Mars Sample Return mission studies leading to a reduced-risk dual-lander mission using solar electric propulsion

A two-phased classical systems engineering approach was applied to a broad trade space of options for the Mars Sample Return Mission in 2011 or 2013. The studies and the detailed designs were heavily driven by three factors: the probability of mission success, planetary protection requirements, and the constraints associated with launch windows and capabilities. In the first phase, several architecture options were assessed and a preferred candidate making use of solar electric propulsion (SEP) was selected for more detailed development in the second phase. SEP mission durations were shown to be heavily dependent on thrust/mass ratios in a step-wise fashion driven by synodic dependencies. SEP missions were shown to provide the ability to significantly reduce mission risk by enabling paralleling of critical mission elements such as the entire landed asset chain. A low risk surface operation and sample handling strategy was combined with heritage-based rendezvous and dock, active decontamination of the return vehicle, and direct passive Earth entry, descent, and landing. This work was performed for the Jet Propulsion Laboratory, California Institute of Technology, sponsored by the National Aeronautics and Space Administration.