THEY may be the most powerful explosions in the Universe, but gamma-ray bursts are officially a thing of the past. The only blasts we see happened more than about 3 billion years ago, so there’s no danger of a catastrophic burst wiping out life on Earth.
About once a day, the sky lights up with a spectacular flash of gamma rays. Most are classed as “long” gamma-ray bursts, lasting more than 2 seconds, and astronomers believe they happen when massive stars in distant galaxies dramatically explode at the end of their lives.
Now Shuang Nan Zhang, Jin-Rong Lin and Ti-Pei…
