LIGHT SAILS:

Discussion in 'Astronomy, Exobiology, & Cosmology' started by paddoboy, Jan 26, 2015.

  1. billvon Valued Senior Member

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    21,635
    I think it was more recent than that, and was driven by that patent (and several others) that were clearly unworkable. The latest revision of that section was 2012, but I know it was in there in 2001 - so I suspect some time between 2001 and 1979.

    http://www.uspto.gov/web/offices/pac/mpep/s608.html
     
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  3. nebel

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    Russ & Bill, I should not have made an argument by appealing to superior authority, the patent examiners. ( think Albert in Switzerland) The US patent office will not entertain applications in Perpetual Motion or "Reactionless, internal propulsion devices", but sometimes they just throw up their hands and grant patents that are disguised , and even to apparatuses and methods that are designed to prove that it does NOT work.
    as to post 94, the rotational sail would exert a force perpendicular to the incoming radiation, as explained in post 31. and
    how about using the extensive sail surface doing double duty, to glean the very sparse matter in space and accelerate it in an Ion drive engine?, as proposed somewhere?
     
    Last edited: Jan 30, 2015
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  5. paddoboy Valued Senior Member

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    Thanks OnlyMe...Wonderfully and genuinely put and accepted

    Please Register or Log in to view the hidden image!

     
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  7. Kittamaru Ashes to ashes, dust to dust. Adieu, Sciforums. Valued Senior Member

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    For what it's worth - my reaction was not to your posts.
     
  8. paddoboy Valued Senior Member

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    I knew that. Thanks.
     
  9. Kittamaru Ashes to ashes, dust to dust. Adieu, Sciforums. Valued Senior Member

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    No problem - just wanted to make sure in case there was any actual confusion (as opposed to the intentional confusion/misdirection that a certain member seemed intent on injecting into this thread)
     
  10. dumbest man on earth Real Eyes Realize Real Lies Valued Senior Member

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    So...Post #71 following Post #70 - no one should expect that it had to do with Post #70?
    Sorry, Kittamaru, but you failed to mention which Post it was referring to...

    Kittamaru, if you cannot PROVE "intentional confusion/misdirection" by ANY member, then you should not be making such accusations...

    Incidentally, what was your Post #71 a "reaction" to?
     
  11. nebel

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    OnlyMe: I am using your 2 step absorption / delayed emission explanation, 9#970 to add credence to the assertion, that planets are rotational solar sails. They absorb photons in the daytime and emit the gained energy during the evening, night, pushing into the orbit direction . In the cool morning, when meteors are frequent, your are facing into the orbit direction, the lowest energy state during the planet's daily cycle.
     
  12. Russ_Watters Not a Trump supporter... Valued Senior Member

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    Let's assume you are correct: why don't you try calculating just how much acceleration that can provide to a planet?
     
  13. OnlyMe Valued Senior Member

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    I think it has been mentioned, in less colorful terms.., but all together what you are talking about, compared to the earth's inertial momentum and the earth-sun gravitational interaction, is like a knat on and elephants butt!
     
  14. OnlyMe Valued Senior Member

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    Sorry, but I guess that depends on whether the knat bites a sensitive spot on the....
     
  15. nebel

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    mouse milk. It could over billions of years though offset the effect of incoming matter on the leading, morningside, and if you made a large, rotating, radiation absorbing, light-skinned cylinder, perhaps tensioned by centrifugal force, you could get translational movement. and
    think rotating comet heads.
     
  16. origin Heading towards oblivion Valued Senior Member

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    You are misquoting the law. The law states that an object in motion will move in the same direction and the same speed unless acted upon by a force. So for the earth the sun is continually imposing a gravitational force on the earth and the direction of the earth is continually changing due to this force. Simple, at least if you have had some exposure to science.

    A Light sail could not be launched from earth, or even escape an orbit around earth. If you place a light sail on a trajectory away from the sun it will gain speed due to the radiative pressure from the sun.

    You need to learn the most very basic science before you try to tackle anything remotely complicated.
     
  17. nebel

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    Russ & OnlyMe, perhaps a "Yarkovsky Effect" search would help to put numbers on the force generated, perhaps used to keep an object in a Lagrangian point, and synergistically generating artificial gravity?
     
    Last edited: Feb 1, 2015
  18. nebel

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    origin, a light pressure driven object, at the right distance, can escape the Sun's gravity, but you would have to call it a Solar mini-sail; miniaturization at it's best.
    search "Poynting-Robertson Effect"
     
  19. Russ_Watters Not a Trump supporter... Valued Senior Member

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    Again: why not stop guessing and handwaving and instead calculate it?
     
  20. nebel

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    R_W : No need to guess: it has been calculated. incoming solar constant "radiation pressure x effective area". Assuming that the Earth heat household is in equilibrium, daytime absorbed energy is re-radiated by morning, absorbed energy is going into translational forces.
    The nitty gritty calculation have been done for bodies of all sizes. Size matters. Are you THAT interested in arithmetic?
    A small enough "solar sail"* will reach escape velocity. believe it or not, it is the mass to surface ratio.
     
    Last edited: Feb 1, 2015
  21. Russ_Watters Not a Trump supporter... Valued Senior Member

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    Where? Show me.
    Yes, because if you haven't done the math, then you are just guessing.
     
  22. nebel

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    No guesswork, the math, the physics is done: google "total radiation pressure on the Earth" follow the links; the references in # 114; # 115, "radiation pressure on satel-lites" (and heavies), " radiation pressure effects on asteroids" it is all done.
    What is your motive in harping on the minute?, for small minds? If the devil is in the details, are you playing the role of the exorcist?
     
  23. Russ_Watters Not a Trump supporter... Valued Senior Member

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    I will not do the work for you: show me the numbers and the actual links where you go them, to prove you arent just guessing. This should be easy if you've already done it and by not doing it, you imply very strongly that you are in fact just guessing.
    Proving that the math supports your claim is not minutae, it is everything in science. Otherwise, you are just fantasizing and may not be able to separate your fantasies from reality. I'm trying to help you think an learn.
     

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