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Thread: Earth and conditions for life

  1. #1 Earth and conditions for life 
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    Hello!



    Many properties of our planets are claimed to be fine-tuned in the exact proportions to permit life emergence and its evolution:


    Earth's axial Inclination of 23°

    Moon stabilizing Earth's axis.

    Solar-system's perfect position in the Milky way.

    The presence of nearby galaxies

    so on...

    But, in spite of their important quantities, are these features really improbable to occur together in any planet of Universe except the Earth?


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  3. #2  
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    Think about how many planets exist in the universe. Although conditions for Earth seem to be perfectly tailored for life, these conditions are quite likely not unique to Earth. Probabilities are heavily in favor of the fact that favorable conditions elsewhere.


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  4. #3  
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    You also have to take into account that life as we know it requires these specific conditions. Had the conditions been different a different form or type of life may have evolved.

    We are looking at this from a perspective of, a fish in a tank. Sure the fish looks around and says, "Wow this was tailor made for me! If this glass wasn't here the water would fall out and I would die. If the air pump stopped working the oxygen levels would fall and I wouldn't get enough oxygen and die. All these things have to exist in order for me to live." What the fish doesn't know is that there are other fish, living in streams and lakes and the ocean that don't have glass holding them in, or pumps supplying air.

    It's true that if many of the things about out planet which permit life as we know it, changed, that life as we know it would be devastated. However life is pretty hardy, and there might be a mass extinction, but I would be willing to bet that given enough time life would bounce back from it, adapt to the new conditions and go on living.


    Also as dr.spo said, the probability of life existing else ware in the universe is almost laughably in favor.

    Think about it, there are millions (billions?) of galaxies that we know about. Those galaxies have millions (billions?) of stars. Even if it's rare for planets to exist around stars, which I believe they are finding it to be quite common, that's still millions (billions?) of planets.

    The idea that life exists only on Earth, is insane.
    Always minimize the variables.

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  5. #4 Re: Earth and conditions for life 
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    Quote Originally Posted by termina
    Hello!



    Many properties of our planets are claimed to be fine-tuned in the exact proportions to permit life emergence and its evolution:


    Earth's axial Inclination of 23°

    Moon stabilizing Earth's axis.

    Solar-system's perfect position in the Milky way.

    The presence of nearby galaxies

    so on...

    But, in spite of their important quantities, are these features really improbable to occur together in any planet of Universe except the Earth?
    Many of us probably wonder about life in the universe, but not having any real off world experience it's hard to say for sure what's really going on out there. But if I had to hazard a guess, I'd say it exist within the laws of nature anywhere that it can. I think life in general is probably fairly common, but life capable of becoming technical such as humans have on planet Earth is on the rare side. Rarer even still might be a life form that becomes capable of interstellar travel. Whether we can become that capable remains to be seen. I'd like to think we will have the time to make it so, but I have a very big doubt that we will.
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  6. #5 Re: Earth and conditions for life 
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    Quote Originally Posted by termina
    Many properties of our planets are claimed to be fine-tuned in the exact proportions to permit life emergence and its evolution:
    I would strongly challenge the highlighted phrase. In extensive reading of works on the origin of life from both perspectives (it is very common: it is very rare) I have never encountered that prhase, implicitly or explictly. Yes, it appears that there are many aspects of our planetary environment and character that are conducive to life, but most of these could have varied by quite a lot and life would still have arisen and evolved.
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  7. #6  
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    Hello termina!
    “But, in spite of their important quantities, are these features really improbable to occur together in any planet of Universe except the Earth?”

    No one knows what the total number of factors are or how likely each one is to occur anywhere else. If there are a googol planets in the universe, but the odds for life evolving turn out to be one in two googol, then there is no life elsewhere. There is not a predictive discipline of science that can tell us what the odds are since we cannot exactly describe how life began here. So belief and conjecture masquerade as fact and science. I prefer to base my sanity on knowledge and not popular opinion. :wink:
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  8. #7  
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    Ahem...

    You have to ask yourself: If things here are so damn perfect for life, why did it evolve only once? So far, it seems that all life had a common ancestor. That suggests that life here is all there is... in the entire cosmos, apart from that which originated here or in the comet that seeded us, (if it did).

