Sinds de laatste tijd meer en meer gegevens binnen komen over de manen van Saturnus, blijkt dat deze gegevens de onderzoekers steeds meer verbazen over de natuurwetenschappelijke wetten die men aantreft.
Hier een voorbeeld:
Wind, rain and volcanism and tectonic activity all seem to play a role in shaping Titan's surface.
One scientist even sees a way that life could survive on the freezing world.
"Titan is perhaps the most Earth-like place in the Solar System other than Earth, in terms of the balance of processes," says Jonathan Lunine, of the University of Arizona, who is an interdisciplinary scientist for Cassini-Huygens.
"Wind-driven processes, river channels, evidence of rain, possible lakes and geological features that may have to do with volcanism and tectonism."
Different chemistry
But the chemistry that drives these processes is radically different between the two worlds. For example, methane seems to perform many of the same roles on Titan that water plays on Earth.
Dr Lunine believes that Earth and Titan both have similar processes occurring because they occupy "sweet spots" in the Solar System. Being in one these spots requires striking a balance between size, or mass, and distance from the Sun.
To demonstrate the idea, Dr Lunine considered three planets in the inner Solar System: Venus, Earth and Mars.
The mass of a body corresponds to an ability to sustain heat flow from its interior, while distance from the Sun is correlated with the ability to retain liquid water, a driver of geological activity on Earth.
Venus is about the same size as Earth. But it is so close to the Sun that any water it had must have boiled off. As such, there is no hydrological cycle and no tectonic activity, says Lunine.
Mars is distant enough from the Sun to retain water. But its small size caused it to cool quickly, turning water to ice and ending large-scale geological activity. Earth occupies an intermediate position - the "sweet spot".
The researcher then turned to three bodies in the outer Solar System: Ganymede, Titan and Triton. The chemistry is different, but similar principles apply.
Jupiter's moon Ganymede, the closest of the three to the Sun, is similar in size to Titan, but lacks the methane and nitrogen that drive liquid processes on the saturnian moon: "It's a kind of baked out version of Titan," said Lunine.
Neptune's moon Triton, much further from the Sun than both Ganymede and Titan, possesses methane and nitrogen. But its small size caused them to freeze, ending any prospect of geological activity.
Scientists have been revealing new details about Titan at the meeting in Cambridge. Ralph Lorenz of the University of Arizona, said that the river channels and flows on Titan are fashioned by "monsoon" events.
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