JWST and ALMA Find Oxygen in Record-Breaking Early Galaxy JADES-GS-z14-0

Discovered by the James Webb Space Telescope and confirmed by ALMA, the galaxy JADES-GS-z14-0 contained oxygen less than 300 million years after the Big Bang. This finding reveals that generations of massive stars had already been born, lived and died in the infancy of the universe.

Pushing the Boundaries of Cosmic Dawn

Astronomers exploring the earliest chapters of the universe have hit a major milestone. Using the NASA/ESA/CSA James Webb Space Telescope, an international team observed the record-breaking galaxy JADES-GS-z14-0 during the JWST Advanced Deep Extragalactic Survey (JADES) program. According to findings highlighted by ESA and NASA, the galaxy was observed approximately 290 million years after the Big Bang.

This places the galaxy at a staggering redshift of roughly 14. Specifically, NIRSpec data determined the redshift to be 14.32 (+0.08/-0.20). Light from this distant source has been stretched by the expansion of the universe, offering a snapshot of Cosmic Dawn—the period in the first few hundred million years after the big bang where the first galaxies were born, providing insight into the ways in which the gas, stars, and black holes were changing.

Stefano Carniani from Scuola Normale Superiore in Pisa, Italy, and Kevin Hainline from the University of Arizona noted that Webb was specifically engineered to find and understand the earliest galaxies. During its initial observation cycles, the JADES program mapped hundreds of candidate galaxies from the universe’s first 650 million years. However, JADES-GS-z14-0 stood out as an outlier.

Unraveling the Mystery of an Unusually Bright Primordial Galaxy

Finding such a distant galaxy was unexpected, but its luminosity created a puzzle for researchers. Early analysis of the data showed that the source was surprisingly bright for such a distant galaxy. It sat closely adjacent to another galaxy, initially complicating the optical signatures in NIRCam imagery.

To cut through the ambiguity, researchers dedicated nearly ten hours of observation time in January 2024 using Webb’s Near-Infrared Spectrograph (NIRSpec). The resulting spectrum provided unambiguous proof of its extreme distance, shattering the previous most-distant galaxy record held by JADES-GS-z13-0 at a redshift of 13.2. As space data continues to pour in, observations from the Atacama Large Millimeter/submillimeter Array (ALMA) have further confirmed chemical signatures within these early systems.

The Presence of Oxygen Alters Early Universe Models

The significance of JADES-GS-z14-0 goes beyond a simple distance record. The detection of oxygen inside a galaxy existing less than 300 million years after the Big Bang forces astrophysicists to rethink stellar evolution timelines.

Photo: esawebb.org

Finding oxygen this early in cosmic history implies that multiple generations of massive stars had already completed their entire life cycles—forming, evolving, and dying—in a short temporal window.

These observations remain part of active science in progress, with much of the data currently not yet through the peer-review process. Yet, the high-resolution imaging captured across multiple filters—ranging from 0.9 to 4.44 microns using NIRCam and MIRI instruments—continues to provide concrete structural details about how rapidly the early universe managed to enrich itself with heavy elements.