Observed over Utah in 1991 by a cosmic ray detector, the Oh-My-God particle was a rare ultra-high-energy cosmic ray that traveled through the universe at very nearly the speed of light. Since then, scientists have detected a number of other cosmic rays with similarly high energies. Such subatomic particles carry millions of times the energy that can be generated in a particle accelerator. Their origin is still unclear, but they could be related to dark matter. What might be generating them? Discuss
Source: The Free Dictionary