Research on Earth-Moon transfer by using a large amplitude Lyapunov orbit

A method is described for constructing a new type of low energy transfer trajectory from the Earth to the Moon by utilizing a large amplitude Lyapunov orbit which is tangential to the lunar orbit. In order to find the specific Lyapunov orbit, a simple numerical method is investigated by analyzing the states in the Poincaré map. After achieving the patch of the lunar orbit and the large amplitude Lyapunov orbit, the Earth-Moon transfer problem can be transformed into that of transferring to the Lyapunov orbit from the Earth. In order to guarantee the spacecraft can escape from the low Earth orbit (LEO) tangentially, the periapsis map is introduced to determine the spacecraft's initial states when calculating the stable manifolds, and then Earth-Moon transfer is accomplished from these initial states. Numerical simulations demonstrate that compared with the classical Hohmann transfer, this new transfer strategy needs approximately 100 m/s less fuel consumption and provides a new way of thinking for low energy Earth-Moon transfer.