A Deep-Space Free Port

[Korto]

Well, I'm starting a new Tjapukai story (sorry, you won't be seeing it here. I have vague thoughts one day of trying to get them published), and it's set on a space station, at a way-point solar system, about 200 au out from the sun (which is convenient for interstellar passers-by, not having to waste time going deep into the system).
The station was originally built as a small stop-over, a chance for ships to re-fuel, and travellers to stretch their legs in some gravity. It also was a trading post for the colony in-system. It was built as one of those wheel-and-spoke stations, spinning for artificial gravity.
Since then it's become independent, and it's grown. Quite literally. The station has had parts added to it, more living space, commercial space, and the supporting infrastructure; much of this (most, really) has been quite ad hoc, old ships and even cargo containers fixed into place, new hatches cut and joined on, jury-rigged in with varying aptitude. It's become an important trading hub, particularly for those who may have "misplaced" their paperwork.

Let's see--Oxygen is supplied in two ways, mechanical/chemical cleaning, and algae vats (which also supply a large portion of the food). They get power from in-system, and also buy and sell power with ships (mainly sell, but they'll act as market makers if needed).
The station is now quite large and labyrinthine. It's easy to get lost in it.

So, I'm opening this up for input. Any thoughts about possible problems, how things may work there, etc. The story's just started, so there's lots of room for ideas.

[Lord Revan]

I'd say unless it's important to the story keep the technology as much of "black box" as you get away with without seeming like you're intentionally hiding things, if you don't explain how things work (or exlpain only in very broad strokes) there's less changes of things ending up wrong.

[bilateralrope]

Keeping the axis of rotation in the same place while making all those jury-rigged additions would be difficult. What kinds of problems would that cause ?

Did they enlarge the station by attaching parts to the bottom or sides of the station (define down as being away from the axis of rotation) ?
If they went down far enough, the lower rooms would have a significantly higher gravity in them. Maybe someone has a shaft where they lower people they don't like on a rope down it to torture them.

[Simon_Jester]

Well, I'm starting a new Tjapukai story (sorry, you won't be seeing it here. I have vague thoughts one day of trying to get them published), and it's set on a space station, at a way-point solar system, about 200 au out from the sun (which is convenient for interstellar passers-by, not having to waste time going deep into the system).

The station was originally built as a small stop-over, a chance for ships to re-fuel, and travellers to stretch their legs in some gravity. It also was a trading post for the colony in-system. It was built as one of those wheel-and-spoke stations, spinning for artificial gravity.
Since then it's become independent, and it's grown. Quite literally. The station has had parts added to it, more living space, commercial space, and the supporting infrastructure; much of this (most, really) has been quite ad hoc, old ships and even cargo containers fixed into place, new hatches cut and joined on, jury-rigged in with varying aptitude. It's become an important trading hub, particularly for those who may have "misplaced" their paperwork.

Let's see--Oxygen is supplied in two ways, mechanical/chemical cleaning, and algae vats (which also supply a large portion of the food). They get power from in-system, and also buy and sell power with ships (mainly sell, but they'll act as market makers if needed).
The station is now quite large and labyrinthine. It's easy to get lost in it.

So, I'm opening this up for input. Any thoughts about possible problems, how things may work there, etc. The story's just started, so there's lots of room for ideas.

1) Are your ships sublight or FTL? How fast is interplanetary travel? If drive technology is advanced enough, and if there's no such thing as 'jump points,' there isn't much purpose in a refreshing stop being that far out in deep space. From some directions it'll be "on your way," but from other directions you have to maneuver around the inner system of the nearby star to get to it. If propulsion is very advanced in sublight space, or if FTL drives can easily bring ships into the sidereal universe close to a planet (a la Star Wars), then there is no need whatsoever for ships to make 'pit stops' in deep space except under unusual conditions.

Make sure your setting supports the economic logic of the station's existence in that particular time and place. Otherwise, you need to move or transform the station so that it fits into the setting.

2) As another specific example, from the way you describe "for travellers to stretch their legs in some gravity," it implies that interstellar spacecraft don't have artificial gravity, be it spin-gravity, acceleration-gravity, or otherwise. Is that supported by the rest of your setting?

