ALMA Discovers Oxygen in Most Distant Known Galaxy  

Two different scientific teams have detected oxygen in JADES-GS-z14-0. The breakthrough, reported in two separate studies, was made possible thanks to the Atacama Large Millimeter/submillimeter Array (ALMA). This record-breaking detection makes astronomers rethink how quickly galaxies formed in the early universe. 

Discovered in 2024, JADES-GS-z14-0 is the most distant confirmed galaxy ever found. Its light took 13.4 billion years to reach us, meaning we see it as when the universe was less than 300 million (about 2% of its present age). The new oxygen detection with ALMA suggests the galaxy is more chemically mature than expected. 

"It is like finding an adolescent where you would only expect babies," says Sander Schouws, a PhD candidate at Leiden Observatory, Netherlands, and first author of the Dutch-led study. "The results show the galaxy has formed and matured very rapidly, adding to a growing body of evidence that the formation of galaxies happens much faster than expected."  

Galaxies usually start their lives with plenty of young stars, which are made mostly of light elements like hydrogen and helium. As stars evolve, they create heavier elements like oxygen, which get dispersed through their host galaxy after they die. Researchers thought that, at 300 million years old, the universe was still too young to have galaxies ripe with heavy elements. However, the two ALMA studies indicate that JADES-GS-z14-0 has about 10 times more heavy elements than expected. 

"I was astonished by the unexpected results because they opened a new view on the first phases of galaxy evolution," says Stefano Carniani of the Scuola Normale Superiore of Pisa, Italy, and lead author on the second paper. "The evidence that a galaxy is already mature in the infant Universe raises questions about when and how galaxies formed." 

The oxygen detection has also allowed astronomers to make their distance measurements to JADES-GS-z14-0 much more accurate. "The ALMA detection offers an extraordinarily precise measurement of the galaxy's distance down to an uncertainty of just 0.005%. This level of precision — analogous to being accurate within 5 cm over 1 km — helps refine our understanding of distant galaxy properties", adds Eleonora Parlanti, a PhD student at the Scuola Normale Superiore of Pisa. 

"While the galaxy was originally discovered with the James Webb Space Telescope (JWST), it took ALMA to confirm and precisely determine its enormous distance," says Associate Professor Rychard Bouwens, a team member at Leiden Observatory.". This shows the amazing synergy between ALMA and JWST to reveal the formation and evolution of the first galaxies." 

Gergö Popping, an European Southern Observatory (ESO) astronomer at the European ALMA Regional Centre who did not participate in the studies, says: "I was really surprised by this clear detection of oxygen in JADES-GS-z14-0. It suggests galaxies can form more rapidly after the Big Bang than previously thought. This result showcases the important role ALMA plays in unraveling the conditions under which the first galaxies in our universe formed." 

Additional information 

The results of the studies are published in the following papers: 

• Carniani et al. "The eventful life of a luminous galaxy at z=14: metal enrichment, feedback, and low gas fraction?" 

• Schouws et al. “Detection of [OIII]88μm in JADES-GS-z14-0 at z=14.1793” 

The European Southern Observatory (ESO), an ALMA partner on behalf of Europe, published the original press release. 

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