Previously on rec.arts.sf.tv.babylon5.moderated, Vince M Hudd said:   
      
   > > Why is a Lagrange Point a "natural crossroads"? What is it about one of   
   > > these points that make it better for such use than merely someplace in   
   > > orbit?  For that matter, what IS a Lagrange Point? I've heard the name,   
   > > but never understood what it is or why it's a good thing.   
   >    
   > A Lagrange Point is a point in space relative to an orbital pair - such as   
   > Earth and Moon, or Sun and Earth - where the various mutual forces cancel   
   > each other out such that a much smaller object can remain there unaffected.   
   >    
   > I think there are five for each pair:   
      
   Five?  I had only previously heard of two, the ones that don't seem to   
   make sense leading and trailing the smaller body (Moon, in this case).   
      
   > One sits between the two (closer to the smaller of the pair than the   
   > larger). This one is probably the easiest to understand, because the biggest   
   > factor is the two gravitational pulls. This is the one Andrew was referring   
   > to as EML1 - Earth/Moon Lagrange Point 1; being directly between the two   
   > bodies (obviously closer to the Moon than Earth) it's a logical place to put   
   > a 'stepping stone' between Earth and Moon.    
      
   Ok, that's an obvious.  It's a "midway" point, being mid-way on the   
   gravitational inclines.   
      
   > Another sits *beyond* the smaller of the two bodies. Here, anything in the   
   > Langrange point is orbiting the larger object on the same orbital period as   
   > the smaller one - and the gravitational pull acting on it is the combined   
   > pull of both of them, which is counter-acting the centripetal force brought   
   > about by its orbital speed.   
      
   That makes sense too, essentially a geo-stationary orbit in-line around   
   the pair.   
      
   > Another sits on the same line, but on the other side of the larger object,   
   > and the same principal applies as with the second one.    
      
   Ok.   
      
   > The other two sit at points along the orbital path of the smaller object,   
   > one ahead of it, and one following it. IIRC, their positions effectively   
   > form two equalateral triangles with the centres of the two bodies, and I'm   
   > not quite sure I understand the physics of these two. If I try to make sense   
   > of one, the other makes my head explode because it just seems wrong, so I   
   > just trust that the men in the white coats know what they're talking about.   
      
   Which men in the white coats?  I can think of two types... :)   
      
   --    
   Jeffrey Kaplan                                         www.gordol.org   
   Double ROT13 encoded for your protection   
      
   Peter's Top 100 Things I'd Do If I Ever Became An Evil Overlord, #110.   
   I will not employ devious schemes that involve the hero's party   
   getting into my inner sanctum before the trap is sprung.   
   --- SBBSecho 2.12-Win32   
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