[Space] What is the 'Gaia' type of garden worlds like? ('Habitability 9').

[Frost]

Originally Posted by Daigoro

I think that completely depends on your tech assumptions. Given limitless cheap fusion energy for powering massive skyfreighters, they might be more economically priced than slower water transport.

True to a point but remember that the same the same tech could be used in marine aplications this will leave you with much the same trade offs as exist today. Based upon the speculations about the planetary environment those long coastlines are probably going to be the decisive factor. Although I wouldn't rule out both.

Originally Posted by Daigoro

This might be more of a political question. I could imagine a Chinese-style central government telling all the settlers where to settle after mapping out a detailed 100-year economic plan, then making the transport work around that.

Probably not, the rationale for distributing you settlements is unaffected by the way you are organising the colony. First of all you don't want to put all your eggs in one basket. Two or more sites reduce the impact of human or natural disasters. Secondly you are going to be using resources drawn from a fairly wide area anyway, giving your mines and plantations permanent populations of workers makes sense. Placing these will be a matter of economics with transport as one of the major factors.

Originally Posted by Daigoro

Well, this is a possible Gaia planet, so there might be pleasant afternoon showers every day to refill the city's reservoirs.

Like the shipping example above it is a good point but natural reservoirs will still be cheaper. Now once you have a decent surplus built up this may be less of an issue but by then many of your major cities will already be established.

[Daigoro]

Originally Posted by Frost

True to a point but remember that the same the same tech could be used in marine aplications this will leave you with much the same trade offs as exist today. Based upon the speculations about the planetary environment those long coastlines are probably going to be the decisive factor. Although I wouldn't rule out both.

I think what I'm getting at is that, yes, marine transport is generally cheaper than air transport, presuming a lack of superscience tech, but there'll be a crossover point where air transport is cheap enough that the inherent disadvantages of water transport- lower speed and restricted waterside port access- will outweigh the relative cost advantage of the transportation mode itself.

[whswhs]

Originally Posted by Daigoro

For example, they might need to be clustered around a spaceport located on a wide, flat plain; or they might be free to locate in scenic waterside or mountain-side locales if they have easily accessible, high-speed transport.

This seems to point, though, to building your cities in orbit, perhaps in hollowed out asteroids. Easy for starships to get to without having to drop into and come out of a gravity well.

[Daigoro]

Originally Posted by whswhs

This seems to point, though, to building your cities in orbit, perhaps in hollowed out asteroids. Easy for starships to get to without having to drop into and come out of a gravity well.

Presumably though, citizens are going to want to live on the Gaia world that happenstance or terraforming has given them, and not just look at it from afar.

[malloyd]

Originally Posted by Daigoro

I think what I'm getting at is that, yes, marine transport is generally cheaper than air transport, presuming a lack of superscience tech, but there'll be a crossover point where air transport is cheap enough that the inherent disadvantages of water transport- lower speed and restricted waterside port access- will outweigh the relative cost advantage of the transportation mode itself.

I think that's *always* cheaper than air transportation lacking superscience.

The fact that water is hundreds of times denser than air, and hence will let you transport the same cargo weight in ships two to three orders of magnitude smaller without needing to use fuel (or carry engines) to counter gravity pretty well clenches it for anything where speed isn't absolutely critical. Which it never is on a regular cargo run - pipelines are the only transport method that come anywhere close to being as cheap as ships per ton-mile for much the same sort of reason, you don't need to move any part of the supply stream particularly fast if the stream is continuous.

[Daigoro]

Originally Posted by malloyd

I think that's *always* cheaper than air transportation lacking superscience.

But will breaking the cargo at a sea port to transport via land/air to its final destination somewhere inland always be cheaper? It's not the transport fuel cost I'm looking at, but the associated infrastructure. The cost of that infrastructure at distribution nodes might be such that the relative cost of the transport leg is negligible, whether by air or sea, and thus demand will naturally shift to the higher speed mode. It could be that the costs of all transport become so negligible that the civilisation uses the most convenient, rather than the marginally cheaper. And that depends on the tech assumptions.

