Libration point trajectory design

Orbits about the Sun–Earth L1 and L2 libration points have become very popular for space physics and astrophysics missions. Due to the hyperbolicity of the region of phase space where these orbits are found, they are difficult to compute and analyze. The invariant manifold structure provided by dynamical systems theory has been useful to compute transfer trajectories between orbits. These methods are very promising and require further development. This systematic approach is a great improvement from the difficult and labor-intensive numerical search methods currently popular in the astrodynamics community for studying these orbits. The geometric constraints and mission critical issues are discussed to give the numerical dynamical systems community some insight into the practical considerations and important problems of interest to the space mission designers. It is hoped that this communication will lead to more fruitful exchanges between the two communities.