Neutrinos are a type of particle that pass through just about everything in their path from even the most distant regions of the universe. The Earth is constantly bombarded by billions of neutrinos, which zip right through the entire globe, houses, animals, people - everything. Only very rarely do they react with matter, but the giant IceCube experiment at the South Pole can detect when there is a collision between neutrinos and atoms in the ice using a network of detectors.
