Comparative Analysis of Current NASA Human Mars Mission Architectures

The human Mars Mission architectures recently under study are compared. The evolution of mission modes utilizing indigenous resources for propellant production is described. A historical summary of human Mars architecture design is given as a way of introducing some of the challenges inherent to mission planning. A Mars architecture option based on minimum development costs and risks, rather than minimized mass in low Earth orbit, is presented. A multiyearMars vehicle set, characterized by chemical propulsion transfer stages (with aerocapture forMars orbit capture) is described. It is maintained that, for the current Mars Design Reference Mission, the development of more costly advanced propulsion technologies (such as nuclear thermal propulsion, nuclear electric propulsion, or solar electric propulsion) can be considered as later, evolutionarysteps from this initial, less costly, all-chemical approach. Emphasis is given to the minimization of new technology development programs and the associated impacts on total Mars mission costs. Analysis is based on the availability of an 80-metric-tonpayload-class launch vehicle. An important ground rule is the preclusion of on-orbit assembly, allowing only for the joining of complete and fully fueled transfer stages in orbit.