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  1. #1 terraforming 
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    i'm unaware if this has previously been debated so please forgive my ignorance. however something important came to mind after reviewing a post made on the forum about how we try to save species.

    We often introduce organisms into an environment that change that environment in such a way that some of the previous species are no longer fit to survive. seeing the "negative" (to me this is subjective but i realize to many it is not) effects of our actions we try to save the species no longer fit to survive.

    My big question however, is why we're opposed to introducing species to environments where their effects could be greatly benificial. is it ethics that stops us? do we not want to upset the "natural order" of things? all this seems very stoic to me in an age where our studies of ecology, genetics, microbiology, and all other fields of biology has led us to a scientific understanding of biology as a chemical system that we've never before had.

    rather than glorifying the current chemical systems as "the natural order" shouldn't we do what we can to affect them in a way that can help increase the standard of human living?


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    We lack sufficient understanding of systems - any systems - to be able to 'interfere' with them without standing a substantial risk that something unexpected and probably negative will happen.


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    what could go wrong on mars? or the moon? or any planet besides our own? nasa takes rediculous measures to prevent any micro-organisms from leaving earth or returning to earth on its shuttles. the only life-forms we take up are humans and a few bacteria on our skin(i believe they try their best to kill those before we leave too).

    so, what's the possible harm of terraforming mars? it has the neccisary elements for life. engineered bacteria could extract the materials from the rocks and produce even more carbon dioxide. the carbon dioxide should pile up to the point where the greenhouse effect keeps mars fairly warm.

    obviously humans can't naturally live on mars but by producing such high carbon dioxide levels and adding some photosynthetic organisms, we can make mars a green planet just like earth.
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    Bone loss could be a serious problem to long-term human residents on Mars.
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    Quote Originally Posted by saul
    what could go wrong on mars? or the moon? or any planet besides our own?
    I didn't say there was, because that's not the question you asked. You clearly asked about introducing life forms from one terrestrial environment to another. I gave you my view on that.

    The great care being taken to sterilise probes that contact other planets is to minimise the risk of contaminating them so that we later think we have discovered life on another planet. Sensible, don't you think?

    If you want an understanding of the arguments against terraforming Mars then read the Mars trilogy by Kim Stanley Robinson.
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    my apologies if i had made it seem as if i were only talking about terraforming the earth. i was talking about any environment.

    and i agree that when we're trying to find life somewhere we should sterilise our probes. however we've sent rovers to mars and we have pretty conclusive evidence there is no longer any life there, if there ever was. i will read the books you have suggested when next i have the chance, however to prevent this topic from becoming to stale, would you min presenting the more important arguements against it on this page?

    and free radical, i agree that for colonists on mars planning to return to earth, bone loss could be a significant hazard. i believe there are simple methods to make bone loss a non issue, the typical idea for long distance space flight is artificial gravity via spinning a disc that functions as the living area. a similar orbital craft could have the gravity adjusted over time to slowly build up bone strength for those coming back to earth. for mars colonists however, bone loss should be a non-issue, while on a planet with reduced gravity their bones would only decay to compensate for gravity, no more than that, they would only need to regain the mass if heading back to earth.
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    Bone loss is, of course, only one of the possible harmful long term consequences of living under reduced gravity.

    Having said that, I have to admit that no-one really knows at this stage what prolongued life under one third gravity would do to the human animal, assuming no return to Earth.

    Another problem is radiation. Without a strong magnetic field, Mars permits charged particles to enter, which are cancer causing.

    My own view is that any Mars colony will have to first live underground. This is to stop radiation, but also will provide suitable air tight habitats.

    Terraforming Mars would have to be a very long term venture. Thousands of years. The biggest problem I would see is providing warmth on a planet wide scale. It might be possible to use mirrors in orbit to reflect extra heat down. The problem is that those mirrors would have to be under constant care and control. Imagine if a war should break out on Mars, and stop those concerned with the mirrors from doing their job! Result : planet wide chilling, and deaths of a large part of the population.
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    ramping up the greenhouse gasses could keep the planet at reasonable temperatures. not tropical, but within colder earth temperatures. purpose-built lifeforms on mars could be engineered to thrive in the gasses that we find toxic.

    and if the atmosphere can be made to be as toxic to humans as we like, then having the initial bacteria produce ozone as well would lessen the burden of radiation on the surface of mars.

