Investigating the Design Space for Solar Sail Trajectories in the Earth- Moon System

Solar sailing is an enabling technology for many mission applications. One potential application is the use of a sail as a communications relay for a base at the lunar south pole. A survey of the design space for a solar sail spacecraft that orbits in view of the lunar south pole at all times demonstrates that trajectory options are available for sails with characteristic acceleration values of 1.3 mm/s 2 or higher. Although the current sail technology is presently not at this level, this survey reveals the minimum acceleration values that are required for sail technology to facilitate the lunar south pole application. This information is also useful for potential hybrid solar-sail-low-thrust designs. Other critical metrics for mission design and trajectory selection are also examined, such as body torques that are required to articulate the vehicle orientation, sail pitch angles throughout the orbit, and trajectory characteristics that would impact the design of the lunar base. This analysis and the techniques that support it supply an understanding of the design space for solar sails and their trajectories in the Earth-Moon system.