Linguofreak
Well-known member
I've been trying to put together a TransX plan for a Venus cycler. Basically, the synodic period between Earth and Venus is about 8/5 of a year, with the result that there are 5 Hohmann windows to Venus over an 8 year period, after which the same sequence of Hohmann windows repeats with the planets in (almost) the same positions as the previous cycle (shifted by about 1 degree).
Meanwhile, the period of an Earth/Venus Hohmann orbit is almost exactly 4/5 of a year (meaning the transfer takes roughly 2/5 of a year), which, combined with the above, means that a spacecraft on a Hohmann transfer to Venus that does a flyby instead of stopping just needs to do a gravity-assist (rather than a burn) to arrange to re-encounter Earth 8 years after launch, where it can gravity-assist into the next iteration of the Hohmann window it launched into, and from there it can go on swinging through an endless EVEVEVEVEV... slingshot series.
The only problem is that it's rather difficult use TransX to put such a plan together, but it's the only tool I know of that will handle the number of orbits needed. Everything else I can find (including a few items on Orbithangar as well as NASA's Trajectory Browser) handles only two or so revolutions around the sun if it handles multiple orbits at all. Just going through one iteration of a cycler (from launch or flyby at a given planet to the next flyby of that planet) takes ten orbits (8 years, at 4/5 of a year per orbit). Does anybody know of a trajectory planning tool that can handle this?
Meanwhile, the period of an Earth/Venus Hohmann orbit is almost exactly 4/5 of a year (meaning the transfer takes roughly 2/5 of a year), which, combined with the above, means that a spacecraft on a Hohmann transfer to Venus that does a flyby instead of stopping just needs to do a gravity-assist (rather than a burn) to arrange to re-encounter Earth 8 years after launch, where it can gravity-assist into the next iteration of the Hohmann window it launched into, and from there it can go on swinging through an endless EVEVEVEVEV... slingshot series.
The only problem is that it's rather difficult use TransX to put such a plan together, but it's the only tool I know of that will handle the number of orbits needed. Everything else I can find (including a few items on Orbithangar as well as NASA's Trajectory Browser) handles only two or so revolutions around the sun if it handles multiple orbits at all. Just going through one iteration of a cycler (from launch or flyby at a given planet to the next flyby of that planet) takes ten orbits (8 years, at 4/5 of a year per orbit). Does anybody know of a trajectory planning tool that can handle this?
