NASA confirms there's an ocean on Jupiter's moon Ganymede
The largest moon in our solar system is hiding an ocean under its surface, according to observations made with the Hubble Space Telescope. Aurorae spotted by the telescope, confirmed the long-standing theory, and the findings were announced during a NASA teleconference this morning. The news comes just a day after we found out that Enceladus, an icy moon of Saturn, likely has hydrothermal activity in its own subsurface ocean.
Scientists have speculated since the 1970s that Ganymede could have such an ocean. Until now, though, the only evidence was collected during brief flybys with the Galileo spacecraft in the early 2000s. That left too much ambiguity in the data for NASA scientists to comfortably confirm the ocean’s existence.
Source:: The Verge