Grand Prismatic Spring in Yellowstone (IMAGE) U.S. National Science Foundation Caption This is Grand Prismatic Spring in Yellowstone; such hot pools often bubble with undiscovered microbes. Credit NPS 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.