The standard model for how galaxies formed in the early universe predicted that the James Webb Space Telescope (JWST) would see dim signals from small, primitive galaxies. But data are not confirming the popular hypothesis that invisible dark matter helped the earliest stars and galaxies clump together.

Astronomers have used the James Webb Space Telescope to observe three early ultra-massive galaxies, formed shortly after the Big Bang.

The standard model for how galaxies formed in the early universe predicted that the James Webb Space Telescope (JWST) would see dim signals from small, primitive galaxies. But data are not confirming