Space.com reported, "Much of scientists' previous understanding on galaxy evolution came from data gathered by the Hubble Space Telescope (HST), which is legendary in its own right but still has only so much resolution. While the HST data showed early galaxies had irregular shapes (as was expected during galaxy mergers) higher resolution data from the JWST is peering deeper into the universe to reveal that those early galaxies actually had well-defined structures like our own Milky Way. The new findings were based on an analysis of 3,956 galaxies, which astronomers say is the biggest sample that has been studied thus far with JWST data."
Some thoughts here. Looks like JWST observations and findings continue to challenge the LCDM BB cosmology but the paper puts their best foot forward it seems
. From the paper cited,
https://iopscience.iop.org/article/10.3847/1538-4357/acec76
"All sources were classified by six individual classifiers using a simple classification scheme aimed at producing disk/spheroid/peculiar classifications, whereby we determine how the relative number of these morphologies has evolved since the Universe's first billion years. Additionally, we explore structural and quantitative morphology measurements using Morfometryka, and show that galaxies with M* > 10^9 M⊙ at z > 3 are not dominated by irregular and peculiar structures, either visually or quantitatively, as previously thought. We find a strong dominance of morphologically selected disk galaxies up to z = 6 in this mass range. We also find that the stellar mass and star formation rate densities are dominated by disk galaxies up to z ∼ 6, demonstrating that most stars in the Universe were likely formed in a disk galaxy. We compare our results to theory to show that the fraction of types we find is predicted by cosmological simulations, and that the Hubble Sequence was already in place as early as one billion years after the Big Bang. Additionally, we make our visual classifications public for the community."..
Quantitative measures of galaxy structure and morphology also present stringent constraints for numerical simulations to reproduce. In recent years, full hydrodynamic simulations (Schaye et al. 2015; Nelson et al. 2019; Lovell et al. 2021; Marshall et al. 2022) have enabled resolved morphologies to be predicted in a self-consistent manner, and recent novel simulation approaches allow these to be tested out to the highest redshifts (Roper et al. 2022). There are a number of difficulties when comparing morphologies between simulations and observations, but simple measures of the abundance of, e.g., disk and elliptical galaxies can provide hints as to the underlying mechanisms leading to morphological evolution. However, what we know from early JWST work is that the morphological and structural features of galaxies at z > 1 are much different than what was found with HST (e.g., Ferreira et al. 2020), and therefore a more thorough analysis is needed to address these fundamental problems. Thus, in this paper we explore the morphological properties of 3956 galaxies observed with JWST through visual galaxy classifications and quantitative morphology, from z = 1.5 to 6."
The cosmology calculators for z=6.0, show the age of the universe since BB event at "The age at redshift z was 0.942 Gyr." using Ned Wright with defaults. Plug in H0 = 73 km/s/Mpc and "The age at redshift z was 0.898 Gyr.",
https://lambda.gsfc.nasa.gov/toolbox/calculators.html
It does appear now that JWST is finding objects with large redshifts that pose some real challenges now to the BB model to explain how the universe assembled into what we see today using our telescopes.
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