Solar sail parking in restricted three-body systems

Stationary solutions to the restricted three-body problem for solar sail spacecraft in the Earth-sun and Earth-moon systems are investigated. It is found that the usual five Lagrange points are extended to a continuum of new artificial points that form level surfaces parameterized by the sail mass per unit area. Analytic expressions for the sail mass per unit area and the sail attitude required for these stationary solutions are obtained and the stability of the solutions examined. It is found that although in general the solutions are unstable, a simple closed-loop control scheme may be developed to ensure asymptotic stability.