Use of Orbit-to-Orbit Shuttles for Hyperbolic Rendezvous with Returning Planetary Spacecraft

Abstract

An Earth-return mode for interplanetary spacecraft via hyperbolic rendezvous is described. In this mode an orbit-to-orbit shuttle leaves a circular Earth orbit, performs a rendezvous with a returning interplanetary spacecraft approaching Earth on a hyperbolic trajectory, docks, and performs desired transfers, and deboosts back into a circular Earth orbit while the spacecraft continues on its hyperbolic path. The initial mass in Earth orbit required for a rendezvous system utilizing chemical or nuclear propulsion compares favorably with the initial masses in Earth orbit chargeable to transport of a retrobraking Earth-return system to a target planet and back. The maneuver also has considerable merit as a backup and rescue system for any planetary mission even when not suitable as a primary recovery mode.