Mission design for Human Outer Planet Exploration (HOPE) using a magnetoplasma spacecraft

To send humans beyond Mars, a Human Outer Planet Exploration (HOPE) mission has been studied for new spacecraft concepts and technologies. In this paper, an interplanetary trajectory and a preliminary spacecraft design are presented for the HOPE visit to Callisto, one of Jupiter's moons. To design a round-trip trajectory for the mission, the characteristics of the spacecraft and its trajectories are analyzed. A detailed optimization approach is formulated to utilize a Variable Specific Impulse Magnetoplasma Rocket (VASIMR) engine with capabilities of variable specific impulse, variable engine efficiency, and engine on–off control. It is mainly illustrated that a 30 MW powered spacecraft can make the mission possible in a 5-year round trip constraint around the year 2045. Trajectories with different power and reactor options are also discussed. The results obtained in this study can be used for formulating an overall concept for the mission.