This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility: A cosmic explosion that announced itself with a modest flash of gamma rays went on to produce one of the brightest afterglows astronomers have recorded in the past 20 years. An international team of astronomers now finds evidence that the surprising mismatch comes down to perspective: Earth was outside the most intensely beamed light from the explosion.
The event, called GRB 260310A, was detected by NASA's Fermi Gamma-ray Space Telescope on March 10, 2026. Its initial gamma-ray flash lasted about 53 seconds and caught the astronomers' attention for apparently releasing little energy. But the glow that followed told them a different story.
In visible light, the afterglow brightened gradually over several hours, becoming brighter than the galaxy that hosted it, before fading away. Then, weeks after the initial flash, its X-ray glow brightened again and remained visible for months. The team, led by the group BHianca at the University of Rome Tor Vergata, enlisted a fleet of telescopes to track the afterglow from X-rays to radio waves.
The campaign brought together NASA's Chandra X-ray Observatory, ESA's XMM-Newton, the Einstein Probe mission, the Large Binocular Telescope and the Karl G. Observations at Calar Alto Observatory revealed the telltale signature of a supernova, confirming that the burst marked the death of a massive star. The study was published in The Astrophysical Journal Letters.
"We see hundreds of GRBs every year, but the oddballs are the most informative ones," says co-author Roberto Ricci, who led the radio observations. "We could explain individual features of this burst, but fitting them all into the same picture proved much harder." Gamma-ray bursts are brief flashes of gamma rays, the most energetic form of light. Many occur when a massive star collapses, launching jets of matter that race outward at nearly the speed of light.
As a jet plows into surrounding gas, it produces an afterglow that telescopes can follow in X-rays, visible light and radio waves. Astronomers most easily detect these explosions when a jet points directly toward Earth. "Much like a flashlight, the jet appears brightest when seen head-on.
Extract — continue reading at the source.
