Among the questions, scientists hope to answer: Where do the highest energy neutrinos originate? How do neutrinos get their mass? Below, see a few reasons neutrinos have been making the news this summer.Three flavors of neutrinos—the electron, muon, and tau neutrinos—are currently known to science. At the Borexino neutrino observatory in Italy’s Gran Sasso National Laboratory , scientists recently reported that they had detected neutrinos made in the CNO (carbon-nitrogen-oxygen) cycle—a nuclear fusion process that occurs inside the sun. The direct observation of these neutrinos is the first evidence that the CNO reaction actually happens in stars.