3) As noted, adding lots of improvisational additions to a space station that uses centrifugal gravity is tricky. As long as the individual additions are small relative to the overall station it shouldn't be a problem, but eventually the resulting weight imbalances could make it difficult if not impossible to actually control the station's rotation. A lot depends on how effectively the station government can zone and control construction.

[Jub]

Rather than one big station that has been added to, I think it would make sense to have a collection of smaller stations, old ships, containers made livable, etc. The fact is, very few people are going to want ramshackle mods added to the place they work and live. This is especially true when said place is also the one place you can trust not to leak or fall apart.

This gives the same ramshackle effect, but in the form of a junk flotilla rather than one giant station.

[Batman]

For a refueling station that far outsystem to make sense they practically HAVE to have FTL (also, he mentions interstellar travelers). Also, rotational gravity implies that (at least at the time of construction) they had no artificial gravity which means no acceleration compensation. Even a constant boost ship would take weeks to get there from the inner system at tolerable g levels. Also, in interstellar terms it's still relatively close to the solar system (technically I think it's still within the system) indicating their ships simply don't have the legs for STL interstellar.

As for why so far out, a lot of settings with FTL nevertheless require you to get out of the system's 'gravity well' before you can jump (a lot of Asimov's writing for example) though Korto will have to answer that.

[bilateralrope]

I'm thinking that the setting has one of the following:
- Jump points, with the station being near one.
- FTL is rather precise, the cost of coming out on one side of the system or the other is negligible, but you have to enter/exit FTL that far out from the star. So everyone chooses to come out near the station.

[Simon_Jester]

It was said that this station is mostly there to service ships that aren't stopping at the nearby star system. It's the equivalent of a freeway rest stop several miles from the nearest city, in other words- only loosely affiliated with the city, and far more interested in the ebb and flow of traffic along the highway than in customers from the city proper.

Especially since, as Batman points out, if people here are using spin gravity and don't have some kind of magic inertial compensator, the odds are that their ships cannot accelerate above, oh, two or three gravities. In which case reaching the station 200 AU from the parent star would take ludicrously long periods of time.

However, there are a lot of imponderables here that we can't answer without firmer information on sublight and superlight drive performance, what the nearby star system is like, and so on. The key point isn't to draw any single conclusion. It's to make sure that the station makes economic sense in context- that people would actually want to stop there, specifically, in sufficient numbers to permit the station to thrive.

[Jub]

Even with faster drives and less need for refueling, you can still make the station profitable by having it operate as a duty-free zone for goods coming into/out of the system. If your treaty says that a system's sphere of influence extends out to 200au a station sitting just outside that limit could make sense as a hub for trade.

[Simon_Jester]

I'd like to add that I like the idea that you have a station surrounded by a collection of new construction. This is preferable to a single station being constantly modified in ramshackle ways. That latter suggests a lack of the kind of coordination, planning, and high standards of technical safety required to keep the station as a thing that won't die. Basically, ramshackle doesn't work well in the context of space stations and space travel, because the environment is so unforgiving that mechanical breakdowns tend to result in instant death unless the tools and skills to fix the problem are readily available.

A well maintained space station may well be okay if a meteor punctures the hull. But it will survive because all the major internal bulkheads are airtight, the blast doors seal automatically, the patching equipment is well maintained, the patching crews are well trained, and the outer hull is made of plating that's of a standard that can accomodate the patch.

If the outer hull plating has aged out of spec because nobody ever takes the time to do maintenance, the patching crews are part-timers, the equipment is not maintained because it hasn't been used in years, the blast doors' automatic mechanisms have been bypassed because someone found it annoying that they'd automatically close due to false alarms once in a while, and some of the internal bulkheads have undocumented holes cut in them for cable runs and "ramshackle" water piping...

Everybody dies.

...

As to the more general questions of location and economics... There are lots of ways for the station to make sense- it's simply that there are also lots of ways for it to not make sense.

So the first step in plotting the story is to examine the underlying premise and make sure it isn't a second order idiot plot, in which the station has no logical reason whatsoever for existing. If the station does not have a logical reason to exist as described in its present location, then either the background needs to be edited to make sense of it, or the station should be relocated to a more sensible location.

[Korto]

Let's go through this post by post...

I'd say unless it's important to the story keep the technology as much of "black box" as you get away with without seeming like you're intentionally hiding things, if you don't explain how things work (or exlpain only in very broad strokes) there's less changes of things ending up wrong.

