James Webb Telescope Discovery Challenges Current Models of Cosmology

Photo: NASA, ESA, CSA, I. Labbe (Swinburne University of Technology) The first images captured revealed six massive galaxies that formed very soon after the Big Bang.

The first images captured by the James Webb Telescope have revealed six massive galaxies that formed very soon after the Big Bang. However, the mass of these galaxies is much greater than what astronomers expected to find at this time in the history of the Universe. This discovery is so amazing that it could challenge current models of cosmology, or even our understanding of how galaxies formed in the early Universe.

One of the features of the James Webb Telescope (TJW) is that it can see much more distant, older, and lower-luminosity celestial bodies than the Hubble Space Telescope. It thus makes it possible to observe the genesis of the Universe.

It was by analyzing the first color images captured by the TJW that a team of researchers from Australian, American, Danish and was able to track down six particularly massive galaxies that formed about 600 million years after the Big Bang, and which are described in an article published in the journal Nature.

In December 2022, it was announced that even older galaxies, dating from 350 to 400 million years after the Big Bang, had been unearthed thanks to the James Webb Telescope, notes Nathalie Nguyen-Quoc Ouellette, deputy director of the Trottier Institute for Research on Exoplanets (iREx) and the Mont-Mégantic Observatory (OMM). “But what's remarkable about this new discovery is the size, maturity and mass of the galaxies. These are highly developed galaxies, almost as massive as our galaxy, the Milky Way,” she points out.

These galaxies would have masses 100 times greater than astronomers thought they should have so early in the history of the Universe. This discovery upsets their conception of the formation of galaxies in the primordial Universe. “According to what these researchers describe, these galaxies grew faster than previously thought. It's surprising that the galaxies studied in the article were able to mature so quickly, in just a few hundred million years, to resemble our Milky Way so early in the history of the Universe. These observations run counter to current cosmological models and the laws of physics that were believed to exist at the beginning of the Universe,” says Nguyen-Quoc Ouellette.

Researchers who made this discovery now apply to confirm the age, distance, nature and real mass of these galaxies by further analysis of the spectra emitted by these galaxies.