A core collapse in the Milky Way will produce an enormous burst of neutrinos
in detectors world-wide. Such a burst has the potential to provide an early
warning of a supernova's appearance. I will describe the nature of the signal,
the sensitivity of current detectors, and SNEWS, the SuperNova Early Warning
System, a network designed to alert astronomers as soon as possible after the
detected neutrino signal.Comment: 3 pages, appearing in refereed proceedings of "Hotwiring the
Transient Universe 2007", eds. A. Allan, J. S. Bloom, R. Seaman, Astron.
Nachr. vol. 329, March 200