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

Greetings, all!

Some of you might recognize the term from MoO2. This is a type of garden worlds that is considered to have an extremely high Habitability - in fact higher than the homeworld. Notably, it's meant to represent the kind of condition that (a) allow a higher population cap for a given TL than a homeworld of the same size provides and (b) facilitates even better agricultural yields than our world's.

So I'm curious:
What should a planet be actually like in order to provide such benefits for us Terrans? For the sake of the experiment, assume that the planet's 'wild' ecosystem is loosely derived from and/or fully compatible with ours. It doesn't matter whether such a planet has been terraformed to such a state artificially, made by sufficiently advanced aliens, or just came about through infinitesimally unlikely luckiness.

Thanks in advance!

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

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

I suspect the conditions required to keep salinity low - the seas need to totally evaporate fairly often and move somewhere else - would be counterproductive, and you don't want to go too far toward smaller ones, Earth's huge oceans contribute a lot to the climate being nicer. A more even distribution might be nice though - there's a reason the seashore is densely populated and low density areas tend to be continental interiors.

A somewhat related and not so obvious option - high tectonic activity. Lots of volcanos might not seem that desirable, but they're great at keeping soil mineral levels high, and lots of rich and varied ores do nice things for the non-agricultural sector of your economy too. Losing a city or two a century to massive earthquakes or too close eruptions is a small price to pay really.

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

Minimal deserts, mountains, and other "non-arable" areas. Much of the land on earth is locked up in "Useless" deserts. The human population tends to be concentrated on a limited number of "bread baskets".

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

Not a problem if you just have younger oceans.

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

Raise the carbon dioxide level. On one hand, photosynthesis is more efficient with more carbon dioxide; in fact our current level is a bit lower than optimal, and some plants have apparently evolved a new photosynthetic pathway to adapt to this. On the other hand, you'll get warmer temperatures, and I've read that cold is more lethal than heat. Certainly this amounts to a recommendation for global warming, but some of the issues with global warming appear to relate more to the rate at which it takes place and the difficulty in adapting to changing climate and sea level in a hurry than to the absolute levels. Of course you wouldn't want the classic SF Venus, but something like Earth in the Eocene might have its advantages.

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

Change costs somebody money. Global cooling wouldn't be any more welcome.

In the *really* long run, I'm not so sure Golden Age Venus would be going too far. Ultimately if it has more biomass, I'd think a civilization that could control the same fraction of it and redirect it for its own purposes would be richer for it. Differently than we are now perhaps, but better off.

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

That doesn't sound like Gaia for humans, it sounds like Gaia for crops. Which I suppose is good enough. As long as we can still breathe the air and go shirtsleeve and don't get knocked over by super hurricanes.

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

Actually that planet sounds awful. We'd fight over it to much and most of us would end up as serfs just to get some protection.

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

My experience is that people like living in places that have vegetation. And having warming weather is popular too; an awful lot of people go to warm places on their holidays.

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

Yes, well, if you really value your independence you can go live in some desolate mountain, desert, or arctic region. There are tradeoffs everywhere.

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

Too much variability in what people like and can adapt to to make generalizations, I think.
Up until a few years ago, temperatures above 80 would have been hell. Now I'm wearing two shirts, a coat, and a warm hat indoors when it's only 67.

There are plenty of jokes involving scenes of what 60 degrees in Canada vs. California look like.

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

Differences in measurement systems will do that. 60 degrees in Canada is 140 degrees in California...

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

That's a different image showing 50 and 100 degrees in California and in Britain. But with the 100 in Britain showing lava and sarcastic looking skeletons.

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

For making generalizations, looking at the average behavior is the standard method. Things that large numbers of people do have a large influence on the average. Of course the average does not predict the behavior of an individual, or even of an atypical population. But that's not what it's for.

"I don't know how Nixon won. Nobody I know voted for him." (Pauline Kael, I believe.)

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

On the other hand, just because I like sea bathing doesn't mean I won't to be pickled in brine. Dense jungles during monsoons aren't nearly as popular as manicured parks in mild weather. Overall, I wouldn't peg a hot humid planet with highly chaotic high energy weather systems as a "gaia" world and that's what you could get with a dense wet atmosphere with relatively high partial CO2 pressures.

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

That doesn't mean that we are at the optimal level (or even above it). The optimum might be lower than you describe, but higher than where we are. The fact that you can envision a higher point that's undesirable doesn't establish that every higher point is undesirable.

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

Indeed, the very premise here is that there exists possible planets that are more habitable than homeworlds! Sure, but ericthered specified "As long as we can still breathe the air and go shirtsleeve and don't get knocked over by super hurricanes."

To which you responded that people like vegetation and warm weather. Which in context seems almost euphemistic, like a colony program trying to sell a hothouse as a paradise.

"What's it like there?"
"The habitable zone is mostly dense rainforest with an average surface temperature of 40 degrees and nearly 100% humidity. There's also two permanent cyclonic systems."
"So put 'lush vegetation and warm weather' in the brochure!"

Which seems to say that a hypothetical gaia would need to be at a stable equilibrium state that's rather high entropy and just short of mama bear's porridge.

