Science Daily linked this horrendous agitprop from the Sloan Digital Sky Survey. Within it is the story, which is missing a lot of essential information. I'll deliver the story so you don't have to go to SDSS and get snowed.
SDSS J0715-7334 (those are co-ordinates) was reported as a red giant out 79,256 ly away, last October again; ScienceDaily / SDSS are reporting on its formal publication. It hosts ultra-low "metallicity", including a carbon footprint of "undetectable". This means it was formed by hydrogen and helium... only. Also its orbit is unnatural for the Milky Way today and, it seems, all those sub-galaxies which we have gobbled like the one in Exodus. SDSS and the University of Chicago conclude that it must have formed in that Large Magellanic Cloud (nebula, in Latin; galaxy, in reality) halo, back when there were no "metals". 163kly from us.
All this means this - sigh - immigrant
bears a time capsule from the founding matter of the LMC.
Initial reports were claiming 2900% solar mass. I find hard to believe that 30 solar-mass primordial red giants should still exist and, yes; later interviews have ratcheted that down. Rather, a 30 sol star - which must be almost the first star ever to exist in the LMC - went Type II supernova, nearly immediately as they would. This explosion from the implosion pushed still-thick hydrogen and helium gas into the star in question. Which was still heavier than us. It went red-giant somewhere on its journey to our own galaxy.
As to how it got here, rather to our own halo (the word "back yard" is getting used): that it was a secondary formation under high wind might have pushed it across our galaxies' mutual L1.
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