Ganymede (IMAGE) University of Washington Caption This satellite image shows white streaks across the surface of Ganymede, the largest of Jupiter’s moons. The discovery of new types of salty ice could explain the material in these streaks and provide clues on the composition of Ganymede’s ice-covered ocean. Credit NASA/JPL/JUNO Usage Restrictions No restrictions. License Public Domain 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.