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Parachute in space

  1. Jan 3, 2009 #1
    just as a minor thought i brainstormed on the deployment of a parachute in deep space. because their is no air or molecules like that, THAT I KNOW OF. would the parachute deploy?
    would it expand and fill with anything like on earth? my thoughts were that if sound cant travel in space without a medium than a chute couldn't open, at least uniformly and fairly evenly like they do here without that same medium. maybe the momentum alone could do it?
  2. jcsd
  3. Jan 3, 2009 #2


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    If we're thinking of space as purely a vacuum, which it seems you are, it seems to me that absolutely nothing would happen.

    It depends on how the parachute deploys. If it is somehow shot backwards behind the craft, it would simply sit there with any residual formation from the explosion which propelled it behind the craft. I'm not sure, but I think earthbourne parachutes are just unhitched and the air resistance takes care of the rest. Since there is no air resistance, if this is the case, absolutely nothing would happen.
  4. Jan 3, 2009 #3
  5. Jan 3, 2009 #4
    nice. its mostly as i thought itd be. I dont know how i forgot about solar wind. not the same but the idea is there. thanks a lot guys!
  6. Jan 3, 2009 #5
    In the atmosphere, the air molecules collide with the parachute, causing it to open up and expand. Since the parachute is "pushing" against the air molecules it causes it to lose momentum that it gains from gravity and thus slows it down. Basically, the faster the parachute is falling down, the bigger the pressure difference between it's top and bottom, and so it experiences more upward force, which causes it to slow down. In space, however, there are no air molecules, and no pressure of any kind, so I don't see any force that could open up the parachute.
  7. Jan 3, 2009 #6

    Ranger Mike

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    solar wind..solar sails been discussed since 1962..far as i remember.
    everything is " moving" in this universe...it has been conjedtured that solar wind could propel space vehicle if properly designed.
  8. Jan 6, 2009 #7
    What force do the "solar winds" push with? What exactly are solar "winds"? Photons?
  9. Jan 6, 2009 #8


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    The Solar Wind is the stream of charged particles form the sun (electrons and protons) arriving at earth.
    A solar sail actually uses the pressure of the photons from the sun - not the solar wind.
  10. Jan 6, 2009 #9
    A Solar Sail/Solar Parachute could use the drag produced by moving towards the sun by "catching" photons with a big non-reflective parachute. However, the problem is that the sail would need to be hundreds, or even thousands of square kilometers to be effective. Also, it probably wound never "deploy" like a regular parachute because the pressure on any given point of the sail/chute wouldn't be enough to move it. A solar sail/solar parachute counts on the cumulative pressure on the entire sail over a long period of time (months at least to build any meaningful momentum, probably years to reach functional travel speed), so it would need to start in place.

    Note that probably more effective than an physical sail/chute would be a really big (again thousands of kilometers) electromagnetic or electrostatic field. If it were negatively charged then it would create drag as it encountered the positively charged protons released by the sun.
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