Astronomers have traced a high-energy neutrino to its cosmic source for the first time ever, solving a century-old mystery in the process.
Neutrinos are nearly massless subatomic particles that have no electric charge and therefore interact rarely with their surroundings. Indeed, trillions of these “ghost particles” stream through your body unnoticed and unhindered every second.
Most of these neutrinos come from the sun. But a small percentage, which boast extremely high energies, have rocketed to our neck of the woods from very deep space. The inherent elusiveness of neutrinos has prevented astronomers from pinning down the origin of such cosmic wanderers — until now.