On-orbit assembly of Mars transfer vehicles

Developmental efforts conducted under NASA-Marshall aegis toward on-orbit assembly for manned Mars mission transfer vehicles (MTV) are presented. The MTV types considered encompass those with cryogenic/aerobraking propulsion, all-cryogenic propulsion, nuclear-thermal propulsion (NTP), nuclear-electric propulsion (NEP), and solar-electric propulsion (SEP). Attention is given to NTP, NEP, and SEP MTVs, in light of the requirements posed by the assembly environment and assembly platform designs. Much important design-related information is being derived from the Long Duration Exposure Facility.