Sun–Earth $$L_{1}$$ L 1 and $$L_{2}$$ L 2 to Moon transfers exploiting natural dynamics

Abstract

KeywordsCoupled circular resriied tree-body problem, libra ion poin , weak cap ure, lunar impai, lunar cap ure Abstract is paper examines the design of transfers from the Sun-Earth libration orbits, at the L1 and L2 points, towards the Moon using natural dynamics in order to assess the feasibility of future disposal or lifetime extension operations. With an eye to the probably small quantity of propellant left when its operational life has ended, the spacecraft leaves the libration point orbit on an unstable invariant manifold to bring itself closer to the Earth and Moon. e total trajeory is modeled in the coupled circular restried three-body problem, and some preliminary study of the use of solar radiation pressure is also provided. e concept of survivability and event maps is introduced to obtain suitable conditions that can be targeted such that the spacecraft impas, or is weakly captured by, the Moon. Weak capture at the Moon is studied by method of these maps. Some results for planar Lyapunov orbits at L1 and L2 are given, as well as some results for the operational orbit of SOHO.

End-of-life disposal concepts for Libration Point Orbit and Highly Elliptical Orbit missions

“…A study was undertaken to create a map of conditions near the L 2 libration point of the Earth-Moon system which can be reached from the Sun-Earth system and lead to a longer duration quasi-periodic orbit about the Moon or an impact on the lunar surface [9]. The resulting set of initial conditions about the Earth-Moon L 2 libration point, their corresponding orbit lifetime, and their category of decay (i.e., Moon impact or lunar capture or exit via libration points) serves as the basis of designing transfers from SunEarth libration point orbit towards the Moon.…”

“…Further details on the design strategy of disposal trajectories towards a Moon impact are given in Ref. 9. In the following section the case scenarios of Herschel, Soho ad Gaia are presented.…”