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Mars to stay

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  1. Jun 24, 2012 #1
    Moderator note: Please read post #9 by DH before replying to this thread. This thread will be closely watched by the mentors


    According to wiki

    See, I think the first mission of a crew four is too risky. You need a lot of people so that one person can mutually benefit from the labor of a large team. I say send every two years (since the window for flying to Mars is once every two years) about 60 in a huge fleet of about 15 ships. It looks like one ship costs about 10 billion dollars, so 150 billion split among about 20 nations is certainly doable. Sending 4 people is just too risky. The likelihood of death is too high. In order to settle this alien world you're going to have to do it in a major way, make a huge effort because the obstacles are enormous. I'm reading Robert Zubrin's book The Case for Mars right now and it is a real adventurous read.
     
    Last edited by a moderator: Jun 25, 2012
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  3. Jun 25, 2012 #2

    Drakkith

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    Robert, while your enthusiasm is commendable, I feel I should point out that we don't even know how to land a manned vehicle on Mars yet, let alone 15 vehicles. Plus the funding required for such a project is enormous. 150 billion is a staggering cost for something that we don't even know how to do yet. The first manned missions to Mars will most assuredly consist of the smallest crew possible, while covering all aspects of essential mission skills and emergencies. Any extra crew members simply take up space, weight, and resources, which make it that much harder to ensure the mission is feasible.
     
  4. Jun 25, 2012 #3

    To my mind there is so much work to be done to get the colony up and running. The only way to get a lot of work done quick is with a lot of people.
     
  5. Jun 25, 2012 #4

    Drakkith

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    The bottleneck to establishing a working colony will not be the number of people, but the amount of resources that we can carry there. It is not possible to use the natural resources on Mars to establish ourselves yet, so we must carry practically everything we need with us. Also consider that the more people on the mission, the more resources will be needed to support them. This runs up the weight requirements of a missions very very quickly. Take too many people and the amount of food, air, water, and other necessities increases the required fuel to launch and land drastically. And that extra fuel also requires more extra fuel to lift it into space, so the weight of fuel quickly compounds to absurd levels if you aren't careful.
     
  6. Jun 25, 2012 #5
    I guess the question is how many is too many. Two colonists does seem a tad too few, while your 60 seems a bit high as there would then be a need for a colonial political framework of sorts to administer the workload on the colony. And if the colony does not 'work out' for any unforeseen reason then that is 60 people that have to be transferred back to earth - what if the funding from the 20 nations dries up due to recession or conflict. You should note that with space exploration doing things quickly is not part of the vocabulary.
     
  7. Jun 25, 2012 #6

    You need to read Robert Zubrin's book first to investigate this claim, although with a grain of salt since he clearly sees Mars through rose colored glasses. All the elements we use on Earth are on Mars, especially Carbon Dioxide since the atmosphere is 95% CO2. Admittedly it will take quite a lot of work to get real industry set up but Mars has the elements. It seems to be rich in silicon and deterium which is necessary for fusion, although building a fusion reactor of course cannot even be done on Earth yet.
     
  8. Jun 25, 2012 #7

    D H

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    That's a fallacious argument. The elements and compounds needed to sustain human life do not exist anywhere close to the same proportions on Mars as on Earth.


    [strike]Thread locked pending some ground rules for discussion.[/strike]
     
    Last edited: Jun 25, 2012
  9. Jun 25, 2012 #8

    D H

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    Here are the ground rules.
    1. No Picardish "make it so" kinds of statements.
      Do not simply handwave a vague suggestion into a "legitimate" proposition. Answering legitimate problems (e.g. impracticality of transporting factories, lack of water, insufficient propulsion, no closed ecosystem etc) with utterly non-trivial propositions presented as trivial (e.g. self-replicating probes/in-situ resource utilisation, piping water from polar caps thousands of kilometres, building VASIMR/fusion drives, planting crops in a domed greenhouse etc) is counter-productive.

