Concept for 2033 Crewed Mars Orbital Mission with Venus Flyby

The 2033 Mars launch period provides a unique opportunity for a round-trip mission with a total flight time of only 1.6 years. A concept is presented to perform a crewed Mars orbital mission in 2033 that would minimize development and mission risk by using conventional hypergolic in-space propulsion stages with a common design. The Mars mission vehicle would include a Mars transit habitat, an Orion spacecraft, and chemical propulsion stages. It would be launched by a combination of Space Launch System and commercial rockets to be aggregated in high Earth orbit or at the Lunar Gateway. The crew would launch to the mission vehicle in Orion as the final element in the assembly. After transit to Mars, the crew would spend about 30 days in a high Mars orbit and then return to Earth via a Venus flyby and gravity assist. A sunshade would be deployed for thermal control of the mission vehicle inside 1 astronomical unit. The crew would return directly to Earth in the Orion crew module, with the transit habitat being expended. The 2033 mission would not be a "one-off" but could be a pathfinder for crew transport for landing missions to follow, perhaps starting as early as 2037.