Birthplace of Solar Neutrino Physics

20 June 2003

This photo from 1966 shows the construction of the tank used in the solar neutrino experiment in the Homestake gold mine. The tank, 20 feet in diameter and 48 feet long, held 100,000 gallons of perchloroethylene and was located 4,900 feet below ground surface. The experiment found fewer neutrinos than expected, and hence gave rise to the famous "solar neutrino problem" - which only recently appears to have been solved. The experiment was turned off in 2001, when the mine closed, but the company that owns the mine continued to pump water from the mine while a group of scientists negotiated hard to establish a world-class National Underground Science and Engineering Laboratory - NUSEL - in the mine. Last week - despite lobbying by Nobel prize winners - on 10 June 2003, the company stopped pumping water, and the future of this important scientific seems doomed.

Credit: Brookhaven National Laboratory