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Hints of Life Found On Saturn's Moon Titan
Calopteryx writes "New Scientist reports that in 2005, researchers predicted two potential signatures of life on Titan. Now, thanks to research done with the help of the Cassini spacecraft, both have been seen, although non-biological chemical reactions could also be behind the observations. NASA's writeup has further details: 'One key finding comes from a paper online now in the journal Icarus [abstract] that shows hydrogen molecules flowing down through Titan's atmosphere and disappearing at the surface. Another paper online now in the Journal of Geophysical Research maps hydrocarbons on the Titan surface and finds a lack of acetylene. This lack of acetylene is important because that chemical would likely be the best energy source for a methane-based life on Titan, said Chris McKay, an astrobiologist at NASA Ames Research Center, Moffett Field, Calif., who proposed a set of conditions necessary for this kind of methane-based life on Titan in 2005. One interpretation of the acetylene data is that the hydrocarbon is being consumed as food. But McKay said the flow of hydrogen is even more critical because all of their proposed mechanisms involved the consumption of hydrogen.'"
When I was in Jr. High, my science class had an assignment where we had to make-up a life form, based on the planet chosen's conditions and mine was Saturn. Of course my design was completely ridiculous, but the idea was pretty much close to what they're saying about Hydrogen consumption. This is pretty cool...I *heart* Saturn. "Pro'lly 'cuz it gots money with all them rings it has!" lol =P
...or possibly not.
SJW: Someone who has run out of real oppression, and has to fake it.
The worst thing that could possibly happen for any form of life anywhere would be its discovery by us.
...The Sirens of Titan.
What a fool believes, he sees, no wise man has the power to reason away.
http://en.wikipedia.org/wiki/Titan_Mare_Explorer (hopefully not postponed to be part of http://en.wikipedia.org/wiki/Titan_Saturn_System_Mission )
Titan, and Saturn system generally, is a really big thing for our distant future. People like to imagine the colonisation of Jupiter system, but the radiation belts there make it not exactly feasible; only Callisto out of 4 big moons might be fine. Saturn doesn't have this problem; is still decently close and with huge system of moons.
Discovery of life on Titan might of course complicate things...OTOH, with it (if any) being probably so vastly different, there's little risk of crosscontamination in either direction.
One that hath name thou can not otter
It sounded like it was referring to heretofore unknown kinds of life that use completely different chemical processes than we see on earth, with the possible exception of really weird stuff that you find at the bottom of the ocean. Nothing that would have gotten onto our probe, in any case.
I think you misunderstand. The mechanisms that would cause life to consume the substances that are 'missing' are totally alien to life as we know it, but fit the model for methane based life very well. It could well be that there are non-biological chemical processes doing it, but the odds of it being from any contamination from Huygens is astronomically remote. Hugyens was also very, very carefully sterilized. Granted, a microbe or two might have made it to Titan, where it would most likely die rather than reproduce.
I do see your point and we need to continue to be careful, but I see nothing in these findings that makes the Hugyens discussion at all relevant to this story.
It would be fairly easy to tell earth based contamination from native stuff. For starters, I'm not aware of any bacterium that you would find on the surface of the earth that eats hydrocarbons in that way and can live in those conditions. Below the artic ice? maybe... but in a clean room in texas? not likely.
the preceding post was not spell checked... suck it.
I, for one welco...ah, screw it.
Methane itself is odorless. I suppose you could be referring to the aromatic compounds that methane-based life might excrete. You're probably just going for the cheap methane is farts joke. Yeah, imagine a Beowulf cluster of those!
What a fool believes, he sees, no wise man has the power to reason away.
Breathing hydrogen basically works in the opposite direction of terrestrial biochemistry. The proposed organisms are breathing hydrogen and presumably fixing it to something (say, oxides they've eaten) rather than the other way around as for Earth life.
And even if it was possible, Huygens could not have contaminated things to such a degree as to affect widespread atmospheric phenomenon.
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The probe was sterilized, if I recall correctly. So it shouldn't be an issue.
Keep in mind that in the long history of the solar system it's likely that material blasted off the earth by an impact event or events has made its way to the surface of Titan. So Titan may have already been contaminated with life from earth.
I have a pretty good suspicion that most life on Earth, even the extremophiles, would have a rather hard time living on Titan. The temperatures are extremely low, the solar energy and even Saturn's energy are much less combined than on Earth. The kind of biochemistry would be quite different than found here. I'm not saying it's entirely impossible, but I think a planet like Mars would be far more likely to be able to harbor certain hardy organisms from Earth than a place like Titan. My understanding is that on a world like Titan, the solvent would be something like ammonia or an ammonia-water mixture, so we'd see considerably different organic chemistry that would likely kill of anything we left behind in a really big hurry.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Unless we've unwittingly invented terraforming? :p
Remember to maintain your supply of
Easy, drifting anything into the void contaminates the void.
The original printing of the book 2001, they went to Saturn. In the film they went to Jupiter. After seeing the film Clarke thought that made more sense, so he wrote the sequel based on the film, not his book.
http://en.wikipedia.org/wiki/2001:_A_Space_Odyssey_(novel)#Differences_from_the_film
As far as I care, it's fair game as long as it isn't Europa. We should attempt no landings there.
Genocide Man -- Life is funny. Death is funnier. Mass murder can be hilarious.
Titan is a young celestial body - with its own dense atmosphere and the only body until now in the solar system that has surface liquids apart from us.
Sure it can be hypothesized that since Titan is young - it probably is taking a course that Earth took millions of years ago. With the distance from Sun rendering it cold and the fact that it orbits Saturn being the primary differences.
Of course finding Life would be an enormous discovery. But if we start with what we already know - that Organic reactions are taking place on Titan's surface, and that it is a giant Organic Soup -- It gives us a huge interesting laboratory to study and experiment!
