Target selection and transfer trajectories design for exploring asteroid mission

Technique of target selection and profiles of transfer trajectory for Chinese asteroid exploring mission are studied systemically. A complete set of approaches to selecting mission targets and designing the transfer trajectory is proposed. First, when selecting a target for mission, some factors regarded as the scientific motivations are discussed. Then, when analyzing the accessibility of targets, instead of the classical strategy, the multiple gravity-assist strategy is provided. The suitable and possible targets, taking into account scientific value and technically feasible, are obtained via selection and estimation. When designing the transfer trajectory for exploring asteroid mission, an approach to selecting gravity-assist celestial body is proposed. Finally, according to the mission constraints, the trajectory profile with 2-years Delta V-EGA for exploring asteroid is presented. Through analyzing the trajectory profile, unexpected result that the trajectory would pass by two main-belts asteroids is found. So, the original proposal is extended to the multiple flybys mission. It adds the scientific return for asteroid mission.