About This Lesson
On Sept. 22, 2017, the National Science Foundation's IceCube Neutrino Observatory alerted the international astronomy community that a high-energy neutrino had passed through the Earth. That notification set in motion follow-on observations from nearly two dozen observatories on Earth and in space, ultimately confirming the source of the neutrino, a first for science. This brief video explains the discovery and how it has helped resolve a 100-year mystery about the sources of high-energy cosmic rays.
