LAP1-B: Next Candidate for Galaxy of First-Generation Stars
According to simulations, stars of the so-called Population III were massive and short-lived. Now there is another candidate for a galaxy composed of such stars.
Artist's impression of the James Webb Space Telescope
(Image: NASA-GSFC, Adriana M. Gutierrez (CI Lab))
In data from the James Webb Space Telescope, a research group from the USA has again found traces that could originate from stars of the very first generation. This is reported by the University of Toledo in the US state of Ohio. A galaxy designated LAP1-B, according to the report, meets three central predictions for stars of this Population III, but confirmation is still pending. In simulations of the universe, exactly such galaxies composed of these very first stars have emerged, as the state-of-the-art instrument has found them. The galaxy was thus seen in a state it assumed less than a billion years after the Big Bang.
So far only described theoretically
Population III refers to the first generation of stars, which consisted only of the light elements hydrogen and helium available after the Big Bang, as well as small amounts of lithium. Since they have not been observed so far, much about their structure and life cycle is only described theoretically. It is assumed that they were ten or a hundred times more massive than our sun and ended their lives relatively quickly after a few million years in massive supernovae. Only then were heavier elements such as carbon, oxygen, magnesium, and some iron created, forming the basis for the next stellar population. So far, only remnants of these explosions have been discovered.
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As the group around astronomer Eli Visbal now explains, their simulations have shown that in the observable universe, there should be approximately one galaxy of Population III stars as close to us as LAP1-B. Further away from us—and thus closer to the Big Bang—there should be more, but they would likely be smaller and therefore currently undetectable. However, a galaxy of this kind was already discovered with GLIMPSE-16043, and it was already stated: “If you had to build a galaxy of Population III stars in a factory, you couldn't build a better example.” The second similarly promising candidate is now presented in the Astrophysical Journal Letters.
(mho)
