The signal was mistakenly attributed to a distant galaxy
© NASA/ESA
A signal that scientists first believed was the discovery of a gamma-ray burst from the oldest known galaxy in the universe was in fact a reflection of sunlight from a spent rocket stage. The disappointing conclusion comes from a team of Polish scientists following a discussion involving several teams about the origin of the serendipitous sighting made by one of the twin Keck telescopes in Hawaii in 2017. Whereas previous contributions to the debate focused on the probability of seeing a satellite compared to an extremely rare gamma-ray burst, the Polish team managed to track down the exact object that caused the flash: a spent Briz-M upper stage from a Russian Proton rocket.