NEUTRINO ASTRONOMY ON THE 1 KM2 SCALE

We discuss sources of very high energy cosmic neutrinos, from the accelerators of the observed high energy cosmic rays to active galactic nuclei and dark matter particles trapped in the Sun. The survey leads to the conclusion that an area of 1 km2 is the natural scale of a future neutrino telescope. We subsequently review cost effective methods to commission such detectors emphasizing recent initiatives to use large volumes of the polar ice cap as a low-noise particle detector sensing the Cherenkov light from neutrino-induced muons. We describe the first encouraging results of a program mapping the optical clarity of polar ice at depths ranging from 200 m to 1 km. We also review detailed numerical simulations of an alternative technique which consists of detecting the GHz radiosignals generated by the neutrino-induced electromagnetic cascade in ice.