    biology has found ingenious solutions through natural selection on earth, there are bacteria growing on the inside of containers of nuclear waste. observing their adaptations and incorperating them in organisms we send to mars could make radiation a non-issue for lifeforms on mars.

    unfortunately i doubt ethics would permit creation of a human with engineered cells that are similarly resistant to radiation, but that's ethics for you.

    and skeptic, i agree completely that the terraforming of mars won't be complete for hundreds of years, but it is my conviction that it will begin before i am retired. perhaps the first colonists would be from my grand children's generation. unfortunately i don't think we'll get a practice run with terraforming on the moon, its gravity couldn't support any type of atmosphere, and i doubt an ecosystem could exist where nutrients must all be taken from the soil.
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    saul



    First : no amount of ozone will stop the radiation. We are talking of charged particles, not the ultra violet that ozone works on. Enough atmosphere might do the job, more or less, but it would take a lot.

    It would also take one hell of a lot of greenhouse gases to raise temperatures to anywhere near Earth. Maybe a pile of CFC's might do it. Billions of tonnes! However, the mirror system is probably more practical. Whatever is used, it will not happen for a long time, and I doubt that our knowledge of current technology would give us a clear idea of what is practical.

    A genetically engineered human?
    Currently not acceptable ethically, but I would not assume that to be the case in the distant future. In the 1960's it was considered unethical to use artificial insemination on humans. Today it is commonplace. Ethics change.
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    Life on Mars has certainly not been ruled out.

    http://www.universetoday.com/23675/l...ished-on-mars/

    http://www.universetoday.com/65823/n...-life-on-mars/

    It is not yet known whether the Martian gravity is sufficient to maintain human bones over the long term to a reparable degree, however the lowered gravity is unquestionably a challenge.

    http://en.wikipedia.org/wiki/Mars_Gravity_Biosatellite
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    admittedly there is a small possibility of life on mars still existing. wherever there is water and some form of energy there is a possibility. hopefully it is just geologic activity, if we could difinitively say that mars was barren then colonization would be without issue and hopefully humanity could set up a nice second home. however if it is biological, no terraforming would be allowed, researchers (if any stayed on the planet) would have to stay in the above described underground shelters to protect from radiation. the general value of mars would drop significantly. even though humanity has this idea that natural life outside earth would be a great discovery, our fascination with it would most likely get in the way of making good use of the resources provided for us by the planet this life is found on.

    additionally, i agree that the effects of 1/3 gravity on a human being for an indefinite timescale are not yet known, it could be that we would need some form of artificial gravity even if not returning to earth. if that's the case then making good use of the red planet would be very costly.

    but despite the chemical conditions on mars (as well as the condition of the climate) i'm confident that with biological engineering technology that's coming along in just the next decade we will be able to create lifeforms that would thrive on mars and generate systems on mars that behave in a predictable way.
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    Quote Originally Posted by saul
    i will read the books you have suggested when next i have the chance, .
    You should definitely do this since they contain detailed discussions not only of the ethics of terraforming but the methods of doing so. It is all reasonably hard science - certainly as hard as anything you get in SF.
    Quote Originally Posted by saul
    would you mind presenting the more important arguements against it on this page?
    The arguments are fivefold:
    Ethical - We do not have the intrinsic right to 'despoil' another environment.
    Restitution - We have half destroyed the environment on one planet. Until we have learned how to conduct ourselves properly we should not interfere with the rest of the universe.
    Aesthetic - The Martian environment is unique and wonderful. Its integrity should be respected.
    Knowledge - Most of Mars has remained unchanged for over three billion years. It will take generations to properly study it in an unaltered state. Terraforming should at least be delayed until then.
    Biological - Primitive life forms may exist somewhere on the planet. (Extremophiles were only recently recognised on Earth.) If we terraform we might destroy a complete alien biosphere.

    These are my interpretations of the arguments expressed both explicitly and implicitly by those who in the novel who are opposed to terraforming.
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    Re those arguments

    1. Ethical.
    Ethics are intrinsically variable. Every new generation has a new set of ethics. Who knows what the ethics will be when humans are in a position to consider terraforming Mars.

