On December 6, 2016, a high-energy particle called an electron antineutrino hurtled to Earth from outer space at close to the speed of light carrying 6.3 petaelectronvolts (PeV) of energy. Deep inside the ice sheet at the South Pole, it smashed into an electron and produced a particle called W– boson, which quickly decayed into a cascade of high-energy particles (a particle shower). The interaction was captured by the IceCube Neutrino Observatory,...
