Q&A WITH A GAMMA RAY SPECIALIST

In 2025, astronomers detected a blast from space that lasted seven hours. Now they're uncovering the strange processes behind the exceptional outburst

- Anita Chandran

What is a gamma-ray burst?

Gamma-ray bursts (GRBs) are intense sources of high-energy radiation that we detect on Earth in the form of gamma rays. They were first detected in the 1960s by US military satellites looking for nuclear detonations on Earth, which saw bright bursts of gamma rays coming from the sky. They didn't know what they were, but that was how the term was coined. It wasn't until much later that we started to understand the physical processes that might cause them.

How do we detect GRBs?

Primarily we use widefield, high-energy monitoring, typically with space telescopes that see a very large part of the sky at a time. They scan everything at once and pick up anything that looks like a bright pulse compared to the background noise.