    It's possible that other life did evolve however, I suppose, with different dna, we can't know all organisms that have ever lived.
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  9. #8  
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    Quote Originally Posted by human1
    Ahem...

    You have to ask yourself: If things here are so damn perfect for life, why did it evolve only once? So far, it seems that all life had a common ancestor. That suggests that life here is all there is... in the entire cosmos, apart from that which originated here or in the comet that seeded us, (if it did).

    It's possible that other life did evolve however, I suppose, with different dna, we can't know all organisms that have ever lived.
    Not sure what your point is, but on this world the winners do all history writing. In the evolutionary arena survivors are the winners and I suppose that could extend all the way back to the very first building blocks of life coming together in the primordial soup and what's happening in the rest of the universe will just have to wait until we have more data.
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  10. #9  
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    [quote="Lance Wenban"]
    Quote Originally Posted by human1
    Ahem...
    Not sure what your point is, but on this world the winners do all history writing..
    That's only really true when the loser is completely annihilated or in the past when they didn't have a written language.
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  11. #10  
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    [quote="Lynx_Fox"]
    Quote Originally Posted by Lance Wenban
    Quote Originally Posted by human1
    Ahem...
    Not sure what your point is, but on this world the winners do all history writing..
    That's only really true when the loser is completely annihilated or in the past when they didn't have a written language.
    Sorry but you missed my point altogether. There's more to writing history than the written language. History is also written by the fossils that have been left for us to find. Now I'm not saying there was any competition in the building of the original DNA, but if there was, what ever it was did not last long enough to leave any fossils for us to find and in that sense did not write any history. In other words they were losers.

    Maybe DNA could have developed differently than it did, I really don't know, and neither does anybody else. So until the first off world DNA is discovered it will remain one of those unanswered questions.
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    LOL. Np Got my thread mixed up anyhow.

    As for the thread. It's quite possible the current DNA system was built off the scaffolding of a simpler system. Meaning it's not so much the early system lost per say, but was more subsumed and eventually replaced.

    -
    I've read and heard that the Earth is perfect, but usually attached to arguments that god must have set things that way for humans and whatnot. Meanwhile we've come to recognize amazingly destructive events in the past that drove large numbers of species into extinction. In the far future we might find there are planets which are actually far more favorable to life than the rock we live on--we just know yet either way.
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  13. #12  
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    Quote Originally Posted by Lynx_Fox
    LOL. Np Got my thread mixed up anyhow.

    As for the thread. It's quite possible the current DNA system was built off the scaffolding of a simpler system. Meaning it's not so much the early system lost per say, but was more subsumed and eventually replaced.

    -
    I've read and heard that the Earth is perfect, but usually attached to arguments that god must have set things that way for humans and whatnot. Meanwhile we've come to recognize amazingly destructive events in the past that drove large numbers of species into extinction. In the far future we might find there are planets which are actually far more favorable to life than the rock we live on--we just know yet either way.
    I don't know how perfect it is. When the climate heats up a couple more degrees and the oceans rise say another 30 feet. What do you think is going to happen to the existing human population? Does the phrase “it's not looking good” sound a bit tame? Over a billion people now live close enough to the coast to get flooded. They will have to relocate and that's a conservative estimate. I can guarantee that those living on their new beach front property aren't going to be happy with millions of new neighbors on short notice. Also what about the new desert land and the much worse storms, not to mention this is all happening when our oil reserves are winding down. But then what do I care, I won't be around to see it.

    Next question. What about the advancement of the human race? I can pretty much guess that most of the population will be to pre-occupied with survival to be worried about landing on the moon. By the time the Earth cycles through it's greenhouse phase the total human population could very well be less than 2 billion. How well do you think they are going to do through the next ice age phase? I can be fairly certain we won't be deflecting any asteroids coming our way and if any humans are left when the Earth stabilizes into a new stretch of mild climate again, we won't have the same resources we have now to work with, because we are using them up right now.

