Application of solar electric propulsion to comet and asteroid rendezvous and docking /CARD/ missions with sample return.

Summary of a feasibility study of CARD mission/system concepts for comet Encke and asteroid Eros missions in the late 1970s. A common planetary vehicle employing a modular SEP (solar electric propulsion) system and a direct rendezvous/docking mode with a staged science/sampling module appears feasible based on 1973 technology. The SEP system utilizes 3.5-kW, 3500-sec Isp mercury ion thrusters and rollout solar arrays sized at 36 (Encke) and 13 (Eros) kW based on the Titan III family launch vehicles. Science payloads, sampling concepts, and supporting spacecraft subsystems are defined. Problem areas are identified, and programmatic considerations are discussed.