An observatory beneath the earth? Yes, it is in fact-true. The Sudbury Neutrino Observatory is not your ordinary telescope. The SNO was built in Ontario, Canada designed to detect neutrinos produced by fusion reactions in the sun. Located in the deepest part of the mine, the rock shields the detector from sonic rays.  The depth is necessary, reducing background signals from radioactive elements present in the mine dust-which would otherwise hide the very weak signal from neutrinos.

The Neutrinos pass through 1,000 tons of heavy water to produce flashes of light called Cherenkov radiation. The radiation is then picked-up by 9,522 ultra-sensitive photomultiplier tubes positioned around the 60-foot sphere. Plans are currently underway to replace the heavy water with something called liquid scintillator to upgrade the SNO.

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