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I have a burning need to know stuff and I love asking awkward questions.

Saturday, December 05, 2009

Icy moon's lakes brim with hearty soup for life

by David Shiga for New Scientist

23 November 2009

Saturn's frigid moon Titan may be friendlier to life than previously thought. New calculations suggest Titan's hydrocarbon lakes are loaded with acetylene, a chemical some scientists say could serve as food for cold-resistant organisms. At about -180 °Celsius, Titan's surface is far too cold for liquid water. But two pairs of scientists proposed in 2005 that alien organisms might live instead in bodies of liquid hydrocarbons on the frigid moon. They suggested such organisms could eat acetylene that falls to the surface after forming in the atmosphere, combining it with hydrogen to gain energy. Since then, Cassini has spotted dozens of lakes on Titan's surface, thought to be made of a mixture of liquid ethane and methane. But since no probe has directly sampled them, no one knows how much acetylene they might contain. An estimate made in 1989 suggested bodies of liquid hydrocarbons on Titan would contain a few parts in 10,000 of acetylene.

But an updated estimate based on data from the Cassini-Huygens mission to Saturn now suggests the lakes contain much more food for any hungry alien life-forms that might be present. The new calculations were made by a team of scientists led by Daniel Cordier of the Ecole Nationale Supérieure de Chimie de Renne, France. Data from the Cassini spacecraft and the Huygens probe, which parachuted to Titan's surface in 2005, helped Cordier's team re-calculate the lakes' likely composition. This depends on factors like a lake's temperature, which affects how easily chemicals will dissolve in it, and the rate various chemicals are produced in the atmosphere and rain onto the surface. The team found that acetylene would be hundreds of times as abundant as the previous estimate, making up one part in 100 of the lake's content. "Having about a per cent of acetylene is potentially interesting from the life point of view," says team member Jonathan Lunine of the University of Arizona in Tucson. The idea of acetylene-eating organisms on Titan is "highly speculative" but intriguing, he says.

"I think the results are very exciting and further support the possibility for life on Titan," says Dirk Schulze-Makuch of Washington State University in Pullman, one of the scientists who proposed the possibility of acetylene-eating life in 2005. "Titan should be one of the two top targets for future astrobiology missions, the other being Mars." But Tetsuya Tokano, a Titan researcher at the University of Cologne in Germany, says the exact amount of acetylene may be less important than other properties of the lakes that remain unknown, such as the existence of currents to keep them well-mixed. Tokano pointed out in a recent study that without mixing, hydrogen and acetylene would stay in separate layers of the lakes, limiting reactions between them that might otherwise power exotic organisms.

[It does continue to amuse me that theists in particular seem to pour scorn on the idea that life could have evolved independently on other worlds. Although we have no hard evidence of this, the amount of circumstantial evidence and well founded speculation continues to grow. It seems increasingly likely that life exists somewhere other than on Earth and that it emerged and evolved there independently of this world. Once this is firmly established I think that many theists will have to examine their belief in unique creation. How they will incorporate alien life into their belief systems I cannot even began to speculate on but I do suspect that when we do find life elsewhere it will yet again undermine our unique place in the universe and maybe, just maybe, make us a little more humble.]

4 comments:

Mike aka MonolithTMA said...

Cool!

The shape of the image makes it look like one of the rings from Halo.

http://img53.imageshack.us/i/halopc_dangercanyon.jpg/

Scott said...

I don't understand your argument. If there is a god who created a vast and potentially unending universe, it stands to reason that this same god would have created life in more than one location if life is something this god values. I don't understand why existence of life on other planets would qualify as some sort of evidence that there is no god.

CyberKitten said...

scott said: I don't understand why existence of life on other planets would qualify as some sort of evidence that there is no god.

It shouldn't. But I've heard theists imply (or infer) that the universe was created for us - and that it was exclusively created for us to expand into basically without the need to fight for every inch of extraterestrial soil. Life, and especially intelligent life, on other worlds would imply that the universe wasn't created just for us (or even created at all) which would cause some people to question some basic assumptions they might hold.

Personally speaking the existence of other lifeforms should not cause any theists the loss of a single nights sleep. If God is interested in the promotion and welfare of *all* life then any reasonable believer should expect the universe to be teeming with life rather than the reverse - but I still think that when we do find life (and I do think it'll be when rather than if) it will come as a decided shock to some people.

Laughing Boy said...

If God is interested in the promotion and welfare of *all* life then any reasonable believer should expect the universe to be teeming with life rather than the reverse...

I don't think terrestrial (or extraterrestrial) life, per se, is a high priority for God. At least I doubt if it's so much of a priority that he would want the universe to teem with it. From what we've learned so far it doesn't seem to be the case.

Personally, I agree with Scott that the existence of rational life on other planets is not a threat to theism or Christianity in particular (where does the Bible God did not create other life elsewhere?), nor is it boon to atheism.

On the other hand it would raise interesting theological questions since I believe the same system would hold for morally responsible beings wherever they may be.

On the other, other hand, the anthropomorphic principle doesn't seem too far fetched to me and I would indeed have to do some serious thinking if ET life is found (or finds us). But I don't see how that rethinking would call God's existence into question.