We can even direct Titan's course of life by controlled introduction of earth's anaerobic life on its surface -- since we already know a hypothesis on how our own Earth's atmosphere has evolved into the current air composition -- we can *test* and use those theories to change Titan's atmosphere, in turn not only validating our theories, but may be making Titan inhabitable like Earth!
Exciting to say the least! If only we humans can, just for a second -- stop bickering amongst ourselves and look outwards to this possibility!!
I must be misinterpreting your comment. Can you explain how crashing a probe into a celestial body has LESS contamination risk than just letting it drift off into the void?
Generally, they crash it into a celestial body that has no capability to support life and, such as the case of Jupiter, is hostile to the biological processes of what could possibly contaminate it.
No life from Earth will survive in Jupiter's atmosphere. The pressure is... extreme beyond that of the extreme on Earth.
The pressure there would be 10,000 times greater than the pressure at the deepest point in Earth's ocean. 10,000,000 Earth Atmospheres compared to 1,000 in the Marianas Trench.
Then you have the temperature. The hottest spot on Earth (the core) is about 7300K. On the liquid 'surface' of Jupiter, it is 10,000k. The most extreme of the thermophiles on Earth live in an area less than 400k. The core of Jupiter is hotter than the surface of the Sun.
If you find me something that can survive 10,000k temperatures and 10 million atmospheres I'd bow down to my new overlord.
Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
If it uses DNA or RNA (quite unlikely) then I guess that contamination is possible. But since we'd want to totally sequence whatever replicator molecule it used, it would be reasonably easy to determine whether contamination is even a reasonable hypothesis.
Remember, all life on this planet is related to a measurable degree. If it's related, then we can figure out what it's most closely related to, and how long ago it diverged. (Remember, when the proto-moon collided with the earth it quite likely emitted fragments that went that far. But we could measure even that distant a relationship, albeit with less certainty.)
But it's most likely that whatever molecule it uses for a replicator would be something not related to our nucleic acids. For one thing, the major solvents appear to be non-polar rather than polar, so anything water-based would be insoluble, where things that are lipid based would tend to be soluble. Also, the reaction rate is very temperature dependent, so it would be probable that the major chemicals of life on Titan would be unstable at STP (standard temperature and pressure).
I think we've pushed this "anyone can grow up to be president" thing too far.
Life doesn't have to "get" there. If the chemistry is right, it will start itself.
When our name is on the back of your car, we're behind you all the way!
The main reason they sterilize their probes is to get "cleaner" data and no risk of contamination of future probe readings. After all, one cell is all they need to find. Any false-positive will be a disaster that they'd never live down.
not to mention contaminating other components of the same probe.
at least the discovery that earth life flourished on a celestial body would be scientifically interesting. A space probe that did nothing but detect that it was self-contaminated prior to launch and can't provide useful data would be a total failure.
No one has a right to their *own* opinion. They have a right to the TRUTH.
Actually I don't think his is a bad point. First off, we DON'T understand the metabolisms of most microbes on earth: most CAN'T be cultured in a lab because of this, experimented with, etc. etc.: only a little subset of the entire known microbial biota are even available for us to research. Beyond this, however, the known range of things that microbes can eat is expanding beyond our wildest imaginings: and not just on the bottom of oceans. That's why we now have microbes to use to eat oil spills, nuclear waste, and even metals (ummm....iron and steal, yum!). Not kidding about the bacteria that eat metals, by the way, which incidentally...DO IT BY HYDROGEN AND ELECTRON EXCHANGES. There's all sorts of stuff that one can tell you haven't even considered from the comment you just made: you need to do more dreaming "dream[er]...".
P.S. bacteria have survived in the vaccum of space on the moon, so "[they] would most likely die" is also not a very informed statement. I don't mean to be too insulting here, just very frank about the state of knowledge on these things vs. what you wrote: that is rose to "5, Insightful" just demanded the bio nerd in me to respond.
Intelligent idiots are we. | Evil men do not understand justice.
I need to mention that the microbes known no earth, with all their various metabolisms, sometimes seem as though they really are from separate planets. That said, enver underestimate their abilities to swap genetic material and re-synthesize their machineries for different environments. Knowing this, "there should be little chance of confusion" isn't so reassuring: it already is just with the "earth" based life, even trying to figure out whether this or that is related to that or the other, where such and such came from, etc. (the so-called maps of microbial relationships are extremely pick-and-choosy, subjectively prioritizing one or another criterium over others depending on the values of the researchers, and often more in favor of various formulations of theories instead of the barest and hardest facts or most critical considerations: honestly it's practically impossible to get past the sheer amount of information, that's ever-increasing by magnitudes, in order to do better, but much better can be done, it's just that complicated and as I said, confusing). Oh, and this, http://science.slashdot.org/comments.pl?sid=1675560&cid=32465806http://science.slashdot.org/comments.pl?sid=1675560&cid=32465806
Intelligent idiots are we. | Evil men do not understand justice.
That seems like an Occam-worthy assumption, yes.
If you're like me (and most serious scientists, I gather) and believe life on Earth formed spontaneously, then it's reasonable enough to assume it can happen again. We have absolutely zero ideas how easy this is to happen, so there's no good reason to claim it can't be happening all the time.
If you're of a spiritual persuasion and believe life was kick started by some ghost or other, then you'll probably have to admit that there's no reason your omnipotent-being-of-choice doesn't do the same thing on every planet that it'd work on. Most holy texts are scrupulously silent on the subject of extraterrestrial life, so we mortals are left to just guess.
In short, it seems more likely that it'd happen again than not. And for all we know, Titan is paradise incarnate for methane-drinking, hydrogen breathing life.