HAWC (IMAGE) University of Maryland Caption The HAWC Observatory, perched next to a volcano at an altitude of 13,500 feet, uses its 300 massive water tanks to scoop up the products of high-energy particle collisions happening in the upper atmosphere. Credit Jordan Goodman 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.