6 APRIL 2021 A cosmic gamma ray detected zipping across the Milky Way has broken the record for the most energetic we've found yet, clocking in at a whopping 957 trillion electronvolts (teraelectronvolts, or TeV). This not only more than doubles the previous record, it brings us close to the range of petaelectronvolts (that's a quadrillion electronvolts) - finally confirming the existence of cosmic superaccelerators that can boost photons to these energies in the Milky Way. Such a superaccelerator is called a PeVatron, and finding them could help us figure out what is producing the high-e...