ETA: To expand on my point about waterside ports- these won't always be in the most convenient place: they have to be on the water (of course), in a safe harbour, with enough frontage to handle the expected freight volume. A land-base distribution node can be more conveniently placed, not where coastal terrain determines it should be.
Also, coast-side real estate might be more valuable for housing than for industry, or it might be preserved for environmental or aesthetic reasons.

[tshiggins]

Originally Posted by whswhs

This seems to point, though, to building your cities in orbit, perhaps in hollowed out asteroids. Easy for starships to get to without having to drop into and come out of a gravity well.

This is one of my foundation assumptions in any even remotely hard-ish space campaign I think about designing: starships do not land on planets.

The first time I ever came across the notion was in C.J. Cherryh's Merchanter universe. The initial colony ships went out STL, with several thousand people (or families, I can't remember exactly), and took a generation or two to reach their destinations. The bulk of the habitat remained in orbit, and the colonists scouted the surrounding system for useful resources, as they began to survey the planet.

The colonial transport remained in orbit and became the core of a permanent station, and for a long time most of the colonists based out of it. Once they got a handle on the locations of the best resources in the system, they began to expand the station's infrastructure. Meanwhile, the colonists who dropped down the well began to carve out what they hoped would be a minimally-invasive zone that would allow them to provide needed biomass and nitrates and such, in support of the ongoing industrial space activities.

The idea was that all the heavy industry would remain in space, and only necessary heavy tools and equipment would drop down the well. Once down, the only things that ever came back up the well were people, varieties of food, and luxuries that really were only viable when grown on or taken from a planet.

(Nobody on the station wants to use its greenhouses for vineyards, for instance, or for hardwoods and fibers to make comfortable chairs).

The idea was that, with STL colonization, the colony had to be self-sufficient, but without making the same sorts of mistakes with the new planet that humanity made with Earth.

Anyway, I think that makes for a viable model. Preserve the planet's biome, as much as possible, by keeping all the heavy industry in space. That means the planet starts out with a single colony center, in a location with good river transport to deposits of resources mostly only needed for the planet's (very) light local industry.

Expand slowly out from there, and do so carefully, or the new world starts to look a whole lot like industrial-era Earth, with all the environmental problems that implies -- and that ruins your beautiful new Gaia planet.

For the most part, starships come in and dock at the station, and then advertise their goods on the local markets. They never really have any reason to land, unless the crew has skill-sets someone willingly contracts them to provide, or if the crew sees a financial opportunity for people who really won't be around for very long (this was Mal's specialty).

[malloyd]

Originally Posted by tshiggins

The idea was that, with STL colonization, the colony had to be self-sufficient, but without making the same sorts of mistakes with the new planet that humanity made with Earth.

This is in fact one of the problems with colonization by generation ships - why go anywhere? If being a self-sufficient station in interstellar space is a solved problem, why are you building a kilometer long starships and throwing them into space instead of a forest of kilometer tall towers sitting the Sahara?

[sir_pudding]

Originally Posted by malloyd

This is in fact one of the problems with colonization by generation ships - why go anywhere? If being a self-sufficient station in interstellar space is a solved problem, why are you building a kilometer long starships and throwing them into space instead of a forest of kilometer tall towers sitting the Sahara?

Panspermia? If we stay on Earth our lineage goes extinct sooner than if put eggs in different baskets.

Ideological freedom? If everybody lives in giant towers in the Sahara, you expect a fairly static and regimented social order. If you spread those same people out in a new solar system, they may feel like trading stability for freedom was worth it.

[David Johnston2]

Originally Posted by malloyd

This is in fact one of the problems with colonization by generation ships - why go anywhere? If being a self-sufficient station in interstellar space is a solved problem, why are you building a kilometer long starships and throwing them into space instead of a forest of kilometer tall towers sitting the Sahara?

It's a way of getting rid of people you'd rather not have as neighbours.