Interplanetary transfers using solar sails and electric propulsion

Abstract

From the beginning of space travel, numerous types of propulsion systems, alternative to the original chemical engine, have been proposed. Today the low-thrust engines are a reality and the Deep Space 1 mission launched by NASA in October 1998 demonstrated this concept in practice. Besides, the solar pressure gives the possibility of using another propulsion system of low-thrust, the solar sail. The use of a solar sail is a wonderful prospect for interplanetary travel because no propellant mass is required, but only the weight of the sail. In this work we will use interplanetary transfers with low-thrust, of the power limited (PL) type, for the electric propulsion system. We will consider the following options of direct transfers: Earth-Saturn, Earth-Uranus, Earth-Neptune and Earth-Pluto. Analyzing the advantage and disadvantage of using several electric propulsion system (solar, nuclear, and radioisotope). Besides, the solar sails are applied to the schemes of transfers considering the advantage or disadvantage of using plane or composed sails. An analysis of the possible advantage or disadvantage of the solar sail compared to the electric propulsion system will also be made. In all those studies we will use the Pontriagyn principle of variational calculus to obtain minimum-time trajectories through the indirect optimization method.