A Cosmic Burst That Lasted for Days: What Caused It?

Astronomers have made a big discovery. They found a cosmic explosion that lasted for seven hours. This is the longest gamma-ray burst ever seen. It was detected by NASA's Fermi Gamma-ray Space Telescope on July 2, 2025. The burst, named GRB 250702B, is different from others. It had repeating explosive bursts over days. Most gamma-ray bursts last only a few minutes. This makes GRB 250702B very special. Scientists think this burst could be from a rare type of black hole. They call it an intermediate-mass black hole. This black hole might have destroyed a star. The burst was so strong that it stood out among the 15, 000 gamma-ray bursts detected so far. To study this burst, astronomers used powerful telescopes. They found that the burst came from a galaxy far away. This galaxy is billions of light-years from the Milky Way. The burst's afterglow was studied using the Very Large Telescope (VLT) in Chile. They also used the Víctor M. Blanco Telescope and the twin Gemini telescopes. The burst's initial gamma-ray signal came from a narrow, fast-moving jet of plasma. This jet hit surrounding gas and dust. The galaxy where this happened has a lot of dust. The host galaxy of GRB 250702B is also more massive than others. Scientists have three ideas about what caused this burst. The first idea is a black hole colliding with a star. The second idea is a smaller body, like a planet, getting torn apart by a black hole or neutron star. The third idea is an intermediate-mass black hole ripping apart a star. This would be the first time such a black hole has been seen producing a plasma jet. This discovery shows how much we still have to learn about the universe. It reminds us that there are many mysteries out there waiting to be uncovered.