A recently identified, non-rotating galaxy from the early universe shows mature dynamics much faster than simulations currently predict, suggesting rapid dynamical settling can occur.

If such spinless early galaxies are more common than expected, cosmological models may need to rethink merger timing and geometry or the feedback processes that suppress star formation.

XMM-VID1-2075, a distant early galaxy observed by JWST, shows no rotation and has ceased star formation, challenging expectations for galaxy growth timelines.

The team intends to search for additional spinless galaxies in the early universe to test theories by comparing observations with simulations.

Overall, the discovery could rewrite parts of the galaxy maturation timeline, influencing our understanding of mass assembly, merger rates, and quenching in the early universe.

Researchers plan to expand the sample with ongoing JWST surveys, performing spectroscopic follow-ups to refine ages, metallicities, and merger histories, and using deeper imaging to verify merger debris.

A proposed scenario suggests a single head-on merger between oppositely rotating galaxies could erase angular momentum within a few hundred million years, producing a slow-rotating, compact system.

Three galaxies from the MAGAZ3NE survey were analyzed with JWST: one rotates, one has an irregular structure, and XMM-VID1-2075 shows strong random motions with no coherent spin.

These JWST results demonstrate a spectrum of early dynamical states and showcase JWST’s ability to resolve internal motions in galaxies more than 11 billion years ago.

The galaxy is extraordinarily massive for its era, having formed many stars but no longer forming new ones, making it an especially compelling target.

The study, led by Ben Forrest of UC Davis and published May 4 in Nature Astronomy, involved an international team with funding from NASA, STScI, and NSF.

Evidence for a recent major merger—seen as off-center light consistent with merger debris—supports the rapid-formation scenario over a multi-merger path to slow rotation.