    2. Restitution. This ties in with the 5th statement - biological. Obviously, the first thing humans will do on Mars is study it rigorously. If there is no biological restraint, then terraforming is not an issue. Any geological treasures are unlikely to be significantly adversely affected by terraforming.

    3. Aesthetic. Like ethics, this is enormously variable. Who is to say that a barren red Mars is more aesthetic than a terraformed and green Mars.

    4. Knowledge. I do not think humans will be in a position to even begin terraforming for many generations. Ample time for knowledge gathering.

    Overall, assuming no indigenous Martian life forms, I see no reason for long term prevention of terraforming.
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    Just so we are clear, those are not my arguments, so I will not be responding to your counterpoints. I may have done a poor job of presenting the arguments, so your counterpoints - argued from conviction - may appear more persuasive than an objective comparison would allow. Perhaps someone holding a Mars First viewpoint will join in and offer a more spirited defence.
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    i'd rather not go into the ethics and aesthetics of it all, we've already had the oppurtunity to discuss this on the topic i posted (i believe under philosophy) as "galactic expansion, do we have the right?" it dealed with the ethics and other factors behind human expansion and although i was argueing against expansion untill we got it right on earth, the arguements against me were quite clear and both positions have an equally strong base.

    however as far as the knowledge to terraform mars, i disagree with you greatly, within a decade or two i expect we will have already created microbes that could survive on mars and do the job of terraforming the planet.

    i agree completely that our first course of action should be to find out if there is life on mars. but within two or three decades it is not likely that we will have left that question unanswered.

    and finally, skeptic i say this respectfully: you're quite incorrect about the geologic treasures. since life has evolved, it has played an enourmous role in shaping our abiotic environment(geologic factors included) and the terraforming of mars would greatly alter the atmosphere, hopefully increase the amount of water so that it has rivers again, and completely transform the surface of the planet.

    perhaps for the first generation the old geology would still be viable for studies, but after that terraforming will have already completely changed the surface of mars, the only thing left of the old mars will be beneath the surface.
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    As for the ethics, I think unless we find some incredible treasure trove of an ecosystem under the surface which has escaped notice so far we'll eventually colonize and adapt the planet to suit our needs.

    I think the radiation risk is not the most dangerous aspect by a long shot and largely overemphasized by the media and pop science. It might be a good idea to live, or at least sleep, largely underground anyhow for other reasons.

    Changes to the planet can start pretty modest anyhow. We don't need it as warm as earth for example, we just need the equatorial summers to get above freezing. We don't need a breathable atmosphere, we just need an atmosphere thick enough so we could get by outside with light clothing and a reliable source of oxygen etc. Do we really need running water? Or just enough water to conduct drip irrigation?

    I don't think any of us will see the start of this in our lifetimes. I hope I'm wrong. And none of us know what technological possibilities will exist a couple centuries for now.

    Given the opportunity-I'd go their tomorrow, regardless of the risk.
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    Quote Originally Posted by Lynx_Fox
    Given the opportunity-I'd go their tomorrow, regardless of the risk.
    Carry your bag sir?
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    Quote Originally Posted by Lynx_Fox
    As for the ethics, I think unless we find some incredible treasure trove of an ecosystem under the surface which has escaped notice so far we'll eventually colonize and adapt the planet to suit our needs.

    I think the radiation risk is not the most dangerous aspect by a long shot and largely overemphasized by the media and pop science. It might be a good idea to live, or at least sleep, largely underground anyhow for other reasons.

    Changes to the planet can start pretty modest anyhow. We don't need it as warm as earth for example, we just need the equatorial summers to get above freezing. We don't need a breathable atmosphere, we just need an atmosphere thick enough so we could get by outside with light clothing and a reliable source of oxygen etc. Do we really need running water? Or just enough water to conduct drip irrigation?

    I don't think any of us will see the start of this in our lifetimes. I hope I'm wrong. And none of us know what technological possibilities will exist a couple centuries for now.

