Ancient galaxies, observed through the James Webb (JWST) space telescope, have displayed an unusually high level of brightness. Scientists have now uncovered the reason behind this intriguing phenomenon.
The researchers have determined that these galaxies, which existed in the early Universe, went through periods of intense star formation. This process likely caused them to appear brighter than initially expected. The conclusions were drawn based on computer simulations of the galaxy formation and early stages of star formation.
The JWST began its scientific observations in the summer of 2022, capturing images of galaxies with a high redshift. These galaxies existed during the early stages of the Universe. Surprisingly, they were found to be significantly brighter than what the standard cosmology model predicted. Claude Andre Foshe-Zhiger from the University of Noretvezerns commented, “The discovery of these galaxies was a great surprise, because their brightness was significantly higher than expected.”
A team of scientists, led by GOUCHAO from CALTECH, alongside Foshe-Zhiger, concluded that the high brightness of the galaxies observed by the JWST was a result of the intense star formation process. Foshe-Zhiger added, “If star formation occurs in bursts, this leads to flashes of light. That’s why we see some very bright galaxies.”
In the early Universe, galaxies were much fewer in number compared to present times, and they grew by merging with other galaxies and through the influx of intergalactic gas clouds. Notably, the results of the new modeling align with the standard model of cosmology. Foshe-Zhiger concluded, “Our models show that galaxies could easily form with such brightness at the dawn of the universe.”
The findings of this study were published on October 3 in the Astrophysical Journal Letters.