Trajectory options for solar polar region observation mission

A study on the post-HINODE Solar Observation Mission has been started by members in the solar physics community. One candidate of the mission targets on the observation of the solar polar region from the orbit largely inclined with the ecliptic plane. In order to achieve this severe mission target, possible trajectory sequences are investigated considering the application of various trajectory manipulation techniques. Three major trajectory options are listed up to achieve the mission objective. The first option, "SEP option", is characterized by the usage of solar electric propulsion (SEP) combined with the earth gravity assists. The other options are characterized by the usage of planetary gravity assists, and SEP is not used in these options. They are named "Jupiter option" and "Venus option" respectively. The comparison among the trajectory options is discussed in the paper, not only from the aspect of the orbital mechanics, but also from the aspects of the spacecraft design and operation.