Spacecraft Life Support System Design Guidelines for Human Exploration of the Moon and Mars

Project Constellation incorporates a modular spiral design process initially intended to enable human travel to the moon with the Crew Exploration Vehicle (CEV), including accommodations for landing and long-term surface habitation. The lunar activities will serve as a test bed for subsequent destinations such as Mars, near-Earth asteroids, or the outer planets; therefore, the requirements for meeting future expectations should also be anticipated to the extent possible in the early development spirals. To help advance this comprehensive goal, a process for conducting a ‘system-of-systems’ analysis was established. Individual mission elements were characterized for each distinct stage of travel to and from Low Earth Orbit (LEO), the moon, and Mars, including relevant surface operations. Next, considering fundamental human inputs and outputs as baseline design drivers, shared clusters of spacecraft life support system (LSS) requirements were identified as a function of respective mission elements. Resultant life support processes were then grouped in terms of being common or unique to each element, and anticipated mission durations were factored in to begin analysis of a complementary integrated system design. As a result of this preliminary study, LSS design guidelines are provided for developing a modular ‘system of life support systems’ to help establish overall mission architecture requirements for human exploration of our solar system.