Quincey Forder wrote:

What size could it be?

I think it could be whatever size makes sense economically. Agriculture has a few constraints: you need to provide sunlight, water and nutrients to the plants. They do not need much gravity, and can be grown very densely and efficiently as hydroponic farming. Racks of transparent boxes with drip-irrigation goes a long way. Vat-farming is even more efficient. But it still requires sunlight (or at least fusion-powered light sources, if it is far out in the solar system) to feed algae in growth tanks that are then either directly turned to food or turned into nutrients for the meat vats. Growing real plants in soil is much less efficient (not to mention animals!) - but will of course appeal to people who can afford "real" food (think of how much people currently spend on organic food today, and then scale it up to a much wealthier future population) So if the habitat is merely supplying other local habitats with food, it would likely be fairly small and dense - a green-glittering labyrinth of sunny hydroponics and high-efficiency life support systems that take in raw materials (asteroid regolith, ammonia-rich ice, waste from other habitats) and turn them into nutrient raw materials. If it aims at the export industry for "real" food it will tend to be larger, but presumably not enormous: for plants gravity does not have to be high, and animal meat might actually become tougher if reared in normal gravity. I would imagine a classic Bernal sphere or cylinder a few kilometres across would be more than enough. There would maybe be a high-efficiency section with agriscrapers producing raw nutrients, and perhaps some residential areas for local workers and people living the "rural" life. Of course, after the Fall the economy for expensive plants and animals tanked almost everywhere (except maybe around Mars), so the above habitat might have started to decline in interesting ways.

Classic O'Neil cylinders tend to be large because they need enough of a radius that, when spun, they create gravity close to 1g. If you remove that constraint, you can make it much smaller. If you do want gravity, the cylinder will be kilometers across, and likely tens of kilometers long, with alternating transparent and opaque panels to permit daylight and space to walk. I believe both of the first habitats in Schismatrix are O'Neill cylinders. (Completely unrelated, just realized if you take an O'Neill cylinder, make its surface super dense and spun that close to c, you could take your home back in time. Great if you missed The Big Game or something.)

Quincey Forder wrote:

Cool! Do you a scan of the pages? I have a text only PDF

You could purchase a PDF [url=http://e23.sjgames.com/item.html?id=SJG30-6704]from the publisher[/url] for $9.99us.

Glad to help. That's a good book. Lots of ideas in there. Well with nanotech I suspect the hull around the breech will grow after sensing the damage until the hole is sealed. The nanites would strip a layer off the surrounding hull to use as building materials. So they answer is they wouldn't have to do anything. Emergency mechanisms shouldn't require anyone's input, they just deploy. Or you could have drones sitting on the hull drop a modular patch plate over the hole and weld it in place. Harder though since presumably atmosphere is escaping out. Of course I'm a biologist not an engineer.

Yep, exactly what I was thinking. Got it on the edit. Sometimes I rush things since I'm at work in the middle of an experiment.

Getting a habitat that size 'functioning' is a huge undertaking, comparable to the difficulty of building it in the first place. I'm not sure how the habitat has spun down like it has, but it takes a lot of energy to get it spinning up again. A fusion generator that has shut down normally takes a very large 'jumpstart', plus complex conditions, high-quality fuel, and the functioning of a very complex machine. I don't even know how you'd rebuild a hundred cube kilometers of lost atmosphere. If this habitat is in as poor condition as you're describing, and they're only there to do a search, I would revive the minimal number of subsystems required to do that search and leave the rest to rot.

How could the attackers manage to halt the station's spin? It would surely be quite a difficult and time consuming process to arrest that kind of momentum. And equally challenging to get it going again. I'm thinking on the order of weeks or months, even by transhuman tech standards. And the bigger you make the station, the more unlikely it seems (there might even be someone here nerdy enough to illustrate the physics of such a colossal feat, but it ain't me). Maybe you could hand-wave something about the station falling into a strange situation gravity-wise, or have it spinning off-axis (which might actually present more challenges than zero-g). It would have to be some major hand-waving though. Big things in space seem to want to spin.