Yup, someone thought of it. That man's name? Buzz Aldrin. https://buzzaldrin.com/space-vision/rocket_science/aldrin-mars-cycler/ https://buzzaldrin.com/space-v

Yup, someone thought of it. That man's name? Buzz Aldrin. https://buzzaldrin.com/space-vision/rocket_science/aldrin-mars-cycler/ https://buzzaldrin.com/space-vision/rocket_science/aldrin-ma... https://web.archive.org/web/20101102073607if_/http://buzzaldrin.com/files/pdf/1985.10.28.ALDRIN_SAIC_PAPER.Cyclic_Trajectory_Concepts_0.pdf https://web.archive.org/web/20101102073607if_/http://buzzald... It is indeed more efficient to perform the usual Hohmann transfer, but the advantage of the Aldrin Cycler concept is you can accelerate a large vehicle once and then 'amortize' that over multiple trips.