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Cassini Finds Evidence For Ocean Inside Titan
Riding with Robots writes "NASA reports that by using data from the Cassini probe's radar, scientists established the locations of 50 unique landmarks on the surface of Saturn's planet-size moon Titan. They then searched for these same lakes, canyons and mountains in the data after subsequent Titan flybys. They found that the features had shifted from their expected positions by up to 30 kilometers. NASA says a systematic displacement of surface features would be difficult to explain unless the moon's icy crust was decoupled from its core by an internal ocean, making it easier for the crust to move. If confirmed, this discovery would add to the growing list of moons in the solar system that are icy on the outside and warm and liquid inside, providing potential habitats. We've previously discussed Titan's hydrocarbon lakes and potential cryovolcano."
Life ON gas giants seems like a big NO with what we currently know about the conditions required for life to emerge. But life around gas giants, on their moons seems plausible.
What I'd like to know (read: what I'd like some slashdotter with the required know-how explain to me) is why are these moons hot on the inside, possibly hot enough for water ice to turn into liquid water. It's so incredibly far away from the sun. Is this caused by their size and subsequent internal dynamics?
Also, aren't these moons constantly bombarded with radiation from their host planet's powerful magnetic field? Must be rough for aliens.
"it sure would be interesting to send a probe in to it and see what we can discover."
We have sent The Huygens Probe Before, but it was not designed to look for an underwater ocean. Lets hope they return with somthing else.
While it is very likely that the interiors of a couple moons in the solar system have subsurface liquid oceans, that does not indicate high enough temperature at depth to consider the interior warm or hot or capable of supporting life. Over geologic time these subsurface liquids (which are thought to be predominantly H2O) have more likely formed through interaction with surrounding rock/metal. As H2O reacts with its surroundings and incorporates various impurities (salts, ammonia, organic molecules) into its structure the melting point is decreased to the point that a liquid or fluid condition is possible at significantly lower temperatures. Although in the case of Ganymede (Jupiter's fourth moon), which posses an internally generated magnetic field, a dynamo action similar to Earth's core may exist providing heat. Whether this is the case on Titan is yet to be determined. The massive amounts of organic components there make it harder to determine if there is an internal heat source or if the mixture of organic compounds are naturally stable at those conditions creating the lakes and cryovolcanoes previously mentioned.
Not to be rude, but actually this is incorrect. At low pressures there is some odd behavoir, but on a planetary scale the melting point of water increases with increasing pressure. Ice has several different crystal structures called polymorphs that change as pressure increases. Each requires greater and greater temperature to melt. This is a good page on the water molecule and its behavoir: http://www.lsbu.ac.uk/water/index2.html.
I suspect I was not alone.
It is still correct to say that it would be interesting to send a probe into it, though.