Although it sounds like science fiction, one of Saturn’s moons has been suspected to be almost entirely oceanic for a while. NASA, however, has found rather dramatic proof that the entire moon is an ocean.
How? Wobbling. As we all know, water acts differently than solids in the presence of gravity; the more water a planet has, the more likely it is to “rock” back and forth in its orbit. Scientists working on the data from Cassini, the probe currently exploring Saturn, studied seven years’ worth of images and found that Enceladus just wobbles too much for it to be anything other than water surrounding a rocky core, with a thin sheet of ice over it.
The theory is that Saturn’s gravity distorts the core, warming it and melting the ice around it. The heat is so intense it melts all but a relatively thin rind of ice that completely encases the planet. Enceladus’ south pole vents the pressure, and you have what amounts to an ocean moon.
Here’s where it gets interesting: The geysers at Enceladus’ south pole are rich with organic molecules, the “prebiotic soup” that may have led to life on Earth. And we’ve learned that life can exist in situations much like Enceladus’ environment. It seems likely that alien microbes, even possibly alien aquatic life, might be living under the crust of Enceladus.
We may not know for a while; needless to say, Saturn is a bit down the list of places we’re going to send people to. But it’s a tantalizing hint that alien life might be closer than we think.
(via PopSci)