Astronomers have detected an enormous gamma-ray bubble that could be a source of the Milky Way’s most powerful cosmic rays — high-energy particles that rain down on Earth from space.

The turbocharged galactic accelerator — dubbed a ‘super PeVatron’ — is capable of blasting out cosmic rays at energies of at least 10 petaelectronvolts (PeV; 1016 electronvolts), pushing the upper limits of the energies such particles are thought to reach in the Milky Way.