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   rec.arts.sf.science      Real and speculative aspects of SF scien      45,986 messages   

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   Message 45,671 of 45,986   
   eripe to Bob Jenkins   
   Re: earth space elevator, moon, tilt   
   17 Sep 19 18:22:03   
   
   From: eripe.dk@gmail.com   
      
   On Tuesday, September 17, 2019 at 10:12:38 PM UTC+7, Bob Jenkins wrote:   
   > On Monday, September 16, 2019 at 5:03:11 PM UTC-7, eripe wrote:   
   >    
   > > The force from the moon is tiny compared to the self correcting force to   
   the rotating plane. If the station is 1° off that plane it will be pulled   
   back by a force of sin(1)= 1,7% of its mass.    
   > > The moon can only make it wobble a widdle.   
   >    
   > What assures that the rotating plane of the elevator remains the plane of   
   the equator?   
      
   Short answer: The moment of inertia.   
      
   Another way of thinking about it is that the plane is where the system has the   
   lowest amount of mechanical energy (kinetic + potential), so that's where it   
   wants to be.   
   That said, if a oscillation (wobble) begins, you have to watch it and have   
   means to dampen it out. Without resistance to movement in space it will   
   oscillate forever, and if the cause is in sync with the natural frequency of   
   the system it will continue to    
   grow.   
      
   The amount of force you mentioned first is however so small that you should be   
   able to counter it by opening a window for a few seconds.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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