National Geographic: The most intense flashes of lightning can do more than just light up the sky: Lightning sometimes acts as a natural particle accelerator, firing beams of electrons at high speeds toward space, a new study says. To start the accelerator, a powerful lightning strike needs to coincide with a burst of cosmic rays–high-energy particles coming from space. ee recent pictures of lightning created in the ash plume of an Iceland volcano.) When cosmic rays enter our atmosphere, they …