Astronomers have discovered a remarkably clumpy rotating galaxy that existed just 900 million years after the Big Bang. Dubbed “Cosmic Grapes,” the galaxy is composed of at least 15 massive star-forming clumps, far more than current theoretical models predict could exist within a single rotating disk.
The discovery was made possible by an extraordinary combination of observations from the Atacama Large Millimeter/submillimeter Array (ALMA) and the James Webb Space Telescope. This single galaxy was perfectly magnified by a foreground galaxy cluster through gravitational lensing, allowing for over 100 hours of telescope time to be dedicated to it.
Contrary to previous Hubble images that showed a smooth disk-like object, ALMA and JWST revealed a rotating galaxy teeming with massive clumps, resembling a cluster of grapes. This finding marks the first time astronomers have linked small-scale internal structures and large-scale rotation in a typical galaxy at cosmic dawn.
The Cosmic Grapes do not represent an extreme or rare system but instead lie on the “main sequence” of galaxies, indicating it is likely representative of a broader population. This discovery raises key questions about how galaxies form and evolve, suggesting that our understanding of feedback processes and structure formation may need significant revision.
Source: https://www.newswise.com/articles/the-universe-s-secret-harvest-alma-sheds-light-on-the-cosmic-grapes