    Given the opportunity-I'd go their tomorrow, regardless of the risk.
    i agree almost completely with you. completely transforming mars to resemble earth will take a long time and will be very difficult. it is much more logical to change it just enough that we can get by without bulky space-suits like we currently use. as long as the pressure is similar to earth at sea level and the atmosphere isn't corrosive to our skin, we could get by with as little as a breathing mask. that is the mars i envision us creating before i die, and start in as little as two decades.

    simple changes such as warming it to just above freezing, creating an atmosphere that biologically engineered organisms can thrive in, and reducing radiation enough for cancer rates not to be too high to colonists. obviously these simple changes would be difficult by current standards, but life's ability to change the environment has been demonstrated many times here on earth.

    however if any type of life whatsoever exists on mars then it will deffinately have to be studied extensively, the scientific community would not allow extensive terraforming of mars without first studying the ecosystem in place, and perhaps (although hopefully i'm wrong here) even then it would not be allowed for years.
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    Quote Originally Posted by saul
    however as far as the knowledge to terraform mars, i disagree with you greatly, within a decade or two i expect we will have already created microbes that could survive on mars and do the job of terraforming the planet.
    Probably not. There are two major obstacles:
    1. Lack of nitrogen and not enough hydrogen.
    2. Lack of magnetic field to shield the atmosphere from being blown away by solar wind. Without it, any imported hydrogen would be lost again.
    Neither problem can be solved by microbes.
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    Quote Originally Posted by Twit of wit
    Quote Originally Posted by saul
    however as far as the knowledge to terraform mars, i disagree with you greatly, within a decade or two i expect we will have already created microbes that could survive on mars and do the job of terraforming the planet.
    Probably not. There are two major obstacles:
    1. Lack of nitrogen and not enough hydrogen.
    2. Lack of magnetic field to shield the atmosphere from being blown away by solar wind. Without it, any imported hydrogen would be lost again.
    Neither problem can be solved by microbes.
    both nitrogen and montmorillonite are present in martian soil. montmorillonite is composed of heavy metals as well as hydroxides and water. so, the chemicals are not an issue.

    the atmosphere may not be able to be built up, but hydrogen doesn't have to be imported, there's is plenty already there. the atmosphere is comprised of over 95% carbon dioxide which isn't a particularly light gas, however microbial lifeforms could produce organic gases much heavier than this to greatly increase the pressure on the surface of mars.

    whether or not that would be enough to make mars an environment in which humans could easily live is unknown to me, however if that's not enough then longer term terraforming could be done by importing comets and asteroids to the surface of mars, but that would be hundreds of years from now, we've got the technology but not the will to do something like this.
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    It has been suggested that crash landing a few comets onto Mars might be the way to start the process. That would add heat energy to the surface of Mars along with a lot more water. The only problem there is that I would imagine human habitation would be well under way before anyone gets around to sending comets Mars way.

    The easiest way to terraform Mars is simply to build lots and lots of tunnels to live in. The environment within the tunnels can be warm, with water and oxygen.

    To terraform Mars in its entirety would be immensely difficult and require a very long period of time. Hundreds, if not thousands of years. Microbes can only do so much.

    And to Lynx Fox I have to say - do not underestimate the radiation problem. Humans cannot live unprotected for terribly long under that level of radiation. After about 3 years, you would be dying of cancer.
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    Quote Originally Posted by saul
    as long as the pressure is similar to earth at sea level and the atmosphere isn't corrosive to our skin, we could get by with as little as a breathing mask. that is the mars i envision us creating before i die, and start in as little as two decades.
    I think we could actually do that with less than 25% atmosphere, perhaps less.

    And to Lynx Fox I have to say - do not underestimate the radiation problem. Humans cannot live unprotected for terribly long under that level of radiation. After about 3 years, you would be dying of cancer.
    The last NASA estimate was something like +4% risk of cancer for a three year mission.
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    Risk of cancer is additive and exponential. It increases rapidly for every extra year of exposure.

    The solution is simple. 10 metres of soil and rock will stop the radiation. Thus, living underground makes you safe. The odd expedition above ground will not be as serious, if most of your time, you are underground.

    Yes, you can survive a 3 year expedition. However, we are talking of a colony, where people are born, spend many decades of life and experience the hard radiation throughout. Quite a different thing.
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    Quote Originally Posted by saul

    both nitrogen and montmorillonite are present in martian soil.
    Source?

    And to Lynx Fox I have to say - do not underestimate the radiation problem. Humans cannot live unprotected for terribly long under that level of radiation. After about 3 years, you would be dying of cancer.
    According to this the dose would be about 100 REM, that is 1000 mSv per year.
    This claims even less, only 100-200mSv
    While high, it's not too extreme. The highest natural radiation levels here on Earth are over 250mSv per year and even such levels are not harmful to people living there.
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    To Twit

    I admit that my wording was careless. I should have said that 3 years on Mars would increase the probability of cancer - not cause it. Consider me spanked.

