Enceladus has a sub-surface ocean. This is cutting-edge science. We have both sides trying to get more evidence and figure out what's going on with this weird moon. Yesterday, NASA released a new piece of evidence that may tip the scales.
A team from the Southwest Research Institute in Texas, used the spectrometer on Cassini to find ammonia in the plumes that are shooting out of Enceladus's surface. The interesting thing about ammonia is that it is an antifreeze. According to the NASA report ammonia can allow the water to remain a liquid at temperatures as low as -143 degrees Fahrenheit. Hunter Waite, the Cassini Ion and Neutral Mass Spectrometer Lead Scientist from the Southwest Research Institute in San Antonio said "Given that temperatures in excess of 180 Kelvin (-136 degrees Fahrenheit) have been measured near the fractures on Enceladus where the jets emanate, we think we have an excellent argument for a liquid water interior."
This is a really interesting result and has powerful implications. I predict, however, that this will not end the debate. We really need some piece of definitive evidence. I hope that there is a liquid ocean because that opens up the question of whether or not there is life on Enceladus. The moons of the outer planets are exciting places that I am sure have many more surprises in store. I can't wait to see what they are.