From: mha@TheWorld.com   
      
   I'm working on a story that mentions a freighter, the Millie Gee, that   
   cycles regularly between Luna and Deimos.   
      
   The Millie Gee uses solar power from large arrays to power a   
   vasimr engine whose ejection mass is lunar water.  She never touches   
   down, is reached by tugs/landers from both destinations.  (Her cargo   
   for her first trip out included a tug for the Deimos end of her   
   schedule.)  She follows an elliptical orbit between her two ports; but   
   has options for other travel if the need arises.   
      
   I think my solar powered Millie Gee would serve better for local   
   travel inside the asteroid belt, than solar sail propulsion, because   
   (assuming appropriate design) she could accelerate in any direction at   
   any time.  Which a solar sail cannot do.   
      
   Why "tug" in story space, rather than "shuttle"?  Because in story   
   environment, "shuttle" has bad connotations.   
      
   Cheers -- Martha Adams   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)