    I have to say something about your reference though. It says that people living at high altitudes do not suffer health wise, as far as anyone can tell. That is true. In fact, high altitude dwellers on average live longer than those who live on the plains. But that has almost certainly got nothing to do with radiation. It may have a lot to do with stimulating greater lung development, and to breathing cleaner air. Perhaps even to the greater exercise of having to walk up and down hills.
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    Quote Originally Posted by skeptic
    Risk of cancer is additive and exponential. It increases rapidly for every extra year of exposure.
    Exponential? Can you provide a source for that? The most commonly used model is the linear no-threshold model by which the risk is assumed to be in proportion to accumulated dose. Even that is disputed because the radiation risk is low enough at chronic low doses as to be difficult to distinguish from other risk factors.
    http://en.wikipedia.org/wiki/Linear_no-threshold_model
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    Quote Originally Posted by Twit of wit
    Quote Originally Posted by saul

    both nitrogen and montmorillonite are present in martian soil.
    Source?

    And to Lynx Fox I have to say - do not underestimate the radiation problem. Humans cannot live unprotected for terribly long under that level of radiation. After about 3 years, you would be dying of cancer.
    According to this the dose would be about 100 REM, that is 1000 mSv per year.
    This claims even less, only 100-200mSv
    While high, it's not too extreme. The highest natural radiation levels here on Earth are over 250mSv per year and even such levels are not harmful to people living there.
    http://www.sciencedirect.com/science...c53473a9f5f861

    the abstract contains information on both the existence of montmorillonite in the soil and its composition.

    http://journals.cambridge.org/action...ine&aid=191609

    we have not yet run the tests mentioned in the above article to test for nitrogen in the soil, however i've checked eight other sources from universities and research centers and all hypotheses by said groups agree that lack of nitrogen in mars' atmosphere is evidence that there are large amounts of nitrogen in the soil.
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    Quote Originally Posted by Twit of wit
    2. Lack of magnetic field to shield the atmosphere from being blown away by solar wind. Without it, any imported hydrogen would be lost again.
    Neither problem can be solved by microbes.
    It would take millions of years for this to be a problem. A few million years is a very short time in terms of the life of a planet, but for human purposes it might as well be infinite.
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    Quote Originally Posted by Scifor Refugee
    Quote Originally Posted by Twit of wit
    2. Lack of magnetic field to shield the atmosphere from being blown away by solar wind. Without it, any imported hydrogen would be lost again.
    Neither problem can be solved by microbes.
    It would take millions of years for this to be a problem. A few million years is a very short time in terms of the life of a planet, but for human purposes it might as well be infinite.
    I have seen, but can no longer locate, research that suggests this would happen within 50,000 years. That is more of a problem.
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    Quote Originally Posted by Ophiolite
    I have seen, but can no longer locate, research that suggests this would happen within 50,000 years. That is more of a problem.
    Ditto for me on it taking millions of years...I guess we'll see who bothers to dig up a reference first :wink:

    People make too big of a deal out of the magnetic field thing. Note that Venus has no magnetic field, but still sports an atmosphere much thicker than Earth's, despite being much closer to the sun and therefor getting hit with many more charged particles. As I recall, that same source that gave millions of years for Mars also had calculations showing that even the Moon could hold 1 ATM of atmosphere for about a thousand years, if someone were to dump enough gasses on it.
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    Quote Originally Posted by Scifor Refugee
    People make too big of a deal out of the magnetic field thing. Note that Venus has no magnetic field, but still sports an atmosphere much thicker than Earth's
    Even Venus with it's thick atmosphere has almost no hydrogen, even less than Mars. (and that means no water)
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    Quote Originally Posted by Twit of wit
    Even Venus with it's thick atmosphere has almost no hydrogen, even less than Mars. (and that means no water)
    I believe it is generally agreed by astronomers that Venus had liquid water for a very long time, at temperatures much higher than you would find on Mars - perhaps as recently as a billion years ago. As I said, it takes a loooong time to strip away hydrogen like that on a planet with any significant gravity. Mars has lower gravity, but it's also a lot farther from the sun and so receives less solar wind. On human time scales, any water/hydrogen that we added to Martin atmosphere would be essentially permanent.

