Using JWST and gravitational lensing, astronomers have identified compelling candidates for Population III — the universe’s first stars — in galaxy LAP1-B, more than 13 billion light-years away. The magnified spectrum shows helium but almost no heavier elements, matching expectations for metal-free stars. The result is promising but not yet conclusive: pristine gas clouds could mimic the signal. Deeper spectroscopy, particularly searching for oxygen, will be needed to confirm the discovery.
JWST May Have Spotted the Universe’s First Stars: Strong Population III Candidates in LAP1-B
Using JWST and gravitational lensing, astronomers have identified compelling candidates for Population III — the universe’s first stars — in galaxy LAP1-B, more than 13 billion light-years away. The magnified spectrum shows helium but almost no heavier elements, matching expectations for metal-free stars. The result is promising but not yet conclusive: pristine gas clouds could mimic the signal. Deeper spectroscopy, particularly searching for oxygen, will be needed to confirm the discovery.
05:40 AM, 11/20/2025Science
A team using the James Webb Space Telescope (JWST) reports the strongest candidates yet for the universe’s first stars — so-called Population III stars — in a galaxy labeled LAP1-B, located more than 13 billion light-years away.
These hypothetical first-generation stars would have formed from primordial hydrogen and helium shortly after the Big Bang. They are predicted to have burned extremely hot and lived very briefly before exploding as powerful supernovas that forged the heavier elements later incorporated into subsequent generations of stars, planets and chemistry.
Light from LAP1-B has been magnified by a nearer galaxy cluster acting as a gravitational lens, giving JWST the sensitivity needed to study the galaxy’s faint spectrum. The new observations show clear signatures of helium but reveal almost no heavier elements (“metals” in astronomical terms). That pattern is exactly what astronomers expect from a stellar population dominated by metal-free, first-generation stars.
The team published their analysis in October in Astrophysical Journal Letters. While the helium-rich and metal-poor spectrum is encouraging, the result is not yet definitive. The same spectral pattern could also come from unusually pristine, metal-poor gas clouds rather than from clusters of Population III stars.
“An absence of evidence is not evidence of absence,”says astronomer Jorryt Matthee, who was not involved in the study. He and other independent experts call this the closest approach yet to finding the earliest stars but emphasize that stronger, follow-up evidence is required.
Deeper spectroscopy of LAP1-B — especially a confirmed non-detection of oxygen and other heavy elements — would significantly strengthen the Population III interpretation. Future JWST observations, combined with other telescopes and improved lensing models, will be important to rule out alternate explanations.
Why this matters: Confirming Population III stars would fill a major gap in our knowledge of cosmic history by directly revealing the objects that produced the first heavy elements and set the stage for galaxy and planet formation.