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Aerospace New Ideas for shelding:manned deep space Missions

  1. Jun 24, 2004 #1
    One of the many difficulties in haveing a manned deep space mission is that durring the course of the trip, you are very likely to be hit by a large number of micro meteorites, which would penetrate the hull and start decompressing your ship. Hence we need a solution that will match these peramitars.

    1. must be able to temperarily seal a breech in a vessle very quickly.

    2. must be capable of telling the onboard personel where the breech is.

    3. if the area is breeched and repaired it must be able to function in the same capacity again.

    some of the guidlines that are prefferable.

    1. keep the weight of the system under 30% of the entire ship.

    2. use current technology.

    3. Cost effective

    My solution:

    Build cells that are about 6 inches wide, six inches long, and 3 inches deep. fill each one with a gell that as the temperature decreases then the volume decreases and the viscocity increases (basiclly it expands and freezes solid.) that way if it is hit in a single cell then the gell will expand and block the leek, and then the astronauts can seal the hole at the next conveniant time. If one of the conjoining sections is hit then the jell from all of the boardering cells will fill the gap, all of these cells will need to be replaced. the cell design is so that the replacementwould be easyer. each of the cell walls should have minute sensores through it so that it can scence A) the gell changing pressure drasticly, or B) a break in its sensing curcits. that would be then fed into a display that will tell the piolet where the breach had occured.

    give your oppinions on this Idea, and give other Ideas if you have better ones.

    P.S. the problem that I already see with it is weight and cost (which are intrensicly related).

    have a good day
  2. jcsd
  3. Jun 24, 2004 #2


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    Hi griffin,

    It is my understanding that MLI already does a good job of protecting against micrometioroid impacts, in addition to providing thermal control.
  4. Jun 24, 2004 #3
    Since your "liquid" is dependent on cold temperature as an activation switch, you also need to consider situations of intense heat such as entering Earth's atmosphere. Sealing the hole at the next convenient time is also not a good remedy because space walking is not a trivial task, but rather an unnecessary danger. Personally, I don't think temperature is a safe activation switch.
  5. Jun 24, 2004 #4
    the only other thing I could think of is if it hardened when pressure decreased.

    I don't know very much about current sheilding technology, but I did attend a lecture, and one of the key points that were mentioned inhibiting long term space flight outside of earthes immediate vacinity was sheilding. I know that in earths orbits it is not nearly as bad of a problem as it may be a little further out. (I heard one theory that the moon acts as a relativly good vacuum cleaner for meteorites and the such.)

    thanks for the critacisums though, that is how lousy ideas become working solutions to real problems.
  6. Jun 25, 2004 #5


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    Greetings !

    A few comments:
    Deep space missions are problematic from the standpoint of
    radiation shielding. Beyond Earth orbit and farther from planets/
    moons yet still in the solar system and relatively close to the
    sun - radiation of all forms is high and very considrable shielding
    is required.

    Meteorites and space junk are of greatest danger in LEO. There's
    a huge amount of them there today and it's getting dangerous
    and risky for manned and unmanned spacecraft.

    Your idea may be applicable for some applications. For manned
    spacecraft, however, a panetrating piece of material could damage
    equipement or kill a person, so you must have real armour.
    On the other hand, if for example, you wanted a large closed
    space with some gas inside and no people, ussualy, then this
    would be great and could save lots of dollars.

    I don't think that reentry heat is a problem here. If you're going
    back down with this stuff you won't be using it as a heat shield.
    Also, any panetrating piece of material will abviously, at velocities
    of several km/sec, produce lots of heat witht the right "gel", to
    seal it off while tempratures of a few hundred degrees - when
    exposed to the sun for a while, could still be too low for that,
    again - for the right "gel".

    This could be a good idea for one of'em settelite repair/construction
    manned station ideas, where the spacecraft are "parked" in this
    large pressurized breatheable air volume.

    Check out "aerogel" types, might fit.

    Live long and prosper.
  7. Jun 25, 2004 #6
    Paper Layer Stuff???

    I thought a bunch of NASA guys sorta had a solution for this on the space staion by having layers and layers of paper kinda stuff. If however, it was seriously damaged, the astronauts could go out and "paste" another layer on.
  8. Jun 25, 2004 #7
    This idea is probably decades away but not unrealistic: plasma shields. I read a few articles on it online, I can't remember the site off the top of my head but try typing in "plasma shields" or just "force fields" in google and something might come up. I'll try to find it later.

