Neutrino Tracks
The sun produces huge volumes of nearly massless particles called neutrinos. Neutrinos ('little neutron in Italian, coined by Enrice Fermi) reveal themselves when one strikes an atom and generates a flare of light, but the event is rare. This image shows what this event looks like inside a liquid-filled neutrino detector buried deep underground. The direction and intensity of the flare indicates the source and energy of the neutrino. A neutrino is any of three electrically neutral subatomic particles with extremely low mass. These include the electron-neutrino, the muon-neutrino, and the tau-neutrino. The study of neutrinos that come to the earth as cosmic rays suggests that neutrinos can transform into each other in a process called neutrino oscillation. For this phenomenon to be theoretically possible, the three neutrinos must have distinct masses; for this reason, many scientists believe that they have mass
