Speaker
Description
Sun-Earth L2 (SEL2) halo orbits are crucial for deep-space exploration, offering continuous Earth visibility, a stable thermal environment, and favorable observational conditions. While numerous past and planned missions have targeted SEL2, a comprehensive parametric analysis of transfer trajectories remains absent in the literature. This study addresses this gap by systematically characterizing SEL2 transfer trajectories using the Circular Restricted Three-Body Problem (CR3BP) framework. The proposed parametric framework provides a robust foundation for the preliminary design of future SEL2 missions, enabling efficient trajectory selection and optimization.
This work presents a detailed mapping of trajectory design trade-offs, considering energy cost, transfer time, and operational constraints. It also provides a parametric description of SEL2 halo orbits, analyzing stability properties, eclipse exposure, Earth visibility, telecommunication and power constraints, and station-keeping requirements. Additionally, mission end-of-life (EoL) strategies are explored, offering insights into feasible disposal approaches.
Given that transfer trajectory cost is a primary concern, special attention is given to identifying low-cost transfer options within a one-year transfer period. By leveraging hyperbolic manifold dynamics, various transfer strategies from Earth parking orbits are systematically investigated, considering departures from both Low Earth Orbit (LEO) and Geostationary Transfer Orbit (GTO). Three primary injection methods are analyzed: direct insertion from LEO/GTO pericenter at an altitude of 200 km, an approach utilizing a Poincaré map for optimized transfers, and insertion from GTO.
By offering a systematic approach to trajectory design, this work supports ongoing and upcoming deep-space exploration initiatives. It provides a comprehensive baseline for the preliminary design of missions targeting SEL2 halo orbits and has been applied to the preliminary trajectory design of the REMEC (ESA) mission.