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Theoretical Application For Acceleration In Space

  1. Sep 23, 2009 #1
    I have just came up with the following idea which can, with the proper equipment and technology, be applied in space in order to produce immense acceleration for a specific body/bodies:

    STEP 1:
    Number of engined spacecrafts will be placed in one dimension, in equal distances from one to another (for instance: 6 or 8 spacecrafts, creating hexagon or octagon), heading toward the same direction in parallel lanes and at the same velocity.

    STEP 2:

    The spacecrafts will be connected with a flat net or a consecutive material which will be considerably very resistable, yet extremely flexible. The thickness and surface should be optimized to best fit the required goal, which will be as follows.

    STEP 3:
    This application can be used for two situations I have came up with:
    (1) A probe/spacecraft/any other optional device sent to space for a particular purpose will be flying directly in the opposite direction of the spread net and the spacecrafts. The body will then hit the net, forcefully enough to create a tremendous elastic force which will, eventually, cause the object to fly in reverse (the same direction as of the net-carriers) and continue its travel with great speed.
    (2) same course of events can also be applied to prevent an astroid hitting the surface of the earth - changing its path, by stretching the net in space in the right angle by maneuvering the spacecrafts.

    Of course this can be modified, but the idea is very simple actually.
    Any comments regarding this are accepted, including corrections, suggestions, modifications et cetera.
    Last edited: Sep 23, 2009
  2. jcsd
  3. Sep 23, 2009 #2
    How is this more efficient than using engines alone? For one thing, those net carriers would also need to pull on that magical material, in order to obtain some elastic effect.

    Also, shouldn't this be in engineering?
  4. Sep 23, 2009 #3
    Imagine a baseball being thrown very hard on a vertical trampoline. Now with the lack of air which causes friction in space, this impact should accelerate the object very efficiently in terms of time, energy and costs.

    As for the engineering issue: well, I assume that is correct, though I think it could also be discussed in the field of astrophysics when taking in count the given environment in outer space and the similarity this notion has with gravitanional pull of celestial objects in the universe.

    More comments, make this discussion fertile people.
  5. Sep 23, 2009 #4
    In order for your idea to be effecient (I will not even discuss its practicality) you have to violate three of the most important physical laws:

    1. if the net is elastic, therefore a displacement will occur at the impact and energy will be consumed and lost in the diplacement, otherwise it will have to violate the conservation of momentum

    2.even if the net was a solid wall that no displacement will occur, a perfect collision can never occur, otherwise it will have to violate the kinetic theory of gases

    3. even if we assume a perfect collision were no energy will be lost (consumed) at this case the object will reflect at exactly the same energy that it has before the collision and there will be no benefit from the whole mechanism, otherwise it will have to violate the second law of thermodynamics
  6. Sep 23, 2009 #5


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    I guess you get points for originality as I've never heard of anything like this before. Unfortunately for you, HossamCFD's post outlines why.
  7. Sep 23, 2009 #6
    I understand my fatal mistake here. Thank you for the extended clarification, I appreciate it.

    What about the second use i mentioned - changing the path of an object which makes its way towards earth? Does that scenario violates any physical laws in pratice?
  8. Sep 23, 2009 #7


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    It doesn't violate any laws of physics, it's just completely impractical. The material aspect aside, if you're throwing up a bunch of rockets anyways, why not use them to directly attach to and move the asteroid? The material aspect not aside, you're talking about changing the momentum of an object with the mass of a mountain moving at 10km/s.
  9. Sep 23, 2009 #8
    Cosmicon, don't be dissapointed by these ideas. I also had my share of ideas violating every physics law that we know. that's because I come from an engineering background not physics (I would guess you do too). just remember that you can never create energy, you can only transform it from one form to the other.
  10. Sep 24, 2009 #9
    Okay, one more utilization I would like to porpose in this discussion:
    The net setup could be used to extract astroids from the astroid belt in our solar system, and carry them to earth (for a more punctilious analysis of them, and perhaps quarrying the minerals within) Of course it depends on the mass and velocity of the objects being carried, but even large ones can be enclosed in carriers and penetrate Earth's atmosphere with no harm.

    Or maybe attached rockets are more efficient in this case as well?
  11. Sep 24, 2009 #10
    A net in space would definitely be useful for 'herding' very small asteroids. For instance, instead of drilling a big asteroid for mining purposes, you could blow it up and pick up the smaller pieces with that net, taking them to a nearby station for processing. Kind of like asteroid mining went down in the X games.
  12. Sep 24, 2009 #11
    Yes that's my point. "Astroid fishing", you may call it. And it will most definitly be a nutritious catch, scientifically and in terms of civilization progress.
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