LunarHalo:

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   Initial conditions for a Sail halo in the Earth-Moon system.
   The x and y motion would then be x0*cos(wS*t) and y0*sin(wS*t).
   The z coordinate is the displacement out of the plane.
   The pitch angle, is not entered, is the optimal value to maximize the 
   z coordinate, i.e. atan(1/sqrt(2))
   If no outputs are give it will plot the trajectory.

   Since version 7.
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   Form:
   [r0,xL,wS,Omega,rMoon] = LunarHalo( accel, L, theta, muM, muE )
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   Inputs
   ------
   accel   (1,1)    Sail characteristic acceleration (km/s2)
   L       (1,1)    Index to collinear Lagrange point (1, 2, 3)
   theta   (1,1)    Sail pitch angle (optional)
   muM     (1,1)    Moon gravitational parameter (optional)
   muE     (1,1)    Earth gravitational parameter (optional)

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   Outputs
   -------
   r0     (3,1)     Displacements from the Lagrange point (km)
   xL     (1,1)     Linear distance to Lagrange point from corotating origin
   wS     (1,1)     Dimensioned lunar synodic orbit rate
   Omega  (1,1)     Rate of frame rotation
   rMoon  (1,1)     Average lunar distance for nondimensionalization
   U      (3,1)     Partial derivatives of potential

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   References: Colin R. McInnes, "Solar Sailing: Technology, Dynamics and Mission  
               Applications", Springer Praxis, London, 1999.
               Colin McInnes, "Solar Sail Trajectories at the Lunar L2
               Lagrange Point", J. Spacecraft, Vol. 30, No. 6, 1993.
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Children:

Common: Database/Constant
Common: Graphics/Plot3D
SC: Ephem/LagrangePointsL1ToL5
SC: Visualization/PlotPlanet