Exomoon (IMAGE) University of California - Riverside Caption This image shows an Earth-like "exomoon" orbiting a gas giant planet in a star's habitable zone. Credit NASA/JPL-Caltech 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.