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>> All of this is such a distant problem, it seems way too soon to even speculate on. We're hundreds of years away from the logistics of transporting thousands of humans to Mars being a practical consideration. As such, the mere mention of Starship feels utterly anachronistic.

This is not hundreds of years away, it is the goal of SpaceX. They are not just building Starship, they are building a factory with a target production rate of one ship per day. The goal is not to send a few ships to Mars, but an armada. With so many ships around, and a window to Mars about every 2 years it makes sense to start building infrastructure like this with them while they're waiting.

Yes, Elon is a bit... ambitious. And I question whether he is actually serious about it all. But if he is, this is happening over the next 50 years.

> They are not just building Starship, they are building a factory with a target production rate of one ship per day.

So SpaceX is going to build a Starship, which has to travel tens of millions of miles through the unforgiving frontier that is space, at one a day? Boeing manages to build a 737 in about nine days and those land on Earth every few hours of operation for maintenance and checkups.

Those two vehicles have very different flight profiles, so comparing them is of limited value, but yes, that is the plan.

>you still need to change your velocity in the exact same amount on both ends of the trip

You usually need to change your velocity more than that.

Cycler orbits are more constrained in their start/end dates, so there are fewer free parameters to "tune" for lower propellant consumption. Generally a cycler with a 4 month transit time will need slightly more delta-v vs. sending a ship on a regular old transfer orbit with an identical 4 month transit time.

This is because when designing a cycler orbit it's usually necessary to shift a few days ahead/behind the optimum dates for a 4 month transfer, in order to efficiently "stitch together" with the previous/next orbit cycle.

> We're hundreds of years away from the logistics of transporting thousands of humans to Mars being a practical consideration.

With decades of experience with the ISS and Starship's first orbital flight on the docket, why would this be hundreds of years away? Consider the technical progress we've made in launch vehicles in the last 15 years alone. Are there really any technical problems on the path to a mars cycler that could give us centuries worth of trouble? Or are you simply suggesting that the demand won't be there?

Way more distant if you consider how poor would be life on Mars.

Unless you think of it as a giant experiment to travel outside the Solar system, further down the road, when the Sun will eat up the entire solar system. In that case, though, you'll need a larger cycler with a much different shuttle for you to board/unboard it...