Live Science reports:

The James Webb Space Telescope (JWST) has found a galaxy in the early universe that’s so massive, it shouldn’t exist, posing a “significant challenge” to the standard model of cosmology, according to the study authors.

The galaxy, called ZF-UDS-7329, contains more stars than the Milky Way, despite having formed only 800 million years into the universe’s 13.8 billion-year life span. This means they were somehow born without dark matter seeding their formation, contrary to what the standard model of galaxy formation suggests.

How this could have happened is unclear, but much like previous JWST discoveries of other inexplicably massive galaxies in the early universe, it threatens to upend our understanding of how the first matter in the universe formed, or possibly even the standard model of cosmology itself. The researchers published their findings Feb. 14 in the journal Nature.

“Having these extremely massive galaxies so early in the universe is posing significant challenges to our standard model of cosmology,” study co-author Claudia Lagos, an associate professor of astronomy at the International Centre for Radio Astronomy Research, said in a statement. This is because massive dark matter structures, which are thought to be necessary components for holding early galaxies together, did not yet have time to form this early in the universe, Lagos added. [Continue reading…]