The IceCube facility may have caught evidence of seven elusive ghosts. There is nothing supernatural about them, however. They're "ghost particles," or...
A view of a facility with white pillars on either side, attached to a metal structure with stairs. It's in a snowy area; the sky is very blue. An inset shows a diagram of how IceCube works. Astronomers using the IceCube observatory, which is buried deep within the ice of the south pole, have detected seven elusive and exotic "ghost particle" candidates as they streamed through Earth. The signals suggest these particles are astrophysical tau neutrinos; they act as important messengers between powerful, high-energy celestial events and us. Neutrinos are charge-less and nearly mass-less particles that blast through the cosmos at speeds approaching that of light. Oddly enough, because of those parameters, neutrinos barely interact with anything. In fact, around 100 trillion of them pass through our bodies every second. We just can't tell. If you were a human-size neutrino detector, you would have to wait about 100 years for a neutrino to interact with a particle in your body. It is thus for good reason that neutrinos are nicknamed "ghost particles." High-energy neutrinos from cosmic sources at the edge of the Milky Way are called "astrophysical neutrinos," and they come in three flavors, or generations: Electron neutrinos, muon neutrinos and tau neutrinos. All of these phantom particles are incredibly elusive, as you may expect, but nailing them down is IceCube's mission. In 2013, the observatory made its first detection of astrophysical neutrinos, and now it appears to have detected astrophysical tau neutrinos in particular which could serve as an entirely new type of cosmic messenger. Related: A nearby supernova could reveal the secret lives of ghostly neutrinos. Here's how. "The detection of seven candidate tau neutrino…