Two Moons of Jupiter and Saturn May Have Oceans Beneath Icy Exteriors

Alexandria, Va. - It now appears that, of the many moons of Jupiter and Saturn, two of them may have oceans beneath their icy exteriors. Scientists studying Jupiter’s moon Ganymede - the largest moon in the solar system and the only one with its own magnetic field, which frequently sparks aurorae - used the Hubble space telescope to detect ultraviolet light emitted by the aurorae, which were less active than expected, given the moon’s magnetic field. Researchers propose the field is being counteracted by an electrically conductive saltwater ocean beneath the crust. In a separate study, researchers analyzing gravitational measurements of Saturn’s moon Enceladus discovered evidence for a body of water about 10 kilometers thick beneath up to 40 kilometers of ice.

For more on how scientists identified lunar bodies with potential oceans, read the free article in the August issue of EARTH Magazine.

EARTH Magazine brings readers exclusive and groundbreaking stories from the geoscience community in its August 2015 digital issue, and the July/August 2015 print issue, both available from www.earthmagazine.com. Stories include new research that widens the dispersal of humans into Arabia, a comment from scientist Rodney Viereck on space weather forecasting, and feature stories on the future of the U.S. icebreaker fleet and the role the World Endurance Championship is playing in innovating energy technologies for the auto industry.