    I'm going to go out on a limb and say I don't think we have much of a chance to establish viable off world colonies before the shit hits the fan. I know there are many of you that will think me a pessimist, but I prefer thinking of myself more as a realist.
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  14. #13  
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    I think that real progress with robotics, carbon fiber and space exploration will allow the entire population of the Earth to live in near Earth orbit within a century or two.
    http://wiki.spaceelevator.com/
    http://en.wikipedia.org/wiki/Asteroid_mining
    http://www.nss.org/settlement/space/bernalsphere.htm
    http://en.wikipedia.org/wiki/Dyson_Sphere
    Unlimited growth would then follow. Anything that can be organized can be done.
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  15. #14  
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    Quote Originally Posted by Arch2008
    I think that real progress with robotics, carbon fiber and space exploration will allow the entire population of the Earth to live in near Earth orbit within a century or two.
    http://wiki.spaceelevator.com/
    http://en.wikipedia.org/wiki/Asteroid_mining
    http://www.nss.org/settlement/space/bernalsphere.htm
    http://en.wikipedia.org/wiki/Dyson_Sphere
    Unlimited growth would then follow. Anything that can be organized can be done.
    A century or two. If I thought we had a century or two left to get that kind of stuff done I might agree with you. However I think the human race will be to busy with other distractions long before it can establish a viable off world presence. I did say viable, which means able to take care of itself without any help from Earth.
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    This is off topic but...
    Dyson figured that about a quarter of the population of a Bernal sphere would work at building more spheres. Growing exponentially, enough living space would be built in less than 60 years for the entire population of the Earth. This wasn't even considering the effect of robotics. Each Bernal Sphere is self-sufficient. If there is a legitimate need, such as a global catastrophe, then this would be done in record time. Most of the technology already exists.
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  17. #16  
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    Quote Originally Posted by Arch2008
    This is off topic but...
    Dyson figured that about a quarter of the population of a Bernal sphere would work at building more spheres. Growing exponentially, enough living space would be built in less than 60 years for the entire population of the Earth. This wasn't even considering the effect of robotics. Each Bernal Sphere is self-sufficient. If there is a legitimate need, such as a global catastrophe, then this would be done in record time. Most of the technology already exists.
    You definitely meet the requirements of being an optimist, but I remain unconvinced. The human race is a great deal more fragile than you imagine.

    If the whole world could pull together under one world government and work towards fixing our problems, we might have a chance. Oops! Like that's ever going to happen?
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  18. #17 Rare Earth 
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    There are 2 considerations here

    1. The environment [ ie the Earth ] and how complex life got started
    2. How sentient life emerges from the complex life forms

    I find that the easiet way to try and answer these issues is to employ the technique referred to in Stephen Hawkings recent book - model dependant realism. In the context of the second consideration above, MDR allows us to eliminate a great many species that just don't fit the model - invertibrates, egg layers, marine animals etc.

    If you start from this standpoint, and formulate a model of whatever is under consideration, you can then start looking at the various options and ask the question 'does this fit the model?' if it doesn't - you can discard it.
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  19. #18 Re: Rare Earth 
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    Quote Originally Posted by tszy
    There are 2 considerations here

    1. The environment [ ie the Earth ] and how complex life got started
    2. How sentient life emerges from the complex life forms

    I find that the easiet way to try and answer these issues is to employ the technique referred to in Stephen Hawkings recent book - model dependant realism. In the context of the second consideration above, MDR allows us to eliminate a great many species that just don't fit the model - invertibrates, egg layers, marine animals etc.

    If you start from this standpoint, and formulate a model of whatever is under consideration, you can then start looking at the various options and ask the question 'does this fit the model?' if it doesn't - you can discard it.
    It sounds like you are equating sentient life and technological life as the same thing. Both porpoises and octopuses are very intelligent life forms. The porpoise has no arms with hands and can't build anything no matter how smart and sentient they might be and the octopus has such a short life it doesn't have enough time to do anything but breed and die. I really don't know enough to say they are not sentient and I'm not convinced that anybody else does either.
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    A most absorbing topic.

    The sheer number of galaxies and therefore Earth like planets does hold a tantalizing possibility that statistically life should occur on some other planets.
    I have no doubt that this is the case. The building blocks of life are all over the cosmos - water, organics etc. As to the emergence of an intelligent technological species, this is far less certain

    Having read the 'Rare Earth' hypothesis, it does make some important points about where and when life can occur. There are habitable regions and eras of the
    cosmos as a whole, within galaxies and within solar systems. When these limitations are applied to the Drake equation, the result is vastly reduced.

