At the time New Eyes on the Universe was published, the only confirmed sources extraterrestrial neutrinos were the Sun and SN1987A. The view of the sky afforded by neutrino telescopes was rather dull.
That view of the neutrino sky is beginning to change. The IceCube SouthPole Neutrino Observatory – a “telescope” consisting of particle detectors buried in one cubic kilometre of Antarctic ice – has detected 28 neutrinos with an energy in excess of 30 TeV (a teraelectronvolt is 1012 eV). Two of these neutrinos, dubbed Bert and Ernie, had energies in excess of 1 PeV (that’s 1015 eV) – far in excess of energies available at the Large Hadron Collider.
It’s possible that Bert and Ernie were produced by high-energy cosmic rays smashing into Earth’s atmosphere, but an extraterrestrial origin for these neutrinos does seem more likely than not. And If IceCube has indeed detected high-energy neutrinos from the depths of space the question becomes: what was their source? That’s where things get interesting. If they came from some violent astrophysical source then astronomers have a telescope that lets us study them. Or perhaps they came from the decay of dark matter particles – a suggestion made in a recent preprint by Arman Esmaili and Pasquale Serpico (Are IceCube neutrinos unveiling PeV-scale decaying dark matter?). Whatever the source of Bert and Ernie turns out to be, it seems certain that IceCube truly is giving us some new eyes through which to view the universe.