Agreed, and I try to keep it vague and broad-strokes in the stories, but I also like to work it out privately as much as I can. It may help me keep it more consistent.

Keeping the axis of rotation in the same place while making all those jury-rigged additions would be difficult. What kinds of problems would that cause ?
Did they enlarge the station by attaching parts to the bottom or sides of the station (define down as being away from the axis of rotation) ?
If they went down far enough, the lower rooms would have a significantly higher gravity in them. Maybe someone has a shaft where they lower people they don't like on a rope down it to torture them.

Anyone adding is required to get an engineer's report, but even so in the introduction part the protagonist is advising his new crew member to "Aways keep your ship-suit and helmet on.". I don't know what specific problems it would cause (that's part of why it's here), but I could imagine things tearing loose.
I'm thinking that due to the increased forces in adding something to the bottom, the cheapest places to add would be nearer the hub, but those who can afford it would prefer around the 1g line, so most additions would be between the spokes, and out to the sides.

1) Are your ships sublight or FTL? How fast is interplanetary travel?

2) The way you describe "for travellers to stretch their legs in some gravity," it implies that interstellar spacecraft don't have artificial gravity, be it spin-gravity, acceleration-gravity, or otherwise. Is that supported by the rest of your setting?

3) As noted, adding lots of improvisational additions to a space station that uses centrifugal gravity is tricky. As long as the individual additions are small relative to the overall station it shouldn't be a problem, but eventually the resulting weight imbalances could make it difficult if not impossible to actually control the station's rotation. A lot depends on how effectively the station government can zone and control construction.

1) Interstellar jump drive. If operated within recommended safe parameters, the longest jump is 6 ly at a time, to around 200-300 au out from a system ("micro jumps" can get in closer, to within 20 au), and including recommended preparation and recovery time makes for an average speed of 1 ly / 3 days. For technical reasons, it's safest to jump to a system than into the interstellar void.
This results in ships hopping from system to system, with preferred routes due to conveniently placed stars.

Interplanetary momentum drive--a special high physics field lowers the ship's mass in relation to the universe, causing it to go faster to conserve momentum. It can go up to 0.1c before interactions between the field and relativity get too difficult to control, however no acceleration is felt from this drive so it can't create artificial gravity.

2) I may have to back-check, as at one point I was thinking of some kind of magical artifical gravity, but I've been reading a lot of Schlock and I've decided it would just cause too many problems for me. Basically, it either is supported, or it will be.

3) The station government can exert some control, I'm thinking it's something like a town run by a council of pirates. Self-interested, callous, and corrupt, but not stupid. Also not reluctant to throw their weight around if necessary.

Rather than one big station that has been added to, I think it would make sense to have a collection of smaller stations, old ships, containers made livable, etc.

Not a bad idea. I was already thinking a lot of business between ships gets conducted off-base, to avoid loading and unloading fees. I do however also like the idea of this large complex held together with baling wire and spray-sealant. Might have both, with the main base, but a few satellite ones.


I'm not entirely sure if there is an actual colony in this system, or if there ever was. If there isn't one, then that's one less power that the base would have to worry about, but it makes their food and air supply more interesting. Of course, I could always take Revan's advice and just not mention those details.

[Simon_Jester]

Anyone adding is required to get an engineer's report, but even so in the introduction part the protagonist is advising his new crew member to "Aways keep your ship-suit and helmet on.". I don't know what specific problems it would cause (that's part of why it's here), but I could imagine things tearing loose.

I'm thinking that due to the increased forces in adding something to the bottom, the cheapest places to add would be nearer the hub, but those who can afford it would prefer around the 1g line, so most additions would be between the spokes, and out to the sides.

The logical place to add stuff to the station is to simply build the additions onto the 'walls' of the ring, extending the ring station into a 'tube' that still rotates around the same axle. Think about a pickup truck with two tires on the rear axle. If the station's initial volume is one of the tires, the easiest place to put additions would be in the second tire. That way, the radius of rotation is constant, the addition doesn't add more mechanical stress to the station (or if it does, it can be compensated for by also extending the structural bracing), and people moving into the extension from other parts of the station don't have to experience a gravity change.

1) Are your ships sublight or FTL? How fast is interplanetary travel?

