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The problem with that star, Suzy, is that it has such a low metals content that it's hard to see how such a star could've formed in the first place. Without going into the particulars of the mechanisms by which a gas cloud collapses to form a star, the dearth of metals within the cloud that formed this star would've normally made it very difficult for the cloud to collapse to form the star/stars in the first place....especially low mass stars like this one. With clouds that have such a low metals content, the clouds have a hard time trying to collapse because of the internal pressures generated by heating within the cloud. The presence of metals actually allows the cloud to radiate away that heat more efficiently than it would otherwise. The only way for metal deficient clouds to collapse is to build up mass, to a point that the instabilities within such clouds allows the gravity to collapse the clouds and form stars...which are usually much larger than they would normally otherwise be. That's why the early PopIII stars were so large because they formed from clouds of almost pure hydrogen and helium. Instead of many smaller stars forming from the clouds, the clouds collapsed and formed one or two very large stars...some of which may have weighed as much as 1000-2000 solar masses, possibly even more. Not only that, but nearly all of those stars were much hotter than today's stars. Because a cloud of almost pure hydrogen and helium is relatively transparent to radiation, in order for a star to be of a certain spectral class, it has to be hotter than it would be if it was like stars of today. Some of these giants in the beginning radiated at temps of around 250000-500000K and the largest of them were more than 1 billion times brighter than the Sun. They would've lasted only a few hundred thousand to a millions years or two before they all went hypernova and/or collapsed into black holes. The star they were talking about in the article isn't a PopIII star, despite its low metals content and age. It's more like what they call an extreme PopII star, much like the halo stars surrounding our galaxy, only with even less metals than what most of them have. It's more than likely one of the first stars that formed in the generation immediately proceeding the PopIII era, or very close to that time. There's bound to be more of these types of stars populating the halo and spread amongst the stars of the spiral. It's just a matter of time before than find them.
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