Trajectory design for a lunar mission to map, and return samples from, the South Pole-Aitken Basin

Samples returned from the lunar far-side South Pole-Aitken (SPA) Basin would be valuable for Solar System origins studies. Trajectories are described that could map the SPA Basin for selecting a good site for landing, followed by an ascent and return of samples from the site to the Earth. The paper describes the transfer trajectories from Earth to the Moon, the polar lunar mapping orbit, a larger equatorial orbit for two small comsats to provide communications for far side operations, the lunar landing, the ascent from the Moon, and the return of the samples to the Earth.