    Edit: Heck, forget Venus. Many astronomers seriously believe that much of Mars was covered with oceans billions of years ago. If it was impossible for Mars to maintain water in its atmosphere for any significant length of time, this theory would be a non-starter.
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    Actually there was a snippet in New Scientist a few years ago, which said that an Earth density atmosphere on the moon would last one million years.

    This implies that a full atmosphere on Mars would last many millions. The fact that, as Scifor said, Venus has a long lasting, very thick atmosphere, backs this idea up.

    To Twit of Wit

    Earth also has next to no hydrogen in its atmosphere, but has lots of water. What is your point?
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    Quote Originally Posted by skeptic
    The fact that, as Scifor said, Venus has a long lasting, very thick atmosphere, backs this idea up.
    The interaction of the solar wind with the Venusian atmosphere generates a protective magentic field at times of hig solar activity. the effects at times of low activity have not, to my knowledge, been determined.
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    I found this on Wikipedia.

    Surface chemistry

    Results published in the journal Science after the mission ended reported that chloride, bicarbonate, magnesium, sodium potassium, calcium, and possibly sulfate were detected in the samples. The pH was narrowed down to 7.7±0.5. Perchlorate (ClO4), a strong oxidizer at elevated temperatures, was detected. This was a significant discovery. The chemical has the potential of being used for rocket fuel and as a source of oxygen for future colonists. Under certain conditions perchlorate can inhibit life; however some microorganisms obtain energy from the substance (by anaerobic reduction). The chemical when mixed with water can greatly lower freezing points, in a manner similar to how salt is applied to roads to melt ice. So, perchlorate may be allowing small amounts of liquid water to form on Mars today. Gullies, which are common in certain areas of Mars, may have formed from perchlorate melting ice and causing water to erode soil on steep slopes.
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    Quote Originally Posted by Ophiolite
    The interaction of the solar wind with the Venusian atmosphere generates a protective magentic field at times of hig solar activity. the effects at times of low activity have not, to my knowledge, been determined.
    I'm pretty sure that happens with any atmosphere - there's nothing special about Venus in that respect. It's caused by ionization of gasses in the upper atmosphere.
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    Quote Originally Posted by Scifor Refugee
    Quote Originally Posted by Ophiolite
    The interaction of the solar wind with the Venusian atmosphere generates a protective magentic field at times of hig solar activity. the effects at times of low activity have not, to my knowledge, been determined.
    I'm pretty sure that happens with any atmosphere - there's nothing special about Venus in that respect. It's caused by ionization of gasses in the upper atmosphere.
    The point is that the absence of a magnetic field may not be the deal stopper that some claim it is.
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    Quote Originally Posted by Ophiolite
    Quote Originally Posted by Scifor Refugee
    Quote Originally Posted by Ophiolite
    The interaction of the solar wind with the Venusian atmosphere generates a protective magentic field at times of hig solar activity. the effects at times of low activity have not, to my knowledge, been determined.
    I'm pretty sure that happens with any atmosphere - there's nothing special about Venus in that respect. It's caused by ionization of gasses in the upper atmosphere.
    The point is that the absence of a magnetic field may not be the deal stopper that some claim it is.
    What would happen if we were forced to colinize Mars by some Threat

    to life on EARTH ?????
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    Quote Originally Posted by atominoceanofignorance
    What would happen if we were forced to colinize Mars by some Threat to life on EARTH ?????
    we would figure out a means or we would perish.

    Do you want to be more specific?
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    Quote Originally Posted by Ophiolite
    Quote Originally Posted by atominoceanofignorance
    What would happen if we were forced to colinize Mars by some Threat to life on EARTH ?????
    we would figure out a means or we would perish.

    Do you want to be more specific?
    Yes !

    The point is less ethical and more in the aera of hipothetical aproaches especially ,

    how quickly would mars be habitable even considering selfsustaining colony

    construction of sub-surface , orbital , and surface types .
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    i may not be understanding your question, but it seems like what you're asking is "if we knew the earth was going to be uninhabitable in x years, how long would it take us to colonize mars?"

    the quickest i could see us building a self sustained colony on mars is in twenty years. now that would only happen if the species were in fact threatened with certain death on earth. at the current rate i don't envision a colony on mars for about the next fifty years.
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    Twenty years would probably be amazingly fast.

