In October 2022, the cosmos put on a fireworks show that every detector on Earth noticed. The explosion, named GRB 221009A, was so bright that it was called the brightest ever observed. It's a gamma-ray burst — a short but incredibly powerful flash that releases as much energy in seconds as the Sun will produce in its entire lifetime.
To catch such events, scientists build enormous facilities. One of them is LHAASO in China, which has thousands of detectors spread over an area the size of a small city. But scientists want to know: how often will these machines see such explosions? In the new study, they took data on gamma-ray bursts collected over years of observations and estimated how many such events three different observatories could catch.
The result: LHAASO will catch about one such burst every 20–25 years, while the new SWGO project in South America will catch one every 2.5–5 years. The difference is huge because SWGO will have a wider field of view and higher sensitivity. This means that in a few years, we'll be able to study gamma-ray bursts much more often and in greater detail.
The gamma-ray burst GRB 221009A was so bright that it would have been visible to the naked eye if it had occurred in our galaxy, and it actually happened billions of light-years away.