Neutrino Detector (IMAGE) Princeton University Caption The Princeton University scientists and others in the Borexino Collaboration have detected geoneutrinos at the Gran Sasso National Laboratory of the Italian Institute of Nuclear Physics. The discovery could explain how reactions taking place in the planet's deep interior affect events on the surface. This stainless steel sphere is part of the neutrino detector used in the project, located nearly a mile below the surface of the Gran Sasso mountain about 60 miles outside of Rome. Credit Paolo Lombardi INFN-MI Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.