IceCube

How do you find something that isn't directly visible? That's the challenge faced by the team who developed the IceCube neutrino detector under the ice at the South Pole. Just as X-rays allow us to see bone fractures, and MRIs help doctors find damage to soft tissue, neutrinos will reveal new information about the Universe that can't be seen directly. The in-ice particle detector at the South Pole records the interactions of neutrinos, which are nearly massless sub-atomic messenger particles. Neutrinos are incredibly common (about 100 trillion pass through your body as you read this) subatomic particles that have no electric charge and almost no mass. They are created by radioactive decay and nuclear reactions, such as those in the Sun and other stars. Neutrinos rarely react with other particles; in fact, most of them pass through objects (like the earth) without any interaction. This makes them ideal for carrying information from distant parts of the universe, but it also makes them very hard to detect.