When Japanese scientist Toshihiro Fujii discovered a very high energy cosmic-ray event in May 2021, he christened it ‘Amaterasu’. It turned out to be the second-highest-energy cosmic ray to be discovered – so it was apt that he had named it after the sun goddess in Japanese mythology.
According to a paper published in the journal Science in November, Dr. Fujii, an astronomer at Japan’s Osaka Metropolitan University, discovered the cosmic ray when analysing data collected between May 2008 and November 2021 by the Telescope Array Project in the U.S.
Cosmic rays are streams of energetic particles and clusters of particles coming from outer space and the sun. They include protons and alpha particles (nuclei of helium atoms). Only low-intensity cosmic rays reach the earth’s surface. Their energy is mostly lost in the atmosphere itself, as they smash into atoms of the atmospheric gases and produce a shower of other particles. Otherwise life wouldn’t have been possible on the earth.
