In 1992 the fastest object known to mankind hit the Earth's atmosphere at a speed within a billion-trillionth of one percent of the speed of light, carrying an energy far above that of the most powerful particle accelerator ever built. That object was a cosmic ray.Over 100 cosmic ray particles pass through our bodies every second. Some of these have enormous energies, far above those accessible using man-made particle accelerators. Many of them have traveled millions of light years across the Universe, and they bring with them clues about exotic astronomical systems like neutron stars,...