    2. Understand the difficulties.
      Anyone who wishes to argue about "we can do that" must first read the wikipedia article on technology readiness level (http://en.wikipedia.org/wiki/Technology_readiness_level) and must understand that TRL 1 to 3 means "we can't do that". Examples: A Bussard ramjet has been rated by some as TRL 2, a space elevator as TRL 3. We can't do either one except in a science fiction novel. TRL 4 is when one can first start thinking "yeah, we might be able to do that". Reaching TRL 6 is where "we can do that" starts. TRL 6 is the minimum level for all technologies needed for a human mission to Mars program.

    3. Understand the risks.
      Getting unmanned vehicles to Mars is a risky endeavor. Sixty percent of the missions to Mars have failed. Even though getting to Mars is TRL 9 (we have done it), this is an unacceptable failure rate. How are you going to address the risks? How are you going to eliminate the unknowns?

    4. Understand the costs.
      Don't just brandish dollar numbers around without any justification. You need to back those numbers up. Note that getting low TRL technologies that are essential to the mission to TRL 6 is a part of the cost. That's just part of the battle. You need to get things to TRL 8.

    5. Understand the human factors.
      Russian cosmonaut Valery Ryumin said it best: All the conditions necessary for murder are met if you shut two men in a cabin measuring 5 metres by 6 and leave them together for two months. How do you deal with this?


    Just some of the things we know we don't know how to do: how to land large vehicles on Mars, how to do precision landing on Mars, how to utilize the natural resources on Mars (in situ resource utilization), how to provide power for years on end, how to grow food on Mars for years on end. Just a couple of the things we know that we don't know: Is there life on Mars, and if there is, is it hazardous? How toxic is Mars dust?
     
  10. Jun 26, 2012 #9

    Ryan_m_b

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    My knowledge on the technical side of aerospace is limited so I'll try to stick mainly to what I know. Firstly though I'd like to offer up a distinction and some definitions which should nip confusion in the bud:

    - Outpost
    A manned habitat that is reliant on supply.

    - Colony
    A self sufficient settlement.

    The difference here is huge both in purpose and requirements. An outpost on Mars would require us to be able to affordably send regular supplies of food, water, air, equipment (mitigated as much as possible by in-situ resource utilisation) for a small group of people whereas a colony would require hundreds of thousands to millions of people, an entire industrial base and a closed ecosystem. I'm going to take it as read that we are mainly discussing the former rather than the latter but I feel this is worth mentioning because a lot of discussion surrounding this topic is done with the idea of space colonisation in mind. In my experience this affects how the conversation progresses with people that have colonisation in mind viewing any other space endeavour as a means to this end producing different thoughts and suggestions.

    EDIT: Something I forgot to mention, personally I feel that any discussion regarding a Mars mission should start with a proposal for what the purpose of the mission is going to be. Let's not take it as read that a manned Mars mission is somehow an end in itself rather than a means.
     
    Last edited: Jun 26, 2012
  11. Jun 27, 2012 #10
    Why go to Mars in the first place? Where is the profit? The Moon or the atmosphere of Venus are better alternatives in my view? I bet the blame should be put on Orson Welles!
     
  12. Jun 27, 2012 #11

    Drakkith

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    It isn't about profit currently, just like going to the Moon wasn't either. Commercial interplanetary travel is not profitable at this time.
     
  13. Jun 28, 2012 #12
    I think its a question of perspective...Having presence in space and ability to prevent threatening comets from destroying life on earth is very profitable!
     
  14. Jun 28, 2012 #13

    Drakkith

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    Having a presence in space, whatever that means, does nothing to prevent comets from destroying the Earth.
     
  15. Jun 28, 2012 #14

    D H

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    Stay on topic, please. No more posts about "why not Mars", no more posts about human presence elsewhere in space, no more posts about no humans in space period. Start a new thread.

    Making the case for sending humans to Mars is fine. Justifying a technical proposal is an important part of any technical proposal. Saying the money is better spent elsewhere -- that's the job of the evaluators of competing proposals, the job of the of Congress to allocate money amongst all of the competing needs and desires for the limited federal budget.
     
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