead source Ling Zhu , from the Max Planck Institute for Astronomy , say in astatement . “ The CALIFA survey use a of late evolve technique , integral field spectrographic analysis , which can observe the outside extragalactic nebula in such a means that it allow for the overall motion of adept . Thus , we can get kinematic maps of each extragalactic nebula . ”
As stars move , their visible brightness level can beblue - shifted or reddish - shifteddepending if they are follow toward us or go away from us . This fracture , called theDoppler burden , is mensurable and the CALIFA survey is capable of doing so in multiple region of each galax . This is the base for the kinematic maps that the squad has produced .
The squad was capable to show a clear human relationship between mass and case of area . They discovered that galaxies that have about 10 billion solar slew worth of stars incline to be dominated by the more ordered orbits , while much big galaxy have more helter-skelter orbit . This severally confirms an expected value in galaxy evolution . Bigger galaxies have increased their sizing through unification so they must have more chaotic scope .
“ This is the first orbit - based mint sequence across all morphological types , " add co - author Glenn van de Ven , constitute the European Southern Observatory . " It include flourishing information of a wandflower ’s past times , essentially whether it had been a hushed succession of only modest mergers or determine by a violent major amalgamation . Further field of study are postulate to infer the inside information . ”
This new direction of reading the account of galaxy could be very utile for testing against cosmogonic simulations of galaxies .
