Wednesday, March 02, 2005

277: Complex organic molecules forming spontaneously on Titan

news @ - Titanic complexity pleases planet scientists - Cassini beams back data on ammoniac lava and 'cat scratch' formations.:

When methane molecules are broken down by ultraviolet radiation that has penetrated the atmosphere, two of the fragments generated can potentially combine to form ethane. But the relative lack of ethane suggests that the fragments may be reacting further, for example, by combining with the nitrogen in the atmosphere.

Toby Owen, Cassini's interdisciplinary scientist for the atmospheres of Titan and Saturn, presented the results to the AAAS meeting. "The photochemistry goes further than the models suggested, to more complex things," he says. "Methane and nitrogen are being broken apart in the atmosphere and are forming larger molecules."

The chemistry may resemble that of the early Earth, before life began. "That has us very excited," Owen says. Huygens detected organic molecules at its landing site, but Owen says it is not yet clear how complex they are. He's not expecting to find life because, "It's much too cool." But he says we might find some of the precursor molecules of life frozen in the ice, forming a "primordial ice cream".
Maybe not life on Titan, but it's still possible, and this almost surely tells us about early conditions on earth.