Observations of high-energy astrophysical neutrinos have shown that they mostly originate from extragalactic sources such as active galaxies. However, gamma ray observations show bright emission from within the Milky Way galaxy, and astrophysical gamma rays and neutrinos are expected to be produced by the same physical processes. The IceCube Collaboration searched for neutrino emission from within the Milky Way (see the Perspective by Fusco) and found evidence of extra neutrinos emitted along the plane of the Galaxy, which is consistent with the distribution of gamma-ray emission. These results imply that high-energy neutrinos can be generated by nearby sources within the Milky Way.

-Editor’s summary from the Science article