Scientists trace high-energy cosmic neutrino to its birthplace

A pair of results bring neutrinos into the new era of multi-messenger astronomy. On September 22, 2017, a tiny but energetic particle pierced Earth's atmosphere and smashed into the planet near the Amundsen-Scott South Pole Station in Antarctica. The collision set loose a second particle, which lit a blue streak through the clear ice. Luckily for science, the first particle was a neutrino, and the strike occurred within the cubic kilometer that makes up the IceCube neutrino experiment. Its detec...