1) Interstellar jump drive. If operated within recommended safe parameters, the longest jump is 6 ly at a time, to around 200-300 au out from a system ("micro jumps" can get in closer, to within 20 au), and including recommended preparation and recovery time makes for an average speed of 1 ly / 3 days. For technical reasons, it's safest to jump to a system than into the interstellar void.
This results in ships hopping from system to system, with preferred routes due to conveniently placed stars.

Is a point way out in the Kuiper Belt considered "in a system" for purposes of emerging from a jump? That sounds a bit odd. But maybe I'm just thinking like someone who lives in the Goldilocks Zone; a liquid helium creature might know very well what the difference is.

Interplanetary momentum drive--a special high physics field lowers the ship's mass in relation to the universe, causing it to go faster to conserve momentum. It can go up to 0.1c before interactions between the field and relativity get too difficult to control, however no acceleration is felt from this drive so it can't create artificial gravity.

Clever. The field exerts uniform acceleration on everything within it, so no gravity is experienced- and arbitrarily reducing the inertia of matter might have interestingly stressful effects on the hull (and crew) if you tried to generate spin gravity. I'd have to think about that.

2) The way you describe "for travellers to stretch their legs in some gravity," it implies that interstellar spacecraft don't have artificial gravity, be it spin-gravity, acceleration-gravity, or otherwise. Is that supported by the rest of your setting?

2) I may have to back-check, as at one point I was thinking of some kind of magical artifical gravity, but I've been reading a lot of Schlock and I've decided it would just cause too many problems for me. Basically, it either is supported, or it will be.

Gotcha. This in turn suggests that ships' ability to accelerate without use of their magical inertia-manipulation drive is very limited. On the other hand, as noted, speed and ability to reach top speed are very high when the inertia-reduction drive is active. Likewise, a ship can drastically alter velocity while underway by turning off or dialing down the drive. Note that 200 astronomical units is roughly one light-day, giving you a sense of how fast ships could cover the distance.

3) As noted, adding lots of improvisational additions to a space station that uses centrifugal gravity is tricky. As long as the individual additions are small relative to the overall station it shouldn't be a problem, but eventually the resulting weight imbalances could make it difficult if not impossible to actually control the station's rotation. A lot depends on how effectively the station government can zone and control construction.

3) The station government can exert some control, I'm thinking it's something like a town run by a council of pirates. Self-interested, callous, and corrupt, but not stupid. Also not reluctant to throw their weight around if necessary.

Thaaat's a problem.

See, a callous, corrupt, self-interested oligarchical clique can do a pretty good job maintaining basic law and order. But for things like "having reliable building codes" and "keeping up on safety inspections," they don't work very well, among other things because every oligarch has a cousin who thinks they should be exempt from the building codes or that safety inspections are bullshit.

What it comes down to is that for a space station to survive, you need a kind of "herd immunity" to technology breaking down. This immunity is reached by ensuring that almost everything is so well maintained, efficient, and redundantly backed up that no single failure of any piece of technology poses a threat of causing a chain of further failures that kills everyone. It doesn't take a lot of corruption or callous indifference to the welfare of the little people before this herd immunity breaks down, in my opinion.

Of course, having the whole station physically explode or fall apart in the last scenes of the novel due to all the bad maintenance might be exactly the way you want your novel to end. So much for space libertarianism.

Rather than one big station that has been added to, I think it would make sense to have a collection of smaller stations, old ships, containers made livable, etc.

Not a bad idea. I was already thinking a lot of business between ships gets conducted off-base, to avoid loading and unloading fees. I do however also like the idea of this large complex held together with baling wire and spray-sealant. Might have both, with the main base, but a few satellite ones.

It may well be that the original station is well maintained, if nothing else because the factors of the major merchant firms, the local smuggler lords, and so on, want a secure place to live that has air to breathe more than 99% of the time. But then there's the spacegoing shantytown that's sprung up around it, which honors few or no regulations other than traffic controls, in the form of "move your hab out of our inbound traffic lane or we will lase you until your eyes sizzle."

I'm not entirely sure if there is an actual colony in this system, or if there ever was. If there isn't one, then that's one less power that the base would have to worry about, but it makes their food and air supply more interesting. Of course, I could always take Revan's advice and just not mention those details.

Well, it takes ten days to get there from the inner system, and quite possibly less than that to get there from the nearest habitable planet in another system, assuming that it doesn't take ten days to get into the outer system before a ship can jump to FTL...