S. Bradley Cenko

A gamma-ray burst is a short but incredibly powerful explosion in a distant galaxy. In a few seconds, it releases as much energy as the Sun will emit over billions of years. The Neil Gehrels Swift satellite catches such flashes with a special telescope called BAT, which detects gamma rays.

The center of a galaxy is a bustling metropolis where a giant black hole often snatches inattentive stars. But telescopes caught a flare in a quiet suburb, tens of thousands of light-years from the core. This gave away a wandering black hole — an invisible predator, flung out of the center after an ancient galaxy collision.

For years, silence reigned in the heart of galaxy 1ES 1927+654: the accreting gas merely whispered in X-rays, leaking slow winds. But in 2022–2025, the picture changed dramatically. Spectra taken by XMM-Newton and Swift lit up with emission lines — a narrow peak at 0.56 keV, likely from OVII oxygen, a broader feature near 1 keV, and a powerful iron band in the 6–7 keV region.