How was outer space created? What processes occur in suns and supernovae? What happens in black holes? Many of these fundamental questions that have long been the subject of research have close ties with the universe. Most our our knowledge about the universe has been gained by observing photons. These light quanta are produced in large quantities, are stable and are easily traced in a wide range of energy. Their spectrum also supplies detailed information about the chemical and physical composition of the source. Unfortunately, the extremely hot, dense areas that form the centre of stars, active galactic centres and other astrophysical energy sources are completely impermeable to photons. There is only one type of particle capable of helping scientists obtain more information about these highly interesting objects: the neutrino.
