http://saturn.jpl.nasa.gov/multimedia/flash/Enceladus/enceladus.html
The special interest in this little moon began in 2005, when Cassini observed huge jets of vapor and particles coming from parallel cracks on Enceladus’ surface. Cassini obtained a spectrogram of the material in one of the plumes by sampling the light from a star as it passed behind the plume. To the amazement of scientists, the plume was loaded with water vapor and other chemicals necessary to produce life. Not only that, but the cracks from which the geysers were coming, nicknamed “tiger stripes,” were actually deep valleys providing protected areas where nature could perform the delicate chemistry of forming life. As you can imagine, Enceladus has been the object of intense scrutiny ever since.
One of the main questions that are being asked is, where’s the water coming from? Since the initial discovery, scientists have been tossing around the interesting idea that there may be large amounts of water beneath the surface of Enceladus. If this turns out to be true, there are further questions: just how much water, and how deep is it? There is even the tantalizing possibility that Enceladus may have an internal ocean, which would be an even better place for life to start than the tiger stripes ... Full Article
Source:
http://2012-comet.com/astronomy/evidence-grows-for-an-ocean-inside-saturns-moon-enceladus/