A surprising chemical signature
Paris — Astronomers have detected oxygen in the most distant galaxy ever observed—a discovery that has left scientists astonished and offers new insight into how quickly stars formed in the early universe.
The galaxy, named JADES-GS-z14-0, was first identified last year by NASA’s James Webb Space Telescope. Its light has traveled an astonishing 13.4 billion years to reach Earth, providing a glimpse into a time when the universe was just 300 million years old—barely two percent of its current age.
The unexpected presence of oxygen suggests that stars in this ancient galaxy matured far more rapidly than previously thought. Since its launch in 2022, the Webb telescope has upended earlier assumptions, revealing that young galaxies were brighter, more evolved, and more abundant than scientists had predicted.
Using the ALMA radio telescope in Chile’s Atacama Desert, two international teams—one led by Dutch astronomers, the other by Italians—confirmed traces of oxygen in JADES-GS-z14-0, a finding announced by the European Southern Observatory.
Traditionally, galaxies from this era, known as the cosmic dawn, were expected to host young stars composed mainly of light elements like hydrogen and helium. Heavier elements, such as oxygen, were thought to emerge only later as stars aged and died. Yet, JADES-GS-z14-0 boasts 10 times more heavy elements than anticipated, a revelation that has left experts scrambling to explain.
“It is like finding an adolescent where you would only expect babies,” said Sander Schouws of Leiden Observatory, lead author of a Dutch-led study set for publication in The Astrophysical Journal. “The results show the galaxy has formed very rapidly and is also maturing rapidly, adding to a growing body of evidence that the formation of galaxies happens much faster than was expected,” he added in a statement.
Rethinking galactic evolution
The Italian-led team, spearheaded by astrophysicist Stefano Carniani, echoed the amazement. “I was astonished by the unexpected results,” said Carniani, whose findings will appear in Astronomy & Astrophysics. “The evidence that a galaxy is already mature in the infant universe raises questions about when and how galaxies formed.”
Since its launch, the Webb telescope has consistently defied expectations, prompting some to wonder if our understanding of cosmic evolution is missing a critical piece. The oxygen detection in JADES-GS-z14-0 intensifies that debate, suggesting stars in the early universe forged heavy elements at an accelerated pace—potentially reshaping models of galaxy formation.
A window into the cosmic dawn
Located at the edge of observable space, JADES-GS-z14-0 serves as a time capsule, its light capturing a universe in its toddler years. The presence of oxygen so early hints at a frenetic burst of star birth and death, defying the gradual timeline astronomers once envisioned. As research continues, this distant galaxy may hold the key to unlocking the secrets of how the cosmos matured from a primordial soup into the vast expanse we know today.
