Thursday, June 18, 2015

Spaceships of the Merchanters and Stationers Universe #2

Spaceships of the Merchanters And Stationers universe use spin gravity or thrust gravity, depending on their function.


Riders are ships designed to be carried on larger ships. They use thrust gravity while in space - their decks are laid out perpendicular to the direction of thrust - but land on their sides. Cabins are designed to rotate on landing, with the entrances engaging different corridors than in flight configuaration.

Landers and Shuttles

Landers and shuttles are designed for short flights in space, and do not need to worry about internal gravity. Consequently, they are laid out parallel to the direction of thrust, like airplanes. Many cargo landers carry inflatable seats in the decking to carry a variable number of passengers.

Asteroid Mining Craft

Asteroid mining craft spend all of their time in space, and use thrust gravity if any. Miners spend considerable time in zero-G, and must spend equivalent long periods exercising at higher G on station to repair damage to their bones. Thus most asteroid mining craft have two or three sets of crew who alternate using the craft.


Starships - Jump capable craft - operate from station to station, never landing for long periods. Thus they use spin gravity while in flight. Each ship has a rotating cylinder which houses all habitable areas, and spins on it’s long axis, giving a moderate gravity outward while inertial - that is, while coasting between boosts. While boosting, crew remain in their crash couches or beds, moving only during brief inertial periods to change shifts.

Starships are constructed with a ventral keel running the length of the craft, and usually side and dorsal keels as well. All turrets and airlocks are built into these keels for strength. An armored shell is built around the rotating cylinder - all ships are at least Armor factor 1 to deflect dust and debris, and protect from near misses - and over the cargo hold(s). The main engines and Jump Vanes are built near the end of the ship. At the nose are the docking equipment - probe, cargo doors, and personnel tubes and locks into the habitable areas.

When in station, starships lie nose into the rim, dorsal keel out, parallel to the inside of the rim. They lock into the immensely strong side walls of the station rim and support structures, with the personnel tube leading down to the station floor, while the cargo doors mate up above, and the station’s docking gantries load the ship.

In dock, the rotating section is locked down, and the ship uses the station’s rotation for spin gravity, so most of the ring is sideways or upside down, and mostly unusable. The ship’s crew thus must stay on station in hotels called “sleep-overs”, and while not helping with the loading, are off duty.


  1. I've always had a hard time visualizing docking at station in the Cherryh-verse. I thought ships went in nose-first with their tails sticking out (there's a scene at Downbelow Station where someone travels from ship to ship via a service shuttle that seems to pass from engine stack to engine stack - implying that the ships' sterns are sticking out into space.

    But if the station is rotating, then the bows of the ships would come up through the floor of the concourse as the rim of the station is "down". Yet the descriptions of dockside have the floor curving upwards in each direction (makes sense as the rim is "down" and you can see the curve of the deck) with the ships docked through what is essentially the "side" wall of the station.

    I think it works if you imagine the station as a barrel rotating on the axis running through the top and bottom of the barrel. The various decks of the station are smaller and smaller barrels nestled inside each other until you come to the zero-g core. The ships dock through the end of the barrel, and all docks are in a strip running around the outer edge of that end.

    Does that make sense?

  2. Hi Dave!

    Yes, that's exactly the conclusion I came to, though your analogy is better! The only way they can use station "gravity" is if they line up around the inside lip of the barrel, nose in and tail out! :D