115: Zevatron in the Void

Astronomers routinely detect cosmic rays, the high-energy particles from space that collide with molecules in the upper atmosphere, creating a shower of secondary particles that rain down on the earth below. But every so often — like, less than once a decade — they spot a cosmic ray smashing into the planet with just stupid amounts of energy. The sort of energy you associate with hitting a golf ball or maybe dropping a brick on your foot, but definitely NOT a single subatomic particle. Not only do astronomers have no idea what could produce these Ultra High Energy Cosmic Rays, one was spotted recently that seems to have originated in one of the emptiest regions of the universe. Emily explains the Strange Mystery of the Cosmic Zevatron.