Last July, a space telescope heard the death cry of a star billions of light-years away. It was the longest outcry of its type ever detected – an astonishing seven hours. Yet its details are still fuzzy. All we know for sure is that it was a violent ending for a star.

The outcry was a gamma-ray burst. Astronomers have discovered thousands of them. They’re usually produced by a supernova – the titanic explosion of a massive star. Energy from the nuclear inferno deep inside the star blasts outward through its poles. That forms narrow jets of gamma rays – the most powerful form of energy. The gamma rays usually last a few seconds or minutes. In that time, though, the burst can emit more energy than the Sun will produce over billions of years.

Follow-up observations showed that the July outburst took place in a galaxy that’s giving birth to many stars – perhaps as the result of a merger with another galaxy. Many of the new stars are hot and massive, so they explode quickly. That makes the galaxy a good breeding ground for gamma-ray bursts.

But the origin of this event isn’t clear. It could have been the result of a supernova. Other possible scenarios include the merger of a black hole with the dead or stripped core of a Sun-like star, or a close encounter between a star and a mid-sized black hole. Such an encounter would have ripped the star apart, forming a trail of incandescent gas – triggering a long outcry from a dying star.

Script by Damond Benningfield