    Anyways, it uses a super strong magnetic field to channel charged plasma around the ship. Small particles get deflected or burt up in it. Also the strong magnetic field can also deflect charged cosmic rays that could hurt the crew.
  9. Jun 25, 2004 #8


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    Yep. It's called multi-layer insulation (MLI).
  10. Jun 26, 2004 #9


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    Yeah, I believe they wanted an inflatable sleeping module
    or something. But gel sounds cooler... :wink:
  11. Jun 26, 2004 #10
    I believe an electro-static "aegis" would be perfect for protection against cosmic rays and solar flares. We're quite advanced enough in electrostatics to start a new engineering feat that could benefit highly for the space-faring homo sap.

    How could it work?

    You could charge up an electrostatic grid, akin to the one on the Deep Space probe's NSTAR ion-engine, to a high positive potential. From what I've heard, the most dangerous stellar particles are accelerated protons, with kinetic powers surpassing many modern particle accelerators today. If that relativistic proton touchs your aegis, it can be slowed down just enough to prevent biological damage to humans.

    Or you could just live in a LH2-fuel tank for days on end.

  12. Jun 26, 2004 #11


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    You also have neutrons which are much much harder to stop,
    not just alpha particles. Anyway, if we can't create such energies
    on Earth then we sure ain't gon'na create them on a small spacecraft
    between electrdes that surround it.

    Live long and prosper.
  13. Jun 26, 2004 #12
    Actually we can create such magnetic fields pretty easily on earth. The earth's magnetic field deflects large amounts of cosmic rays and we've created magnets thousands of times more powerful than earth's magnetic field.

    As for power, perhaps solar couldn't supply a sufficent magnitude of power despite it's abundance. But nuclear and fusion could easily supply enough power. Who cares about dumping radioactive material into space, its already full of radiation. Just as long as you're in deep space and not near Earth. And you could easily use the magnetic field that shields you to also suck deutrium ions into a fusion reactor. The magnetic field would be so wide you could easily gather enough deutrium atoms just from the emptiness of space. Killing two birds with one stone.

    I also had this neat idea of a "neutrino reactor." If a substance could be found that reacts heavily with neutrinos (not likely to happen any time soon) it could harness their power. Seeing how their so abundant anywhere in the universe you would never really need to worry about fuel. But I did some research and according to my calculations you could only really generate around 40J of energy per square meter. I don't think it will ever happen but just an interesting thought.
  14. Jul 29, 2008 #13
    I would have to agree with drag. Armour is the best for stopping micrometeorites, and it has been tested before in the Deep Impact mission impactor. The armor used in that case were simply sheets of copper that prevented small debris from interfering with the instruments. It was copper, because copper isn't usually found on asteroids, so you can eliminate it from spectrometer readings.
  15. Jul 29, 2008 #14
    sorry, meant to say comets
  16. Jul 29, 2008 #15


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    We can generate very powerful magnetic fields in very small volumes for very short periods of time. However, creating a magnetic field large enough to envelop a ship and sustaining it for months or more is completely impossible right now. The amount of power required by such a system would be monstrous.

    Magnetic shielding could be a viable route to go in the far future (greater than 100 years IMO), but would require an incredibly powerful as yet undefined powerplant. The powerplant would have to have a very large power/volume ratio, something not able to be accomplished with any standard fission reactor right now.

    It may be abundant very close to the Sun, but if we're truly talking about deep-space missions then solar power is not an option. This is why deep-space probes used up to this point have all used RTG's.

    We don't even really know how much power such a magnetic shield would require; but even if a fission reactor could provide enough power, I'm doubtful it could provide enough power in a useful volume and weight. Megawatt reactors are possible on Earth beacuse they can be as big and as heavy as needed, but such reactors cannot be retroffited for space. What use is a fission reactor in a ship if it's unshielded and is several times the size of the ship itself?

    And why would you "dump" radioactive waste in space? Not only would you increase the requirements of your shield due to localized radiation, but if you're cruising along at a set velocity so is anything you drop off your ship. You would essentially be floating around in your own home-made radioactive cloud.
  17. Jul 29, 2008 #16


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    Wow. Pretty good thread necromancy.
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