The longest gamma-ray burst ever recorded, lasting seven hours, could be the result of an elusive intermediate-mass black hole devouring a star. This cosmic explosion, detected on July 2, 2025, by NASA's Fermi Gamma-ray Space Telescope, stands out among the 15,000 GRBs detected so far. Astronomers turned to the Very Large Telescope (VLT) in Chile to pinpoint the location of the burst, a galaxy billions of light-years away from the Milky Way. Further investigation using powerful ground-based telescopes revealed clues about the burst's origin. The initial gamma-ray signal emerged from a narrow, near-light-speed jet of plasma, indicating a vast amount of dust around the emission point. The host galaxy is also more massive than those of other GRBs. Current theories suggest GRBs occur when massive stars collapse, extreme neutron stars are born, or black holes rip apart stars. However, this burst doesn't fit neatly into any of these scenarios. Researchers propose three potential mechanisms: a black hole colliding with a stripped star, a micro-tidal disruption event, or an intermediate-mass black hole, which is rarely detected. This last scenario, if confirmed, would be groundbreaking, as it would be the first time astronomers observe an intermediate-mass black hole producing a plasma jet after tearing apart a star. The team's research, published in The Astrophysical Journal Letters, highlights the ongoing mysteries of the universe's extreme events, inviting further exploration and discovery.
