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Settling on the Moon

  1. Sep 16, 2015 #1
    What do you guys think about humans settling on the moon ???
     
    Last edited by a moderator: Sep 17, 2015
  2. jcsd
  3. Sep 16, 2015 #2

    Drakkith

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    Not anytime soon. Costs are way too high to place a permanent settlement on the Moon. Not to mention the fact that we currently don't have the knowledge of how to build a self-sustaining colony away from Earth, which only increases the cost since the colony would need to be resupplied in some fashion by Earth.
     
  4. Sep 16, 2015 #3

    Chalnoth

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    I don't think anything like this is going to happen before we have a way to get into orbit without using rockets. Rockets expend about 99% of their fuel just lifting their fuel. If we could develop a viable method to get vehicles into orbit without them having to carry their fuel with them, we could drastically cut down on costs and maybe, just maybe, start contemplating extravagant missions like this.

    There are some ideas to get around the limitation of rockets, but I don't think any have gone much beyond sketches on paper. A big issue is that some of them, such as the space elevator, are such absurdly massive engineering projects that it's going to be difficult to ever get them off the ground.
     
    Last edited by a moderator: Sep 17, 2015
  5. Sep 17, 2015 #4
    we WOULD NEED SOMETHING WHICH USES LESS fuel, cost effective and can take more people. Such kind of technology is not available but wht about a spaceship kind of thing which uses fuel like hydrogen to move . This can be use to transport astronauts to build a bio sphere in which we humans can basic needs . BUt not in near furure .
     
  6. Sep 17, 2015 #5

    Borek

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    How is it different? No matter what fuel you use (be it hydrogen or anything else) you are still limited by exactly the same problem.

    Please remember hydrogen per se is NOT a fuel, it is just one of the fuel components - it requires and oxidizer to work.
     
  7. Sep 17, 2015 #6

    Chalnoth

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    Hydrogen is currently a common component in rocket fuel. The problem is that chemical propellants simply don't attain velocities high enough to get around this problem. Nuclear propulsion is quite a bit more efficient in terms of comparing the thrust to the mass of the fuel, but there are some pretty serious difficulties with getting large enough thrust to launch from the Earth's surface (safe nuclear propulsion has low power but lasts a very long time). There are some pretty clear radiation concerns related to increasing the power.

    Some ideas I've read about that may (eventually) work out:
    1. Laser propulsion: use extremely powerful lasers to push the vehicle into orbit, or at least to a pretty high altitude. The energy requirements are pretty ridiculous, so I don't know if this will ever be feasible.
    2. Space elevator: Using carbon nanotubes, it's possible to build a tether to an anchor in orbit (presumably a captured asteroid). It would largely just be a matter of having the vehicle climb the tether to reach orbit, using a tiny fraction of the energy of an equivalent rocket. The biggest problems with this idea are that it would be an obscene engineering challenge, the carbon nanotubes are only barely strong enough (leaving little room for any engineering flaws), and the tether itself may have stability problems.
    3. Space pier: Using synthetic diamond, it would potentially be possible to build a launch platform that reaches up into the upper atmosphere. Diamond has more than enough compression strength for a structure that reaches dozens of kilometers above the surface of the Earth, so it would have some leeway the space elevator doesn't have. But it'd be an even more ridiculously massive engineering project, requiring far more material than the space elevator.

    All of these options are, today, rather absurd. They may never be done, and even if they are done eventually it could easily take more than a century to get engineering to the point where they're possible. But if we humans were ever able to get our hands on just one technology that didn't require us to waste 99% of our fuel, the solar system could easily become our playground.
     
  8. Sep 17, 2015 #7

    Garth

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    Let's not forget that some 68% of the universe's mass is in the form of Dark Energy, which repulses ordinary matter causing the universe to accelerate in its expansion, it is a form of 'anti-gravity'; now if we could only 'bottle it'..........

    Garth
     
  9. Sep 17, 2015 #8
    It would be a lot cheaper and more productive to place habitat domes (or whatever) on the currently uninhabitable parts of the Earth, such as large deserts.
    There isn't as far as we know any part of the Moon which has large amounts of resources that are not obtainable on Earth.
    There is also no science goal I can think of, so this would be just one hugely expensive vanity project for whichever nation decided to do it.
     
  10. Sep 17, 2015 #9
    THanks for ur replies and ideas ...
    2 yr back i participated in NASA AMES SPACE SETTLEMENT CONTEST 2013 and got an international rank 3 on my ideas on an orbital setllement but damn thts not possible as it requires loads of money , unbelievable number of materials and some big engineering sikils
    GUY !!! WE are talking about a city floating in space ...
     
  11. Sep 17, 2015 #10

    Chalnoth

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    Well, we do know of a way to extract energy from the vacuum: the Casimir Effect. Unfortunately, it's only an extremely short-range effect that likely has no possibility of use for propulsion.
     
