Using data from the large scale structure of galaxies, the Cosmic Microwave Background (CMB), Type Ia supernovae, and Big Bang nucleosynthesis, a team of physicists has calculated the maximum possible mass of the lightest neutrino species. The world’s first neutrino observation in a hydrogen bubble chamber. It was found November 13, 1970, on this photograph from the Zero Gradient Synchrotron’s 12-foot bubble chamber. The invisible neutrino strikes...
