Low-Thrust Trajectory Design for Rendezvous Missions to Jupiter and Saturn Using Nuclear Electric Propulsion

Nuclear Propulsion presents a promising alternative for deep space missions, especially for rendezvous missions to outer planets and beyond. It is primarily classified into Nuclear Electric Propulsion (NEP) and Nuclear Thermal Propulsion (NTP). NEP and NTP both offer greater payload capacity and achieve significantly higher specific impulse than traditional chemical propulsion. While NTP uses high thrust impulsive trajectories like chemical propulsion, NEP uses low thrust trajectories with constant acceleration which helps in achieving high velocities over time. This analysis builds upon the prior work which included a preliminary trajectory design for a Jupiter rendezvous mission. The results demonstrated that a 40 kW NEP spacecraft with a payload of 2.3 metric tons (mT) takes 9.13 years and 8.49 years to reach Jupiter using NASA’s Evolutionary Xenon Thruster (NEXT) ion and XR-5 Hall thrusters, respectively. While these initial results provide valuable insights into NEP capabilities, further analysis is needed to refine the trajectory design model. This paper increases the fidelity of the trajectory design model and incorporates additional mission concepts for NEP rendezvous missions to the gas giants - Jupiter and Saturn. It presents a mission and vehicle analysis using low thrust trajectories and different types of electric thrusters, such as NEXT, XR-5 Hall, Magnetoplasmadynamic (MPD) and Advanced Electric Propulsion System (AEPS) Hall thrusters. Further, the performance of the NEP missions is compared to that of NTP missions using an equivalent payload mass to ensure a fair and balanced assessment. This comparative analysis serves as part of a broader study to determine the solution space for outer planetary missions using NEP. Additional mission scenarios are planned for a comprehensive evaluation.