Cosmic rays striking Earth come from outside Milky Way: study
(World News Science)

Ultra-high-energy cosmic rays that occasionally hit the Earth may be coming from a distant source outside the Milky Way galaxy, a study suggests. Fifty years ago, scientists discovered that the Earth is occasionally hit by cosmic rays of enormous energies. Since then, they have argued about the source of those ultra-high-energy cosmic rays - whether they came from our galaxy or outside the Milky Way. The answer lies in a galaxy or galaxies far,...