    One of the most significant events on the Earth for the evolution of homo sapiens
    was the ateroid impact [ and possible additional volcanic activity ] that cleared the way for small mammals to develop and evolve - especially into the tree dwelling anscestors of the primates. Presumably if this event had not happened or had been much less severe, the Earth would still be dominated by large reptilian species and I could not be sitting here typing.

    When you consider the sheer number of completely chance occurrances that led to the appearance of life on this planet and ultimately us.
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  21. #20 Re: Rare Earth 
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    Quote Originally Posted by Lance Wenban
    Quote Originally Posted by tszy
    There are 2 considerations here

    1. The environment [ ie the Earth ] and how complex life got started
    2. How sentient life emerges from the complex life forms

    I find that the easiet way to try and answer these issues is to employ the technique referred to in Stephen Hawkings recent book - model dependant realism. In the context of the second consideration above, MDR allows us to eliminate a great many species that just don't fit the model - invertibrates, egg layers, marine animals etc.

    If you start from this standpoint, and formulate a model of whatever is under consideration, you can then start looking at the various options and ask the question 'does this fit the model?' if it doesn't - you can discard it.
    It sounds like you are equating sentient life and technological life as the same thing. Both porpoises and octopuses are very intelligent life forms. The porpoise has no arms with hands and can't build anything no matter how smart and sentient they might be and the octopus has such a short life it doesn't have enough time to do anything but breed and die. I really don't know enough to say they are not sentient and I'm not convinced that anybody else does either.
    It sounds like I'm equating sentient life and technological life as the same thing - guilty as charged. We tend to look at other animals with a bias that makes us map human qualities and behaviour on their actions.

    I accept that an octpus can exhibit what we interpret as intelligence but It's a bit like UFO chasers, people see what they want to see. I don't see any evidence of an Octopus culture [or their space program.]

    I agree 100% with your point about the porpoise. This actually enforces my argument. If you apply Stephen Hawkings MDR methodology, the porpoise does make it through several cuts being a mammal etc but is ultimately eliminated because they do not fit the model.

    You seem to wish to apply species with some kind of embryonic intelligence and therefore the potential to evolve into something like us. It is clear however that we are not the end goal of evoulution and this presents the real possibility that we are unique. Although we may certainly find archaea and bacteria all over the universe, complex life forms will be much rarer.

    And as for something like us, well at the moment there is a sampe of one - clearly not a tendancy.
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    @ tszy

    You seem to wish to apply species with some kind of embryonic intelligence and therefore the potential to evolve into something like us. It is clear however that we are not the end goal of evolution and this presents the real possibility that we are unique. Although we may certainly find archaea and bacteria all over the universe, complex life forms will be much rarer.

    And as for something like us, well at the moment there is a sample of one - clearly not a tendency.

    I have a theory that intelligence itself has an evolutionary path of it's own outside of biological life. If so, we humans are in a position to be considered first stage as we are in a unique position to create or transform into second stage or machine intelligence. Probably a very controversial idea.
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    The trouble is that you cannot extrapolate from a sample of one. We just cannot determine the probability of the many events and conditions that led to human life evolving on Earth until we statistically examine those conditions on other sample planets.

    Until we can do this it is impossible to determine whether life is unique to Earth, or common throughout the Universe.
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  24. #23  
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    Quote Originally Posted by muppet
    The trouble is that you cannot extrapolate from a sample of one. We just cannot determine the probability of the many events and conditions that led to human life evolving on Earth until we statistically examine those conditions on other sample planets.

    Until we can do this it is impossible to determine whether life is unique to Earth, or common throughout the Universe.
    You are right in one sense. We don't have absolute proof of life anywhere but on Earth. But we do have many examples of how nature works and the probability that Earth is the only place in the universe where the conditions for life became a reality is so small as to not even be an issue.

