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Re: Can you push a spacecraft with light?

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On Friday, January 22, 2016 at 7:35:10 AM UTC-8, Sam Wormley wrote:
> On 1/21/16 10:15 PM, Peter Riedt wrote:
> >
> > If photons had mass, maybe.
> >
> 
>    From the quantum mechanical perspective:
> 
>      1. photons are emitted (by charged particles)
>      2. photons propagate at c
>      3. photons are absorbed (by charged particles)
> 
>    Photon Momentum
>      p = hν/c = h/λ
> 
>    Photon Energy
>      E = hν = hc/λ
> 
> 
>    Can you push a spacecraft with light? YES
>  > https://www.youtube.com/watch?v=oIuvIDhcs8E
> 
>  > What if you could power a ship using sunlight instead of wind? Well
>  > in space, you can! Solar sails or light sails are pushed with light
>  > from the sun. Photons provide a kick when they reflect off the sail
>  > pushing the sail like an air molecule in the wind pushes a sailboat.
>  > Find out how a solar sail works and about the future of this
>  > technology!

In fact, you can even move an asteroid or a comet with light...

http://www.space.com/19905-dangerous-asteroid-deflection-paint.html

http://www.wired.com/2013/02/painting-asteroids/

http://www.forbes.com/sites/alexknapp/2012/10/28/an-earth-killing-asteroid-could-be-deflected-with-paintballs/#304be351d789

\Paul A

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Thread

Can you push a spacecraft with light? Sam Wormley <swormley1@gmail.com> - 2016-01-21 16:28 -0600
  Re: Can you push a spacecraft with light? "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-01-21 14:40 -0800
    Re: Can you push a spacecraft with light? benj <none@gmail.com> - 2016-01-21 20:45 -0500
    Re: Can you push a spacecraft with light? "hanson" <hanson@quick.net> - 2016-01-21 21:35 -0800
  Re: Can you push a spacecraft with light? jimp@specsol.spam.sux.com - 2016-01-21 23:25 +0000
    Re: Can you push a spacecraft with light? Sylvia Else <sylvia@not.at.this.address> - 2016-01-22 16:30 +1100
      Re: Can you push a spacecraft with light? jimp@specsol.spam.sux.com - 2016-01-22 05:46 +0000
      Re: Can you push a spacecraft with light? benj <none@gmail.com> - 2016-01-22 07:05 -0500
        Re: Can you push a spacecraft with light? Sylvia Else <sylvia@not.at.this.address> - 2016-01-22 23:28 +1100
    Re: Can you push a spacecraft with light? Mahipal <mahipal7638@gmail.com> - 2016-01-22 14:25 -0800
    Re: Can you push a spacecraft with light? Sam Wormley <swormley1@gmail.com> - 2016-01-23 10:03 -0600
      Re: Can you push a spacecraft with light? jimp@specsol.spam.sux.com - 2016-01-23 19:08 +0000
  Re: Can you push a spacecraft with light? Peter Riedt <riedt1@yahoo.co.uk> - 2016-01-21 20:15 -0800
    Re: Can you push a spacecraft with light? benj <none@gmail.com> - 2016-01-22 07:02 -0500
    Re: Can you push a spacecraft with light? Sam Wormley <swormley1@gmail.com> - 2016-01-22 09:35 -0600
      Re: Can you push a spacecraft with light? pnalsing@gmail.com - 2016-01-22 13:19 -0800
  Re: Can you push a spacecraft with light? "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-01-22 12:57 -0800
    Re: Can you push a spacecraft with light? "hanson" <hanson@quick.net> - 2016-01-22 14:45 -0800

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