    Think of what a small self-sustaining colony would involve.
    The colony size itself would need to be tailered for long term genetic stability.

    Every system would need to be simple, reliable and heavily redundent.

    A way to get raw materials for both life support and to feed some form of industry for turning them into useful tools, buildings etc.
    A way to produce energy.
    Some means of agriculture.
    A source of food protiens
    Perhaps a library of DNA to proserve earth species with hope we'd be able to bring them back in the distant future.

    There's probably need to be a serious look at primative technologies--because they might be the most reliable for long term use.

    What a challenge....
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    the genetic library need only be preserved as data. our knowledge of synthetic biology will advance quickly enough that storing genetic information via flash drive could preserve a species which could later be re-created.

    for a means of energy, hydrogen could easily be imported from the moon which is extremely rich in it. the hydrogen could be used on mars in a fusion plant to provide more than enough energy.

    the energy could be used in a hydroponic agricultural system.

    food proteins could be generated via raising indoor livestock off of the plants, or via genetically engineered plants.

    the raw materials is a bit more complicated, further surveys would have to be done on the surface before i could begin to guess at that.

    and yes i do admit that this is under the best possible circumstances. i have faith(which is perhaps unfounded) that if the species itself were at risk we could pull together and put forth maximum effort to find some way of saving ourselves. if mars turned out to be a viable option i think we could do it within twenty years. of course i'm under the impression that the moon would be better because it contains the hydrogen for fueling a nuclear plant, and it's much closer to the earth which could possibly solve the raw materials problem.
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    Quote Originally Posted by saul
    the genetic library need only be preserved as data. our knowledge of synthetic biology will advance quickly enough that storing genetic information via flash drive could preserve a species which could later be re-created.

    for a means of energy, hydrogen could easily be imported from the moon which is extremely rich in it. the hydrogen could be used on mars in a fusion plant to provide more than enough energy.

    We have vasty different visions for sure.

    I'm thinking a couple thousand people. They be struggling to maintain enough manufacturing capacity to even keep up with life support and other things for a growing population--a long ways from having the expertise or capacity to maintain space ships to harvest anything on the moon. I think humans would be stuck on the Mars for at least a century before having anything close to the resources to go off planet again.
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    A good reference [http://en.wikipedia.org/wiki/Space_colonization] exemplifies many

    of the possable aproaches. 8) & [ http://en.wikipedia.org/wiki/Space_habitat ]
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  47. #46  
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    Quote Originally Posted by Lynx_Fox
    vasty different visions
    Allow me to contrast the two approaches.

    The first approach is an extension of our current aerospace programmes. Human life is sustained within an entirely man-made, closed system. It's all done with gadgets. This requires an enormous mass of machinery, both manufacturing on Earth and accelerated out of our gravity well. The fact that to build and maintain all these components requires the combined industry of large, industrialized countries, tells us that a self-sustaining colony of the aerospace type must include each element of a large industrialized country... i.e. if the hydroponic farms need various replacement rubber gaskets, and the farm workers need rubber boots, the colony must include a gasket factory and a rubber boot factory. This stuff doesn't grow on tress, so it will be more difficult to produce apart from Earth.

    A century ago we expected that with industrial progress, soon machines would do all the work for us. However we find ourselves increasingly caring for the products of industry, including the machines which we must build, operate, maintain, and dispose of. We work for them. Throwing more of them at the problem hasn't lessened our workload.

    In an aerospace-type colony the artificial environment compels colonists to maintain the artificial environment.



    The second approach to extraterrestrial human colonies, is an extension of our natural way of life. We exist as the apex species within a much larger naturally self-sustaining biome. The bulk of this biome is only indirectly relevant to human survival. Since the "machine" of Earth's biosphere needs only passive assistance from humanity (e.g. carbon dioxide, poop), our work is simply to skim the fat of it, in the most sustainable way possible.

    So the idea is to catalyze the formation of a natural biosphere. Then colonists enter to exploit and expand within the self-sustaining system. Ideally this biosphere would offer primitive habitat for humans, so we could thrive with modest investment from Earth-based industries.
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