Optimal low-thrust out-of-ecliptic trajectories

Low-thrust trajectories may offer a better means of entering out-of-ecliptic trajectories than ballistic maneuvers. Previous efforts examined families of trajectories resulting from the optimization of ballistic maneuvers with the expressed intent of reaching a given height above the ecliptic plane. This displacement serves to reduce the noise due to dust in the local zodiacal cloud. Low-thrust trajectories offer a more efficient means of reaching required out-of ecliptic orbits and also offer the possibility of increased observation time. The low-thrust trajectories developed in this paper were found by using an iterative genetic algorithm approach followed by a local optimizer. The paper examines the feasibility of using different thrust systems based on current and near term capabilities.