    While proof is still very important, it seems to be a very good bet that life exist elsewhere in the universe. What doesn't seem to be a good bet is that we will ever meet other intelligent beings before we go extinct or just lose our technology do to some disaster like climate change or one of the many other scenarios we've all seen on TV.
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    Quote Originally Posted by Lance Wenban
    We don't have absolute proof of life anywhere but on Earth. But we do have many examples of how nature works and the probability that Earth is the only place in the universe where the conditions for life became a reality is so small as to not even be an issue.
    This is a common argument made by those interested in abiogenesis, but is one that I have long felt is flawed - fatally so. It is, in essence, a circular argument. Since life arose on the Earth quite rapidly after its formation then it must be easy for life to arise, therefore it will arise quite easily on other planets where similar conditions are present.

    However, if we were the only planet in the entire universe on which life of any kind had arisen we would be making the same observation: Since life arose on the Earth quite rapidly after its formation then it must be easy for life to arise,

    As muppet said, extrapolating from a sample size of one is a chancy business.

    There are three ways in which we could resolve this uncertainty. The first two involve having a larger sample size.

    1. If we find life elsewhere (Titan, Mars, Area 51, it doesn't matter) then the probability of life can be assessed quantitatively rather than qualitatively. (Anyone who thinks the current Drake equation yields quantitiative results has missed the point.)
    2. Even better than life on Mars would be life on Earth that did not share a common ancestor with us.
    3. Define in detail a series of plausible reactions under known constraints that lead to the emergence of life from prebiotic chemistry and duplicate these reactions in a laboratory.

    Until we have done one of these things then the possibility that we are the only life in the entire universe remains a viable possibility and very much an issue.
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    @ Ophiolite

    One thing we do have absolute proof of is that life in this universe does exist. The idea that it is so rare as to only exist on Earth seems totally without merit.

    Having said that and believing that, I think proof would be very good indeed.
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    Quote Originally Posted by Lance Wenban
    The idea that it is so rare as to only exist on Earth seems totally without merit.
    You are making an assertion with no foundation. You offer no substantitve evidence to support that assertion. That is not science, that is rhetoric. The lack of merit here is in your argument.
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    Quote Originally Posted by Ophiolite
    Quote Originally Posted by Lance Wenban
    The idea that it is so rare as to only exist on Earth seems totally without merit.
    You are making an assertion with no foundation. You offer no substantitve evidence to support that assertion. That is not science, that is rhetoric. The lack of merit here is in your argument.
    Statistics is science anyway you look at it, and makes a very good foundation.
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    Statistics is not science, it is a tool of science.
    A sample of one is not a foundation for a statistical analysis.
    You continue to make assertions. This is unscientific.
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    Quote Originally Posted by Ophiolite
    Statistics is not science, it is a tool of science.
    A sample of one is not a foundation for a statistical analysis.
    You continue to make assertions. This is unscientific.
    Whatever then, science uses probabilities, odds or statistics. You can call what I said an assertion if you like, but I did say a couple of times that we didn't have proof to keep everything I was saying in the correct context, so I am not understanding your problem. Talking about probabilities of something within the correct context is not unscientific. Real scientists do it all the time.

    You can call Earth a sample of one if you want, but the universe itself is not a sample of one and saying there is a probability of life out there somewhere other than on Earth is reasonable.
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    Quote Originally Posted by Lance Wenban
    You can call Earth a sample of one if you want,
    I am calling the Earth a sample of one not because I want to, but because that is exactly what it is. At present the evidence strongly suggests - so strongly that only a few mavericks suggest that there may even be an alternative - that all life on Earth is descended from a single common ancestor. If this is so - and 99.95 of biologists agree - then the Earth's biosphere is a sample of one.

    Quote Originally Posted by Lance Wenban
    ........ but the universe itself is not a sample of one
    Until and unless we find life elsewhere the universe is most assuredly a sample of one. Within the universe there is only one known example of life - the Earth's biosphere. That makes the universe, currently, a sample of one.

