The Unique Galaxy Reveals Surprisingly Untouched Stars.

In the vast expanse of the universe, galaxies that exhibit peculiar contours are surprisingly filled with ancient stars. This offers astronomers an initial peek into a unique type of stellar body that emerged soon after the universe’s inception.

Although the James Webb Space Telescope (JWST) has allowed scientists to revisit regions of the early universe, pinpointing the first stars remains elusive. These primordial stars, termed Population III stars, are primarily colossal hydrogen spheres believed to have formed in the universe’s infancy. As the very first stars, they left behind an environment largely devoid of heavier elements following their demise.

While there have been theories hinting at the existence of such stars, definitively proving their existence in the early universe has been challenging, as galaxies appeared to have become tainted with heavier elements merely a few hundred million years post-Big Bang.

Recently, Morihara Highlands from the California Institute of Technology and his team found a galaxy almost entirely composed of hydrogen, indicating the presence of Population III stars. However, this galaxy emerged later than expected, approximately a billion years after the universe began.

Dubbed Amore6, it was initially identified within the Abell 2744 galaxy cluster. Upon measuring the light from Amore6 using the JWST, Morishita and his colleagues noted the complete absence of common oxygen ions. This suggests that the galaxy harbors less than 0.2% of the oxygen present in our sun, indicating a lack of contamination by heavier elements.

As the universe evolves, the likelihood of encountering such pristine galaxies diminishes. In images captured by the JWST, Amore6 appears somewhat isolated, which Morishita posits could be a factor in its untouched state. “This seclusion might mean that this galaxy has not yet encountered sufficient gas to trigger star formation, implying that it could evolve slowly,” he mentions.

“If these findings are validated, it would be truly astonishing, as we did not anticipate discovering such an untarnished galactic environment later in the universe’s development,” says Fabio Pacucci of the Harvard Smithsonian Astrophysics Center in Massachusetts.

This discovery has implications for observing “direct collapse” black holes. Unlike the conventional pathway of collapsed stars, these black holes form from massive clouds of untainted gas. While astronomers had predicted their existence, they have never actually formed as it was believed that primitive gas was only available for a limited period, up to 100 million years after the Big Bang. However, if this untainted gas can persist for an extended duration, the potential for observing such phenomena increases, Pacucci argues.

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