Sunday, November 29, 2020

When you're tired of the isolation

We earlier had ruled out that Hohmanns will meet... ever. Unless they find a meeting table...

Consider the Earthling, once inbound to Venus, whom Hop David has stuck in his 0.8 of a year cycler. Five runs of that is four years for us Earthlings! For Venereans it is exactly twice as bad: they have to go through it all again to get home. If they follow The Rules, that is.

An A synod inbound passing Venus, and a post-A outbound from Venus, both, during C synod some four earth years later, will next enter STL5 - 71 degrees behind Terra anyway, but at least headed in the ecliptic direction. Both become there "A inbound". Here is one last Hohmann return to Venus' orbit. But not to Venus. The erstwhile A synod inbound was Earth based; if it doesn't return to Earth on C, its second four-year whip 'round is destined first for SVL3. Its counterpart post-A outbound is blasting through SVL3 on its way, yes, to Earth. But let's talk four years after that: E synod.

The old A inbound, now cruising out in the STL5 basin, could run one more 4/5-year half-synod to maybe cross paths with the post-E outbound... but that's all that crosses, paths. The A Train's passengers may be fed up with the isolation. Such might board a shuttle to skip back a few degrees of halo orbit, to join the next post-A Hohmann to Venus, thence Earth that way. Again these guys won't meet the post-E outbound; the post-E is too close to Earth. They get to Earth themselves also later but desperate people get desperate.

Luckily for all those in STL5 (and STL4), they are basins. Once there they can skate along and find their own Hohmanns down to Venus. It took 280 m/s to get from STL2 (approximately) to the Earth / Venus Hohmann; it will take exactly that delta-V to get to another Solar orbit shared with Earth. For a halo orbit like STL5 coming from behind, less, I think.

STL5, I think, will have merchants. Some are making their last score before returning to Earth in the good company of that next outbound. Some are just shuttle-pilots. With enough presence in STL5, or in SVL4-5 for that matter, I suspect Hohmann longtermers will choose just to stay there not over E synod but at C. Those will need to wait that bit longer of course.

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