  The most energetic astrophysical sources in the Milky Way, cosmic
accelerators capable of producing high-energy cosmic rays, have resisted
discovery for over a century. Up to now, astrophysicists sought these sources
mainly by scouring the Galaxy for the gamma rays they are expected to emit. In
2023, the IceCube Neutrino Observatory discovered high-energy neutrinos from
the Milky Way, inaugurating a telltale stream of evidence of cosmic-ray
production and interaction in the Galaxy.
