On the Sun-driven long-lasting temporary capture in the Earth-Moon system

In the context of the renewed interest in the lunar and cislunar environment, the understanding of the rich dynamics identifying the Earth-Moon system is key for designing operational trajectories, ensuring a sustainable exploitation but also to better characterizing the natural bodies that can interact with Earth, Moon and the artificial bodies therein operating. In this work, we investigate a specific class of orbits, that exhibit a long-lasting temporary capture behavior, meaning that they can have a continuous negative geocentric energy for interval of times of the order of years. The motivation lies in the understanding of the dynamical evolution found by looking for potential minimoons derived from lunar ejecta. It turns out that the main driver is the third-body perturbation exerted by the Sun, not the Moon. By investigating specific sets of three-dimensional hyperbolic periodic orbits in the Circular Restricted Three-Body Problem and the behavior of the corresponding stable invariant manifold, it is possible to define specific sets of initial conditions leading to such long-lasting behavior, distinguishing between geocentric prograde and retrograde motion. Finally, the geometry of the trajectories is analyzed to see the interaction with the Moon’s environment.