Saturn’s moon Enceladus may have underground global ocean

BBC : Over the past decade, data gathered by the Cassini probe have shown evidence of liquid water and vapor being vented from fractures at the south pole of Saturn’s moon Enceladus. But exactly where the water originated was not known. Researchers assumed it was coming from some hidden reservoir but had no idea of its size. After studying the moon’s rotation based on measurements of benchmark points across its surface, Matthew Tiscareno of the SETI Institute and colleagues have found that Enceladus wobbles slightly. That wobble, they say, indicates that the moon’s surface and core are not rigidly connected but more probably are separated by some liquid mass that is far more extensive than previously thought. Because of the presence of salts and organic molecules, detected earlier by Cassini,and now the possibility of such a global ocean,Enceladus could be a prime candidate for a future space mission.