Possible trajectories for Electric Solar Wind Sail validation

The aim of this paper is the analysis of a potential mission scenario that could be used to perform an in-situ test of the Electric Solar Wind Sail. Such an advanced propulsive system works only outside the Earth's magnetosphere, so a translunar mission (where the spacecraft is supposed to be inserted as a secondary "piggyback" payload) is hypothesized, in which at least a part of the spacecraft trajectory is around or beyond the Moon's orbit. The analysis of possible selenocentric trajectories is conducted with a three-dimensional generalization of the classical patched conic approximation. In particular, two cases are considered: a closed selenocentric orbit, and a Moon flyby that inserts the spacecraft on a post-flyby geocentric orbit with at least some branches outside the Earth's magnetosphere.