Perhaps the most surprising water worlds are the five icy moons of Jupiter and Saturn that show strong evidence of oceans beneath their surfaces: Ganymede, Europa and Callisto at Jupiter, and Enceladus and Titan at Saturn. Scientists using NASA's Hubble Space Telescope recently provided powerful evidence that Ganymede has a saltwater, sub-surface ocean, likely sandwiched between two layers of ice.
In this artist’s concept, the moon Ganymede orbits the giant planet Jupiter. The Hubble Space Telescope observed aurorae on the moon generated by Ganymede’s magnetic fields. A saline ocean under the moon’s icy crust best explains shifting in the auroral belts measured by Hubble.
More: The Solar System and Beyond is Awash in Water
Image Credit: NASA/ESA via NASA http://ift.tt/1a23AT3 Amazing.