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Titan Occupies A Solar System Sweet Spot
SocietyoftheFist writes "From an article on the BBC website, scientists have determined that Titan occupies a 'sweet spot' much like Earth. Venus is the same size as Earth but too hot so water boiled off long ago ending most geologic processes. Mars is too small to generate enough heat to keep water from freezing so it too slowed down geologically. Titan is much like the Earth with winds, rains and tectonic forces but instead of water it has an abundance of methane. Methane is liquid at the temperatures found in Titan's atmosphere and replaces water in the equation."
Cow mutilations are obviously the result of partying Titans down here huffing cows. Their parents probably don't have a clue what their up to.
"Academicians are more likely to share each other's toothbrush than each other's nomenclature."
Cohen
Titan moon occupies 'sweet spot'
By Paul Rincon
BBC News science reporter, in Cambridge
Wind, rain and volcanism play a big role on Titan
Earth and Saturn's moon Titan show striking similarities because both occupy "sweet spots" in our Solar System, researchers have said.
Many processes that occur on Earth also take place on this moon, say scientists participating in the US-European Cassini-Huygens mission.
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.
Titan is perhaps the most Earth-like place in the Solar System other than Earth
Jonathan Lunine, University of Arizona
"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.
'Catastrophic rains'
It takes a relatively long time for methane to build up to a point where it can rain down on Titan's surface. Scientists, therefore, think rains are only occasional, but catastrophic, when they occur.
Evidence also suggests Titan is constantly being resurfaced by a fluid mixture of water and ammonia spewed out by volcanoes and hot springs, explaining why Titan is not littered with impact craters like its neighbours
Many processes that occur on Earth also take place on Titan
A surface feature called Ganesa Macula may show just such a flow emanating from a volcanic crater.
The moon's icy surface is also covered with a film, or patina, of organic compounds, Cassini-Huygens data show.
One researcher has even proposed a way for life to survive on the giant Saturnian satellite. It is too cold for organisms to survive
No smoking allowed on Titan then? Or is there no oxygen anyway?
jouwnieuws!