End-to-end optimization of conceptual roundtrip mars missions with exact precession elliptical parking orbits

Roundtrip missions to the surface of Mars that involve elliptical parking orbits can be designed to have tangential arrival and departure maneuvers at Mars to minimize propellant expenditure. For Mars stays of sufficient length, a discrete set of parking orbits exists which allows for natural orbital precession to satisfy the strict geometric requirements for this elliptical parking orbit operational strategy. The design space for this strategy is investigated in the context of an end-to-end trajectory optimization. Illustrated with 2030 and 2033 mission opportunities, it is shown that variable interplanetary event dates coupled with coplanar ascent and descent provide a continuum of feasible solutions, allowing for access to any landing site latitude on Mars.