  12. Sep 17, 2015 #11

    Chalnoth

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    Helium is one pretty major resource that's running out on Earth but pretty abundant on the moon. There are lots of others:
    http://www.cnbc.com/2014/04/02/the-global-race-to-harness-the-moons-resources.html

    But I'm pretty sure we need an alternative to rockets for this to become economical.

    Also, let me just say that I fully support a vanity project like building a base on the moon. There are far worse things we are spending that kind of money on (such as war). If we could divert some money to do something like that, it'd be pretty amazing.
     
  13. Sep 17, 2015 #12
    I would certainly support your view that a project of this nature, even if not very productive, is a better idea than dedicating enormous amounts of resources to wars.
    I don't think wars will end any time soon though, for some people wars are a good earner unfortunately, a moon base probably not.
     
  14. Sep 17, 2015 #13

    Chalnoth

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    A moonbase would have the same kind of profitability: the people that build the required components need to be paid.
     
  15. Sep 17, 2015 #14

    mfb

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    Fuel costs are a small fraction of the total cost of rockets. It's the structure that holds and uses the fuel that costs. Also, with ~5% payload more than 5% of the fuel is used for accelerating payload.
    There are many ideas. Personally I like the StarTram approach, but it would be a massive engineering project. Not the biggest one, however, and not the most expensive one either.
     
  16. Sep 17, 2015 #15

    DaveC426913

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    Everybody's concentrating on HOW to go to the Moon. What about the less obvious question of WHY go to the Moon?

    As a starting point, ask an even easier question: why not settle in Antarctica? It's remote, virgin, a lot like the Moon, only thousands of time cheaper, and opening a door won;t kill everyone in under a minute.

    I'm not promoting moving to Antarctica, I'm simply pointing out that there's got to be compelling reasons to put up with the inconvenience and danger of moving to a remote, hostile place.
     
    Last edited: Sep 17, 2015
  17. Sep 17, 2015 #16
    In most sci-fi universes, the Moon is either terraformed or possess some unique natural resource that requires a large colony for extraction.
     
  18. Sep 17, 2015 #17

    Chalnoth

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    Why climb mount Everest?

    As for Antarctica, we do have habitats there, largely for scientific purposes. If we could make it reasonably economical to get to the moon, the moon would be an *amazing* place to do astronomy, for largely similar reasons that quite a bit of astronomy is done in Antarctica.
     
  19. Sep 17, 2015 #18

    DaveC426913

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    Yeah, but this is about settling - as in: making homes, jobs and futures.

    Right, but it's a thousand times more economical to settle Antarctica, and yet we don't start colonies there.

    Again, I'm simply pointing out that the reasons we don't settle the Moon are the same as the reasons we don't settle any other less-than-hospitable place. We just haven't run out of room or resources here yet.
     
  20. Sep 17, 2015 #19

    Evo

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    Because some people have more money and spare time than they know what to do with and would rather do something selfish instead of helping others.
     
  21. Sep 18, 2015 #20

    Chalnoth

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    Running out of room or resources will never be a reason to settle on the moon or anywhere else outside of the earth. There just won't be any way to transport enough people to make any difference. The only reason that will ever make sense is adventure.
     
  22. Sep 18, 2015 #21
    When I think of a moon base I don't think about ordinary people living and working there at all, I just think of it as the next step after the ISS , why do we go to ISS ? to do research on the effects zero of gravity etc on the human body etc and to conduct many other experiments . It can also serve a stepping stone to go to Mars. Martian geology and history is far more interesting for scientists now compared to the moon , we can learn how to manage the technical difficulties in a mission that can take years to complete, Mars might offers some unique challenges that the moon can't prepare us for , there are also discussions on the possibility of making rocket fuel on the moon using the water and other stuff available there but I don't think we have profitable methods for extracting them yet. http://www.dailymail.co.uk/sciencet...n-craters-help-signal-presence-lunar-H2O.html
     
    Last edited: Sep 18, 2015
  23. Sep 18, 2015 #22

    phinds

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    Yes, but this thread is about reality and actually, not fictionally, colonizing the moon. What does sci-fic have to do with that?
     
  24. Sep 18, 2015 #23

    DaveC426913

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    Perhaps I'm just putting emphasis on the OP's choice of the word 'settling'. I interpreted it to mean a place ordinary people could visit, or scientists could have as a home, not just a few months' rotation, like the ISS. Perhaps marry, and have children.
     
  25. Sep 18, 2015 #24
    Maybe the OP was a little vague, anyway if we build an ISS on the moon (LSS) given the amount of money and resources it will take, it will be a permanent base on the moon although it's inhabitants will be moving in and out.
    We will need some kind of a profitable industry on the moon to keep the base running if we want a large scale human 'colony ' where ordinary people can live work and reproduce, I can't think of any profitable industry right now with current technology.
     
  26. Sep 18, 2015 #25

    DaveC426913

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    More like ILS. :wink:
     
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