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.

The Unusual Burst

Detected by NASA's Fermi Gamma-ray Space Telescope on July 2, 2025.
Named GRB 250702B.
Had repeating explosive bursts over days.
Most gamma-ray bursts last only a few minutes, making this one very special.

Possible Cause

Scientists think this burst could be from a rare type of black hole, 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.

Studying the Burst

To study this burst, astronomers used powerful telescopes:

Very Large Telescope (VLT) in Chile.
Víctor M. Blanco Telescope.
Twin Gemini telescopes.

The burst came from a galaxy billions of light-years away from the Milky Way. The afterglow was studied using these telescopes.

The Burst's Characteristics

The 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 more massive than others.

Possible Explanations

Scientists have three ideas about what caused this burst:

A black hole colliding with a star.
A smaller body, like a planet, getting torn apart by a black hole or neutron star.
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.

Conclusion

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.