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Occupying Space

  1. Oct 22, 2013 #1
    We see movie after movie, and some of them are awesome, some of them are just flat our ludicrous. But...on a serious note....why haven't we occupied space yet? What's holding us back? Is it simply money? Would money be the limiting factor? I don't think our technology is limiting us, as far as I can see we could successfully and effectively occupy space right now without any hassels.

    What are the challenges we need to overcome to occupy space like we do earth?

    1. Gravity
    A. Solution: Rotate the station or ship. Rotating the station or ship causes objects to push against the hull. At a calculated rotation, a ship could 'simulate' gravity simply by rotating.

    2. Resources
    A. Solution: Food, drinks, whatnot, would have to be grown in outer space. They 'could' be transported back and forth from Earth, but it would be much cheaper and more economic to grow our own foods in space. I imagine a floor or two, or three, of the station could be dedicated towards food production.

    3. Navigation
    A. Solution: NASA has recently revealed an interesting way of using our own universe as our navigation, no extra stuff needed. We just use Pulsar Stars to pinpoint our location.

    4. Fuel
    A. Solution: The problem is, most fuels aren't renewable. While we could import the fuel from Earth, I would think that mining certain chemicals from nearby planets would be more feasible, plus give us a great opportunity to study those planets as well.
    B. Problem: Without fuel, we can't fire thrusters, we can't power engines....we will die.

    5. Power
    A. Solution: Several advancements in power utilization and consumption are on the rise. However, we haven't seen it come to light as of yet. One such solution would be the 3D alloy for bateries that increases a battery's power output by a very large factor.
    B. Problem: We're still using the old fashioned power sources generations old. We need something new that we can mass produce in space.

    6. Protection
    A. Solution: Stations and ships can be equipped with weapons of such to protect against objects such as metors.
    B. Problem: Shooting crap in space can be very dangerous for everyone.

    7. Money
    A. Solution: Star Trek uses a form of economy that doesn't use the monetary system. Instead everyone works for the good of the whole and generally loves what they do. They study for advances in knowledge and understanding, not for personal gain.
    B. Problem: Everything takes money because of the notion that everyone owes everyone else something in return for their services, which works. I do something, you pay me for it, I spend some time doing something for you, you pay me for it, I make a product, you pay me for it. With Supply and Demand, nearly everything in a space economy would be outrageously expensive unless a different monetary system is established to make the system functional.

    That's all I can think of off the top of my head. Does anyone else have any other ideas? Is there a group out there that's currently working on making this possible? Why do you think we haven't done this yet? What's holding us back?
  2. jcsd
  3. Oct 22, 2013 #2
    The same reasons we don't occupy the ocean. There just isn't a need for it and you've listed most of the factors with trying to inhabit space. There's nothing going for us in space...
  4. Oct 22, 2013 #3
    Quite the contrary. The ocean has a great deal to offer, and a great deal to discover. Space has that times billions. What we can discover in space could benefit mankind immensely. The benefits of exploring space has contributed to nearly every single aspect of life. From our ability to accurately predict weather, to our understanding of the universe, to uniting countries that would otherwise be at each others' throats, and much much more. The mere ability to get a much firmer grasp on science through this is a huge reason why space exploration and inhabitation is a necessity.

    On top of that, I don't know anyone who would pass up the opportunity to safely view another planet in our solar system if they had the opportunity to in real life. Further more....what's out there? The entire idea of searching for signs of life in the great beyond shows why inhabiting space is important. How do we ever expect to travel among the stars if we do not therefore intend to live among them as well?
  5. Oct 22, 2013 #4
    The OP isn't talking about living on other planets. He is talking about being stuck in an orbit around earth
  6. Oct 22, 2013 #5
    Don't know if you realized it or not, but I am the OP, and I'm talking about Occupying Space, not "just" being stuck in an orbit somewhere around a planet. I'm talking about Occupying Space in every aspect.
  7. Oct 22, 2013 #6


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    Needs a minimal ship size -> money

    So far, we did not manage to establish a closed ecosystem with humans that ran for years. And this on earth, where building material is nearly for free, where you have gravity for free, where thermal management is easy and so on. This won't be easier in space.

    Not an issue at all.

    -> money

    Photovoltaics is certainly interesting, nuclear reactors could help for larger stations. Batteries don't store enough energy.
    Space is BIG. The big objects (>1m) are so rare that you will never hit one unless you actually aim for one. The small objects (centimeters or smaller, especially <1mm) are too small and too numerous to track them. Your ships have to survive those impacts. A ship with a diameter of 1km (that is huge) will get hit by a 10cm-object on average once per 5000 years, and by a 50cm-object once per ~500 000 years.
    It does not matter if you use money or not. You need a lot of skilled workers, working on space exploration for many years. And they all need food, a home, and all those other things we enjoy today. Currently we just don't have the capability to start a large-scale expansion to space. While there are certainly interesting things you can do in space, this is not something we can do in a reasonable way with our current technology.
  8. Oct 22, 2013 #7
    Then the biggest problem is resources and money. You might be interested in MarsOne.
  9. Oct 22, 2013 #8
    Thanks for the responses fellows :)

    I actually think the power issue can be solved along with the gravity issue. By rotating the station enough to generate centripical force, you could cause a part of the station to not rotate, and allow the rotation to run along with magnets to create a sort of generator. This would be able to create at least a baseline constant power surge without really needing too much fuel to operate it.