    Quote Originally Posted by Lance Wenban
    ........ saying there is a probability of life out there somewhere other than on Earth is reasonable.
    That is entirely reasonable. i.e. there is some probablility that life exists elsewhere. That probability may be vanishingly small, or it may be unity. With our current knowledge, and having access to only a sample of one, we cannot quantify this probability. Yet you effectively and implicitly did so when you stated:

    The idea that it is so rare as to only exist on Earth seems totally without merit.
    That statement implies the probability of life elsewhere is unity. Yet there is no evidence, from our single sample, to support that contention. It remains an unfounded assertion. I happen to agree with you, but my agreement is no more than opinion. It has no scientific merit whatsoever - just as your assertion has no scientific merit.
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    Quote Originally Posted by Ophiolite
    Quote Originally Posted by Lance Wenban
    The idea that it is so rare as to only exist on Earth seems totally without merit.
    That statement implies the probability of life elsewhere is unity. Yet there is no evidence, from our single sample, to support that contention. It remains an unfounded assertion. I happen to agree with you, but my agreement is no more than opinion. It has no scientific merit whatsoever - just as your assertion has no scientific merit.

    Okay if you agree with me, your problem is with my choice of words. In the example above, I said 'seems totally without merit' and not 'it is totally without merit'. I thought that difference was sufficient. I will try to do better in the future. However from what you said, you did get the communication as I intended it to be.
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    Quote Originally Posted by Lance Wenban
    Okay if you agree with me, your problem is with my choice of words.
    Lance, you are still not getting it. I agree that I supect there is probably life on other planets, but this is not a scientific position, it is an expression of an opinion. Equally your assertion that the probability of there being no life on other planets seems to be an idea without merit, is very decidedly an opinion.

    Try it this way: it is not a viable scientific position, based on current evidence, to rule out any consideration of the possibility that life on Earth may be the only life in the universe. However, that is exactly what you did. That is what I was objecting to.

    I hope that is now sufficiently clear, or boring that we can end it now.
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  34. #33  
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    Ophiolite Discoveries only this year have found the universe to be a lot bigger than we thought, with trillions of trillions of stars. Some several hundred planets have been discovered so far and NASA says there are upto 30 billion Earth-like planets in our galaxy alone

    http://astrobiology.arc.nasa.gov/new...ws.cfm?id=1227

    We have discovered the ingredients for life beyond our solar system, long chain tholins and the like, as well as water (including a water world).

    Then again, why look that far? Mars releases huge amounts of methane every Martian summer and the only way this can be accounted for is bacteria under the surface. Mars also has water on it, as in two photos taken a few years apart showed the after affects of water movement. Reactions recently detected on Titan are best explained by methane based life existing there. Of course there is not the slightest evidence at present that there is any life in the water below Europa's surface but no one would be surprised if there was.

    Better telescopes mean that in the next decade or two we will not only find the pollution caused by life in the atmosphere of exoplanets but even real pollution from industry may be found. No serious astronomer will now say that life does not exist anywhere else in the universe. Even the vatican observatory has gotten in on the act.
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  35. #34  
    Universal Mind John Galt's Avatar
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    Quote Originally Posted by Cyberia
    Ophiolite Discoveries only this year have found the universe to be a lot bigger than we thought, with trillions of trillions of stars. .
    Which is wholly irrelevant to my central point. The universe can be infinite and we are still dealing with only a single sample of known life. Conclusions based on that probability are invalid if they lead to statements such as those made by Lance.
    Quote Originally Posted by Cyberia
    Some several hundred planets have been discovered so far and NASA says there are upto 30 billion Earth-like planets in our galaxy alone
    Google my forum name and exoplanets and you will likely turn up posts of mine saying exactly this. It makes no difference to the fundamental point.
    Quote Originally Posted by Cyberia
    We have discovered the ingredients for life beyond our solar system, long chain tholins and the like, as well as water (including a water world).
    We have detected well over 100 organic compounds in GMCs. Since we have not determined the steps and conditions for these steps, to move from pre-biotic chemistry to life, we cannot make any meaningful quantitative conclusion as to probability.
    Quote Originally Posted by Cyberia
    Then again, why look that far? Mars releases huge amounts of methane every Martian summer and the only way this can be accounted for is bacteria under the surface.
    No. This is not the only explanation. (And I speak as one who strongly suspects Gil Levin's labelled release experiment on the Viking landers detected life.) And until we have confirmed the existence of Martian life and established that it is not genetically related to Earth life, then quantitative estimates of the probability of life in the rest of the universe remain speculative.
    Quote Originally Posted by Cyberia
    No serious astronomer will now say that life does not exist anywhere else in the universe.
    Any astronomer who makes such a statement needs to take a course in biology and another in statistics, or stay out of a field in which he clearly is ignorant.

