Astronomers using the James Webb Space Telescope have identified AT 2026abck, potentially one of the most distant supernovas ever observed. The explosion emitted its light more than 12.5 billion years ago, when the cosmos had existed for only about 1.15 billion years—under 10% of its age today. Researchers estimate that their observations capture the event just four to 10 days after the explosion began.
At peak brightness, the supernova shines roughly 8 billion times brighter than the sun, nearly rivaling the entire Milky Way. Its temperature exceeds 30,000 degrees Fahrenheit. Its host galaxy, ID101411, forms stars more than ten times faster than the Milky Way. The discovery emerged from the NEXUS Treasury program, which repeatedly surveys selected areas of sky for ancient explosions. Webb detected the event on August 7, 2026; it had not appeared in the telescope’s May 28 observation. Unlike many similarly distant discoveries, this detection required no gravitational lensing—the magnification of background light by a massive foreground object.
Cosmic expansion makes the explosion appear to evolve about six times more slowly: a week of change at the supernova unfolds over roughly six weeks from Earth’s perspective. The team provisionally suspects a superluminous supernova, a rare class releasing tens or hundreds of times more energy than conventional supernovas. Follow-up observations will track whether the event heats up or cools, helping researchers determine its nature and investigate the conditions surrounding the explosion.
