Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Titanscape on 18/09/2006 08:57:24
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I watched a documentary on Titan. Nitrogen and methane forms oils in the atmosphere. It is so cold the water never melts and Huygens landed in clay of fine ice and methane liquid. There is a cryo-volcano erupting subzero liquid water mixed with ammonia. This only freezes at about minus 100 degrees. I think Celsius. So it is thick and oozes out alike lava.
Titan is thought to be alike the earth billions of years ago, with life chemistry, but is too cold for it to progress at all.
Are there any other sources of info on Titan?
Titanscape
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Google the Cassini Huygens mission on both the NASA and ESA sites there's heaps of information and pictures.
Learn, create, test and tell
evolution rules in all things
God says so!
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Google the Cassini Huygens mission on both the NASA and ESA sites there's heaps of information and pictures.
Learn, create, test and tell
evolution rules in all things
God says so!
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IMO, the best space exploration project so far. Are they still looking for ethane?
Another semi-related question: Why do scientists all seem to assume that life in other worlds will be based on our chemistry? If we see weather cycles possible at different temperatures with different compounds, why not have ecosystems based on whatever compound is near it's triple point on the world's surface?
Maybe even hot worlds with bismuth oceans complete with icebergs floating on top. (If I remember corectly, bismuth also expands as it solidifies from liquid, maybe it was another element)
Anyway, I'm just trying to say that maybe life on other planets will be further removed from our assumptions than we generally imagine. Or more likely, we will never know, since this foreign life is so far from us.
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Way back in the days of my undergraduate studies we were asked to think about, and then write about, potential life-forms based on a different bio/chemistry from that on earth.
Gaia xxx
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Sounds like an interesting assignment. Care to share a tiny bit of what you came up with? Maybe something Phosphorus based, instead of Carbon? Why am I capitalizing so many words?
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There have been many serious papers and books written on the potential of other life chemistries. Although most of the ones I know date from the 50's and 60's. I havent seen any recent ones. The most likely alternative appeared to be silcion based. The chemistry of carbon is so many orders of magnitude more complex than any other element I think that nowadays it is considered to be unlikely that any other basic chemistry will provide the necessary complexity.
Learn, create, test and tell
evolution rules in all things
God says so!
-
IMO, the best space exploration project so far. Are they still looking for ethane?
Another semi-related question: Why do scientists all seem to assume that life in other worlds will be based on our chemistry? If we see weather cycles possible at different temperatures with different compounds, why not have ecosystems based on whatever compound is near it's triple point on the world's surface?
Maybe even hot worlds with bismuth oceans complete with icebergs floating on top. (If I remember corectly, bismuth also expands as it solidifies from liquid, maybe it was another element)
Anyway, I'm just trying to say that maybe life on other planets will be further removed from our assumptions than we generally imagine. Or more likely, we will never know, since this foreign life is so far from us.
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Way back in the days of my undergraduate studies we were asked to think about, and then write about, potential life-forms based on a different bio/chemistry from that on earth.
Gaia xxx
-
Sounds like an interesting assignment. Care to share a tiny bit of what you came up with? Maybe something Phosphorus based, instead of Carbon? Why am I capitalizing so many words?
-
There have been many serious papers and books written on the potential of other life chemistries. Although most of the ones I know date from the 50's and 60's. I havent seen any recent ones. The most likely alternative appeared to be silcion based. The chemistry of carbon is so many orders of magnitude more complex than any other element I think that nowadays it is considered to be unlikely that any other basic chemistry will provide the necessary complexity.
Learn, create, test and tell
evolution rules in all things
God says so!
-
If we wish to argue that carbon is uniquely qualified as a basis for life by reason that it is the most polymeric of elements, then we must probably concede that life can exist only within a limited temperature range. That assumes that the basis for life is chemistry as we know it. However, a planet might be inhabited by beings which are very dissimilar to us, e.g., robots. Robots as we understand that term are based more on iron, aluminum, copper, and silicon than on carbon. Of course, a robot almost by definition is not a living thing. However, it could resonably substitute for a living thing if it could be made to satisfy certain characteristics of living things. What would these be? Well, it would have to use food, grow, reproduce, and be capable of functioning toward some purpose within a habitat. Of these qualities, growth and reproduction are the most problematic. Robots cannot have babies -- or can they? If they could, and had one other ability, they could be used in a most useful astonautical manner: advance troops to prepare a planet for human visitation; or to function there indefinitely in his stead. The one additional quality is independent intelligence.
Actually, the intelligence issue may be the most critical. The reproduction of robots after their kind can be reduced to a manufacturing operation. Robots can run factories which will produce additional robots. What is needed to do this, however, is intelligence which can manage the process without human intervention. This goal may be difficult to achieve but possible. Once manufactured, the robots must have some overall guidance of their collective function, to prevent chaos from setting in, and to achieve whatever mission they have been sent to perform.
A society of robots, like of lhumans, would require infrastructure: mines, power, transportation, chemical manufacturing, etc. On the basis of all this, the society of robots would repair and/or manufacture new members of their class as needed, and would manage all this, and would, depending on mission, construct and operate facilities that mankind might one day use for visiting and working upon the planet.
Is all this possible? Probably. How soon might it occur? I will let someone else try to answer that one.
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If you wanted to construct a form of life that functioned at very low temperatures there is very limited energy, so it may be based on much weaker bonds - instead of breaking covalent bonds to rearrange molecules, could you conceivably have a whole chemistry based on van de Waals interactions between preexisting molecules. Essentially using molecules the way we use atoms...