50-yr-old mystery of high-energy cosmic rays' origin solved
A collaboration of 400 researchers from 18 countries at the Argentina-based Auger Observatory has found "compelling evidence" that the sources of the ultra-high-energy cosmic rays lie outside the Milky Way galaxy. Discovered in 1960s, cosmic rays are known to possess million times more energies than protons in the Large Hadron Collider, the world's largest and most powerful particle accelerator.