The James Webb Space Telescope has confirmed the oldest supernova ever observed, linked to GRB 250314A just 730 million years after the Big Bang, offering rare insights into the universe’s earliest stars and galaxies.
Webb spots record-breaking supernova, illuminating the universe’s dawn
Photo Credit: Space
Astronomers with the James Webb Space Telescope (JWST) reported the discovery of the oldest supernova ever seen — a blast linked to a time when the cosmos was just around 730 million years old. As a result of its association with gamma-ray burst GRB 250314A, this finding exemplifies the power of the Webb to trace the most remote stellar explosions in the universe and to provide insight into the formation of the first galaxies and stars.
According to the paper, this violent event, labelled GRB 250314A, was initially identified by the French–Chinese SVOM satellite on March 14, 2025, as a bright gamma-ray flash – the extreme-energy signature of the most powerful events in the universe. Subsequent observations by ground-based telescopes and JWST enabled scientists to determine its redshift of about 7.3, thus locating the explosion only 730 million years after the Big Bang.
After that, the Near-Infrared Camera (NIRCam) of Webb captured the dim, reddened light of the supernova and the galaxy that hosted it, thereby verifying the earliest supernova as the one observed so far, and Webb's own record at 1.8 billion years after the Big Bang was broken.
Such discoveries offer a unique chance to study the host environments that give rise to the first star generations in the universe. Understanding star formation, metal production, and galaxy growth well below these extremely early times is possible because JWST resolves the host galaxy. This outcome validates Webb's potent ability to examine individual stellar explosions from the first billion years of the universe, providing fresh perspectives on cosmic origins.
For details of the latest launches and news from Samsung, Xiaomi, Realme, OnePlus, Oppo and other companies at the Mobile World Congress in Barcelona, visit our MWC 2025 hub.