P. O'Brien

On the night of August 18, 2025, the SVOM space telescope detected a short gamma-ray burst — a powerful flash of energy lasting less than two seconds. Such bursts are usually linked to mergers of neutron stars, the ultra-dense remnants of dead stars.

Massive stars end their lives in a colossal explosion, which Fritz Zwicky called a supernova. The core crushes down into a black hole or a neutron star.

At the center of the Milky Way, where the supermassive black hole Sagittarius A* churns gas clouds like a millstone, astronomers have caught an irregular pulse. Gamma-ray emission, the most energetic light in the universe, arrives not as a smooth wave but with a break, as if the Galaxy's heart beats with arrhythmia.