Trajectory design for awaiting comets on invariant manifolds with optimal control

Abstract

Comet exploration missions represented by the Comet Interceptor mission have attracted our attention to unravel the origin of our solar system. However, it is difficult to know the details of orbital data about long period comets (LPCs) until their approach. Additionally, the amount of fuel consumption by the current intercept approach depends on the intersection points of cometary orbits with the ecliptic plane. To address these challenges, designing low-energy transfer trajectories suitable for the observation of LPCs is necessary. This paper introduces a novel approach by utilizing invariant manifold structures in the Sun-Earth circular restricted three-body problem for comet missions with multiple probes. As candidates for departure orbits, periodic orbits and quasi-periodic orbits are considered. Based on the optimal control theory, low-thrust trajectories to improve mission efficiency for enlarging the reachable domain of multiple probes are designed by leveraging invariant manifolds. The trajectories guided by invariant manifolds and optimal control theory facilitate formation flying, multi-point observations, and explorations of unknown comets by multiple probes.