HAWC Panorama Nov 2017a (IMAGE) University of Maryland Caption The High-Altitude Water Cherenkov Gamma-Ray Observatory (HAWC) is a detector designed to look at gamma-ray emission coming from astronomical objects such as supernova remnants, quasars and rotating dense stars called pulsars. Located roughly 13,500 feet above sea level near the Sierra Negra volcano in Mexico, the detector is composed of more than 300 tanks of water, each about 24 feet in diameter. When particles strike the water, they produce a shock wave of blue light called Cherenkov radiation. Special cameras in the tanks detect this light, allowing scientists to determine the origin of incoming gamma rays. Credit Jordan Goodman/University of Maryland 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.