Solar Electric Propulsion Vehicle Design Study for Cargo Transfer to Earth-Moon L1

ABSTRACTA design study for a cargo transfer vehicle using solar electric propulsion was performed for NASA’s Revolu-tionary Aerospace Systems Conceptsprogram. Targetedfor 2016, the solar electric propulsion (SEP) transfervehicle is required to deliver a propellant supply module with a mass ofapproximately 36 metric tons fromLow Earth Orbit to the first Earth-Moon libration point (LL1) within 270 days. Following an examination ofpropulsion and power technology options, a SEP transfer vehicle design was selected that incorporated large-area (~2700 m 2 ) thin film solar arrays and a clustered engine configuration of eight 50 kW gridded ionthrusters mountedonanarticulatedboom. Refinement of the SEP vehicle designwasperformediteratively toproperly estimate the required xenon propellant load for the out-bound orbit transfer. The SEP vehicle per-formance, including the xenon propellant estimation, was verified via the SNAP trajectory code. Further ef-fortsare underway to extendthissystem model to otherorbit transfer missions.INTRODUCTION