Flow Tube

Author: Tianjiang Shuo Website: https://cislunarspace.cn

Definition

The tubular structure formed by invariant manifolds of small-amplitude libration point periodic orbits in phase space. Transit orbits inside the flow tube enable low-energy transfers between Earth and Moon regions but cannot directly reach low-Earth or low-lunar orbits. When the Lyapunov orbit amplitude increases beyond a threshold, the tubular structure degenerates into open sheets.

Application Value

Lyapunov orbits are the most fundamental periodic orbit type near libration points, and their invariant manifolds provide natural pathways for low-energy transfers.

References

• 郑越和赵敏 2023, §0, §1.2