First direct electron observation in tera electron volt region

Japan Aerospace Exploration Agency (JAXA) and Waseda University started global-leading direct electron observations in the extremely high-energy region of Tera electron volt (TeV, one trillion electron volts) using the CALorimetric Electron Telescope (CALET) installed on the Exposed Facility of the Japanese Experiment Module "Kibo" of the International Space Station (ISS).