Cryogenics and the human exploration of Mars

Current studies within NASA involve extending the human exploration of space from low earth orbit into the solar system, with the first human exploration of Mars proposed in 2014. The key cryogenic technology areas to be addressed in human Mars missions are long-term propellant storage, cryogenic refrigeration, cryogenic liquefaction, and zero gravity fluid management. Passive technologies such as advanced multilayer insulation (MLI) concepts, vapor-cooled shields (VCS), and catalytic converters will be combined with the development of active coolers (cryogenic refrigerators). The integration of passive and active technologies will form a hybrid system optimized to minimize the launch mass while preserving the cryogenic propellants. This paper will present a brief overview of the proposed Mars reference mission and the concomitant cryogenic fluid management technology, focusing on active cooling technology.