The Enriched Xenon Observatory 200 (image) California Institute of Technology Caption The Enriched Xenon Observatory 200 (EXO-200) is a neutrino experiment housed 2150 feet below ground in a salt basin at the Waste Isolation Pilot Plant (WIPP). The subterranean location isolates it from cosmic rays and other sources of natural radioactivity. Credit EXO/WIPP/SLAC Usage Restrictions None 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.