A smashing discovery Article by Tracey Bryant, adapted from IceCube collaboration Photos courtesy of Frank Schroeder and the IceCube Collaboration March 10, 2021 IceCube detector helps prove 60-year-old theory An electron antineutrino races to Earth from outer space at nearly the speed of light, carrying 6.3 petaelectronvolts (PeV) of energy. Deep in the ice sheet at the South Pole, this high-energy particle smashes into an electron and produces another particle, which quickly decays into a shower of secondary particles. The explosion of light from the collision does not go unnoticed. It is captured by a massive telescope buried in the Antarctic glacier, the IceCube Neutrino Observatory.