    And as final remark on Earth like planets: we do not know which aspects of the Earth were necessary for the origin of life, therefore we do not know how many planets capable of generating life there may be.

    Seasons greetings.
    O.
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  36. #35  
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    Cyberia,
    Methane on Mars is not necessarily a product of bacterias.

    As it is written in this article
    http://www.nasa.gov/mission_pages/ma...rsmethane.html,
    also geological processes might cause its presence.
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  37. #36  
    Universal Mind John Galt's Avatar
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    Indeed the very presence of seasonal methane is being questioned, with the possibility raised that it is an aritfact of the sensing process.See the report in the 8th January issue of New Scientist (p 11), or the original paper in November issue of Icarus.
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  38. #37  
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    L o c a t i o n , L o c a t i o n , L o c a t i o n

    Given that there is life on Earth,
    Our solar system had to be
    In the outer-more portion of the galaxy,
    For, if not, we could have never been;
    And, in fact, it is on a spiral arm.

    Reality’s building blocks are quite ancient,
    But have been reshuffled by galactic cores.

    All galaxies are vortexes similar to ours,
    Very little material within appearing
    Older than the galactic transit time.
    This is why the entire universe
    Appears to have a finite age,
    And why our local neighborhood
    Appears to be about 10 billion years old.

    Even globular clusters seem
    Older than the galaxy they orbit,
    For their trajectories lie outside
    The galactic vortex,
    And so they are not pulled into
    The recycling engine
    With the same regularity
    As its disk material.

    It took about 10 billion years
    For our solar system to reach
    Its current distance from the galactic rim.
    How long until it falls into the core?

    The time it takes to fall through
    The luminous portion of our galaxy’s disk
    Is about 16 million years,
    Which is called the galactic transit time.

    Any star born on the Milky Way’s rim
    With a mass smaller than that of our sun
    Will still be burning when it
    Falls into our galaxy’s core.

    Indeed, our own sun has enough fuel
    To burn for another 4-5 billion years.

    At its current rate of descent,
    Our solar system will be in
    The Milky Way’s core region
    In less than 4 billion years,
    To be consumed by the voracious beast
    Of the galaxy’s Black Hole,
    Perhaps, while it is still burning
    So mark your calendars.


    — The Infernal Regions —

    Hellholes hurl thousand light-year jets of fear,
    In Centaurus, cross’d the galactic sphere,
    Supermassive darkling beasts devour all…
    Abandon hope, all ye who enter here.


    There are two unforgiving time constraints
    For the evolution and long term survival
    Of life in the universe.

    It must advance from bacteria
    To full scale space transport
    Before its sun fails
    Or falls into the core of the galaxy,
    Whatever comes first.

    Earth has already had a total run
    Of about 4.5 billion years
    Since our sun’s ignition.

    If Sol had started burning
    Any closer than about
    25 thousand light years
    From the Milky Way’s core,
    Our civilization simply would not exist.

    All this we could have expected,
    For we are here.
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  39. #38  
    Universal Mind John Galt's Avatar
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    As far as I read, which isn't far, most of what you posted was nonsense. Please stop desecrating threads with your peculiar brand of lunacy.

    Thank you.

    (If you wish to refute my accusations, simply provided citations to relevant research articles published in peer reviewed journals. Thank you again.)
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  40. #39  
    Moderator Moderator Dishmaster's Avatar
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    Quote Originally Posted by questor
    At its current rate of descent,
    Our solar system will be in
    The Milky Way’s core region
    In less than 4 billion years,
    To be consumed by the voracious beast
    Of the galaxy’s Black Hole,
    Perhaps, while it is still burning
    So mark your calendars.
    Bogus! There is no evidence for such an inward movement whatsoever. Where did you get this from? I suggest, you read up the term "differential rotation" in the context of our Milky Way.

    Please note that this is a science forum, not a science fiction forum.
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