First evidence of super cosmic ray accelerator found in Milky Way

A team of Chinese researchers has found a giant bubble of ultra-high-energy gamma rays in the Cygnus region of the Milky Way, which reveals the origin of the most energetic cosmic rays ever detected.
Peta-Electronvolt cosmic rays
Cosmic rays are mysterious particles from outer space that bombard the Earth with incredible energies. Some have more than 10 Peta-Electronvolt (PeV, 1PeV=1015eV) energy, millions of times higher than the largest human-made particle accelerator, the Large Hadron Collider. But where do these cosmic rays come from, and how are they accelerated to such extreme energies?