Optimization of the Return Trajectories from the Moon for Delivering Soil to a Specified Region on the Earth’s Surface

Abstract—The construction of the trajectories for spacecraft return from the Moon to the Earth for delivering lunar soil to the polygon specified by the corresponding geographical coordinates (φ_Πλ_Π) considered in this paper. A special technique for this purpose is developed. The spacecraft departs from the polar near-Moon orbit with a height of 100 km. The analysis of the energy characteristics of the spacecraft return trajectories is carried out for the year 2024. The most favorable dates in terms of the minimum value of acceleration impulse are selected. The satellite flight from the Moon to the Earth is simulated taking account of the perturbations of gravitational fields of the Earth, the Moon, and the Sun in the geocentric geoequatorial nonrotating coordinate system.