    I will agree that things are very technical and experts need to be managing those things. I think, however, that this is not a failure on our current technology as much as it is a colosol failure in our education system. My thought is that the reason we have "Generation Y" is because children are growing up around all the technology, therefore they know it and understand it very well. I feel that the same mentality could hold true for people who are perhaps born and raised in a space station type environment. They will better understand technical problems than those who are born on earth.

    I think a reasonable solution to the problem of people staying in space long term would be doing deployments, where the person will return to Earth after maybe a five year mission term. Food and whatnot will still need to be perfected, but I've always heard this of doing daunting tasks:

    "Do the thing, and have the power. Do not the thing, and have not the power." ~Ralph Waldo Emerson.
  10. Oct 22, 2013 #9


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    That would slow rotation.
    Energy is the main issue, power is just a matter of energy management.
  11. Oct 22, 2013 #10


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    Since you totally ignored the biggest problem, i.e., Special Relativity, I'm guessing you haven't yet studied that subject?

    If you have indeed studied it, then...

    Exercise: estimate the mass of the rotating space craft from the movie "2001 -- A Space Odyssey", and the amount of fuel required to accelerate it from rest to, say, 10% of the speed of light.

  12. Oct 22, 2013 #11
    What dude? We're not going the speed of light here, it's stationary and rotating. You don't need to go the speed of light to get 1g of centripetal force to simulate gravity.

    And no, I didn't skip that subject, I'm pretty solid in it.
  13. Oct 22, 2013 #12


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    I was alluding to travel to other solar systems with habitable planets...
  14. Oct 22, 2013 #13
    That's entirely theoretical and not really science fact as of yet. However, the Alcubierre Warp drive would solve that problem.
  15. Oct 22, 2013 #14


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    Anybody else want to get in before the lock? (IBFTL)
  16. Oct 23, 2013 #15


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    OK, I'll do one more, only because this is the GD forum for general amusement...

    If you mean special relativity is "entirely theoretical and not really science fact as of yet", then... all I can I say is: <crackpot!> <crackpot!> <crackpot!> ..... :rofl: :rofl: :rofl:

    Slight problem of how to make some negative mass... :rofl:

    ... and the crackpot klaxon continues... (until Berkeman locks the thread)... :biggrin:
  17. Oct 23, 2013 #16


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    Whenever I see or hear questions like this I feel the need to step back a bit and ask the first question: Why should we colonise space?. Establishing a manned presence for science is one thing but to build a colony of some sort is going to require orders of magnitude more resources. Enough to sustain hundreds of thousands or even millions of people to provide the specialised labour a high tech society needs, enough to design and build a fully sustainable ecosystem, enough to ship mega tonnes of infrastructure etc etc.

    Colonise the deserts and the ocean first, then get back to me about the practicality of colonising space.
  18. Oct 23, 2013 #17


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    We don't have the technology.
    We don't have the need.
    We don't have the knowledge.
    We don't have the money.
  19. Oct 23, 2013 #18


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    I love this, so concise.
  20. Oct 23, 2013 #19


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    "Space is big. Really big. You just won't believe how vastly, hugely, mindbogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space, ..." Hitchhiker's Guide to the Galaxy, Douglas Adams.

    Occupying space requires tremendous resources - oxygen, water and food - are absolutely necessary. Then there is the infrastructure - a closed system which necessarily includes waste management via recycling. Energy could be obtained from the sun, which would be most practical near 1 AU, but not so practical further out. Lack of gravity is a problem since the human body deteriorates without gravity (a rotating station doesn't necessarily do it), and then there is radiation.

    Figuring out the cost requires a realistic assessment of the resource requirements (in terms of kg), and then a reasonable rate ($/kg) to get those resources from earth's surface to destination. A figure of merit a few years ago was $10,000/kg. If one person requires 10,000 kg (10 Mt) of resources, the cost is roughly $100 million per person.

    One should investigate the cost of missions to Mars from small exploratory to full colonization. The trick of going to other planets (in our solar system) is the requirement of dropping back into a gravity well, and then leaving again. Beyond Mars, there's not much in the way of places to go.

    It's not the same as Occupying Wall Street.
  21. Oct 23, 2013 #20
    This. Just this.

    I love reading these posts about colonising space. Especially funny about growing our own food in space - because we have done such a good job at understanding/protecting ecosystems on earth. I love the trivialisation of economical and technical requirements.

    Although I have to praise the high ideals and I think this is something we can strive towards over the next few centuries - assuming we manage to get a grip on the state of the planet.

    I think I will be lucky to see a human on Mars in my lifetime let along humanity being ACTIVE in space.

    OP - Please do not mention the Alcubierre drive, of if you do just call it the Warp Drive or Hyperspace travel because it has about as much scientific basis as these do. The drive proposes using Exotic materials which may or may not exist and has no basis in any scientific discussion.

    One thing you did not account for in your original list was Psychological/Physiological factors any long term crew would experience. These go way beyond just simulating gravity.
  22. Oct 23, 2013 #21


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    This thread was supposed to have been closed yesterday.
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