Gravity-assist trajectories to Jupiter using nuclear electric propulsion

This paper examines optimal low-thrust gravity-assist trajectories to Jupiter using nuclear electric propulsion. Three different Venus-Earth Gravity Assist (VEGA) types are presented and compared to other gravity-assist trajectories using combinations of Earth, Venus, and Mars. Families of solutions for a given gravity-assist combination are differentiated by the approximate transfer resonance or number of heliocentric revolutions between flybys and by the flyby types. Trajectories that minimize initial injection energy by using low resonance transfers or additional heliocentric revolutions on the first leg of the trajectory offer the most delivered mass given sufficient flight time. Trajectory families that use only Earth gravity assists offer the most delivered mass at most flight times examined, and are available frequently with little variation in performance. However, at least one of the VEGA trajectory types is among the top performers at all of the flight times considered.