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Raymond Davis Jr. at Homestake Mine, South Dakota, in 1966, where he carried out experiments nearly 1 mile underground.
Photo: Courtesy of Brookhaven National Laboratory
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9 (of 9)
The Homestake mine tank that was used in the solar neutrino experiment was 20 feet in diameter and 48 feet long, and held 100,000 gallons of perchloroethylene. It was located 4,900 feet below ground surface.