XPost: sci.space.moderated, sci.space.shuttle   
   From: mikecombs@nospam.com_chg_nospam_2_ti   
      
   "Chuck Stewart"  wrote in message   
   news:pan.2004.10.16.06.01.20.929903@gmx.co.uk...   
   > On Fri, 15 Oct 2004 14:54:36 -0500, Jon Berndt wrote:   
   >   
   > > Nowhere is mention made that this particle beam causes any "equal and   
   > > opposite" action at the particle-beam source. If this near-Earth station   
   is   
   > > blasting a particle beam into space that causes a spaceship to   
   accelerate   
   > > (momentum transfer) to "tens of thousands" of mph ... what is the source   
   > > doing to maintain position or orbital velocity? Am I missing something?   
   >   
   > Just handwave in electrodynamic tethers and you can devise a   
   > truly Rube Goldbergian propulsion scheme.   
      
   Bob Forward has the same problem with his laser-propelled sail.  His laser   
   array was orbiting Mercury in a plane perpendicular to the path of the   
   receding sail.  When the lasers fired, the orbit was displaced slightly from   
   the plane cutting through the center of gravity of Mercury, but the array   
   continued orbiting and didn't leave.   
      
   See no reason one couldn't do the same from Earth.   
      
   --   
      
      
   Regards,   
   Mike Combs   
   ----------------------------------------------------------------------   
   Member of the National Non-sequitur Society.  We may not make   
   much sense, but we do like pizza.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)