James Webb Space Telescope spots 'Sparkler Galaxy' that could host universe's 1st stars

An interesting report. I am not sure how to understand it though like the globular clusters, are they Population III stars, e.g., *universe's fist stars*? Some follow up reports I feel will be needed. For example, the 9 billion light years distance from Earth looks like z ~ 1.5 using cosmology calculators. The article does disclose that a lensing object could be 10 to 100x gravitational lens, still to be determined. "The magnification of the Sparkler Galaxy and its surroundings is not as well constrained as we'd like," Iyer said. "So one of the things we want to do is build a better magnification model so that we can figure out whether it's enlarged by a factor of 10 or by a factor of 100."

I did find this earlier report. Star formation at the smallest scales; A JWST study of the clump populations in SMACS0723, [2208.10450] Star formation at the smallest scales; A JWST study of the clump populations in SMACS0723 (arxiv.org), 22-August-2022.

“We present the clump populations detected in 18 lensed galaxies at redshifts 1 to 8 within the lensing cluster field SMACS0723. The recent JWST Early Release Observations of this poorly known region of the sky have revealed numerous point-like sources within and surrounding their host galaxies, undetected in the shallower HST images. We use JWST multiband photometry and the lensing model of this galaxy cluster to estimate the intrinsic sizes and magnitudes of the stellar clumps. We derive optical restframe effective radii from <10 to 100s pc and masses ranging from ∼10^5 to 10^8 M⊙, overlapping with massive star clusters in the local universe. The ages range from 1 to 100s Myr. We compare the crossing time to the age of the clumps and determine that between 30 and 50 % of the detected clumps are consistent with being gravitationally bound. The lack of Gyr old clumps suggest that the dissolution time scales are shorter than 1 Gyr. We see a significant increase in the luminosity (mass) surface density of the clumps with redshift. Clumps in galaxies at the reionisation era have stellar densities higher than massive clusters in the local universe. We zoom-in into single galaxies at redshift <6 and find for two galaxies, the Sparkler and the Firework, that their star clusters/clumps show distinctive color distributions and location within and surrounding their host galaxy that are compatible with recent (100-500 Myr) merger events. Our study, conducted on a small sample of galaxies, shows the potential of JWST observations for understanding the conditions under which star clusters form in rapidly evolving galaxies.”

Using the cosmology calculators, z ~ 20 or larger for Population III stars today, if they could be seen using JWST directly. The recent report of H0 = 75 km/s/Mpc using 56,000 galaxy distances could change much in the BB model too.

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