Also, Mind the Gap

spin-stop: A stop on a non-axial habitat (or occasionally starship) internal transit line for access to a spin gravity area.

While in many cases the most convenient way to allow access to a gravity wheel or rotating segment within an otherwise non-rotating habitat is an axial transit line (or, in small examples, floatway), this is not universally the case.

In such examples, the spin-stop, a loop of track parallel to the spin section, serves to provide access. As the name suggests, rather than the train or transpod stopping at the station, as it would elsewhere, it simply comes to a stop relative to the spin, having entered the loop in synchronization with the rotating station. That is to say, while at a spin-stop, the vehicle is actually continuing to move at the tangential velocity of the spin section; typically, dozens to hundreds of miles per hour.

This is imperceptible to those boarding or departing the vehicle, of course, since the relative motion is the relevant motion. However, passengers unfamiliar with spin-stops should be aware that in many designs the vehicle cannot hold its departure for errant passengers, and the consequence of not standing clear of the closing doors are inevitably rather messy.

– A Star Traveler’s Dictionary

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  1. Avatar for avatar avatar says:

    I was thinking of Ceres in The Expanse with this one. Sure, there are lots of technical difficulties involved with trying to spin up an asteroid, but at least you don’t have to worry about being trapped between subway car and gravity wheel for a 40 mph grating…

  2. Another result of the eldraeic ethos of “we put the damn warning signs there for a reason,” I suppose. The hazard reminds me of a paternoster, as well.

  3. Avatar for avatar avatar says:

    Yeah, there is a certain “Seriously, we put up signs, we made an announcement, at what point did this fail to become clear to you?” about it.

    …now I have paternostalgia.

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