Neutrinos were subatomic particles that could pass through most matter. They could be detected with neutrino detectors, which were vats of cleaning fluid with sensors inside. In the rare instances when a neutrino interacted with an electron in the fluid, the sensors would detect it.
Behind the scenesEdit
The neutrino is a subatomic particle that has no electric charge and travels close to the speed of light. Over time it oscillates through three "flavors", the electron, muon, and tau neutrino.