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

To me a "Gaia" type world is going to be an idealized version of Earth as far as what a human would think.

So first off gravity is going to be 1 gravity.
The world with most likely be 2/3 to 3/4 water, mostly in oceans.
All Terran crops and animals can live and thrive on the world without any adaptation.
All native crops and animals can be consumed without any adaptation.
Axial tilt of the world will be roughly 23.5 degrees, so seasons and weather patterns should be close to Earth normal.

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

That's Earth, which is by definition not a Gaia world.

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

Add into this a lack of arid, sandy, and extremely rocky mountainous regions, permitting greater arable land for farming and herding.

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

I'd go with most of this. The low axial tilt seems obvious, as does high nitrogen content of the soil. There's a lot to be said for properly twisted amino acids, because that means humans can eat the native plants and animals, even though it means the native animals and pathogens can also eat us.

I don't think low-salinity oceans is a viable expectation, but a better distribution of ocean and land would be nice. A dozen or so land-masses the size of Australia, distributed more or less evenly around the planet, might work out well, especially if they were connected with archipelagos. That means a lot of shallow waters teeming with life, and the lack of really huge expanses of open ocean minimizes the intensity of coriolis storms.

I hadn't thought of the vulcanism thing, but that makes sense, too. Also, I'd say no huge extremes in altitudes. No mountains larger than about the Appalachians or the Pyrenees, which result in minimal rain-shadows or other atmospheric weirdness.

Lots of flora and fauna, everywhere.

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

It's the expectation if you terraform an arid world, until the new seas have had time to dissolve salts anyway, which takes megayears.

I could also imagine biogenic processes that clean oceanwater on a natural gaia.

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

No, actually, I was responding to "That doesn't sound like Gaia for humans, it sounds like Gaia for crops." That's why my primary point was that in my experience, humans enjoy places with vegetation. I was saying that Gaia for crops very like WAS Gaia for humans.

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

I did say IDEALIZED.

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

To try and dress this up with semi-plausible geophysick-y technobabble let's say that we have a world where Earth-like continent forming didn't happen and the preferred method of landmass creation is magma plumes forming large volcanic islands over time. Further, the magma plumes cluster in the equatorial regions putting a planet-surrounding belt of these island in the tropics.

So basically we're mass-producing Hawaii. I won't swear it's an optimum human habitat but it'd be a great place to sell real estate. That might be because the human types would be voting with their feet and money to move there telling you that they thought it was pretty close to an optimum habitat.

Note that the "big island" actually is quite big and gives you not only warm coastal regions but fertile and comfortable uplands as well.

You could also build high altitude observatories and/or spaceports on the peaks of the mountains that had gone cold.

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

I don't know if I'd like to live in Hawaii; I'm actually liking Riverside's climate now that we've moved there, and I think Hawaii's a lot wetter, isn't it? But it's an elegant handwavy concept for a planet.

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

A drier part of the island is where those uplands come in. You get grasslands instead of rain forests but it's still in the 70s every day.

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

I was thinking of kind of a super-goldilocks situation, where the the planet is exactly the right size and density, in exactly the right orbit, with exactly the right atmosphere to just have perfect greenhouse conditions without a runaway so that warm temperatures are fairly evenly distributed around the planet.

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

Let's consider Planet Optimum, the best planet you can randomly roll.

Dense Breathable Atmosphere, hydrographic percentage of between 80 and 90%, default climate type warm, medium vulcanism. light tectonic activity, RVM +2, Habitability +6, .75 density. 1.0 gravities. Black Body temperature 312, Diameter 1.33 resulting in an optimum TL 10 carrying capacity of 6.637 billion human beings. This is nearly the maximum carrying capacity possible. Most of the garden planets you actually roll will be able to comfortably support less than half that many humans. As you know Bob, by GURPS rules, Earth is well above its carrying capacity leading to most of the planet living at much less than a TL 8 average income.

You actually want a higher hydrosphere than that of Earth because oceans are a much richer resource than deserts for food production. Relatively small continents will be wetter and more fertile. Low density increases diameter, and diameter increases carrying capacity. As for increasing habitability above the random maximum, that would pretty much require native plant life that somehow manages to be more efficient in converting sunlight into calories, as well as native life that is really good at identifying and fertilizing tapped out soil.

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

The big island has rather little arable land being mostly volcanic.

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

Planet earth with green Sahara and green Australia hypotheses fulfilled would probably fulfil the criteria.

I think this has more to do with continent arrangement and prevailing winds than gross physical properties.

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

Deserts tend to develop in continental centers, so more numerous smaller land masses should keep giant human-inhospitable zones to a minimum.

Slightly higher oxygen levels would make little difference at sea level but help those living at high elevations.

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

When asked about what terrain they would like to live in, or have pictures of on the walls, etc. most people go with where they grew up as number one, but number two is very often a plains-type environment like the one where we evolved.

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

I know that, while I grew up in the lush Appalachian foothills of southeastern Kentucky, I much prefer Denver's semi-arid climate. The days don't get quite as hot in the summer, as Kentucky did, and the lack of humidity makes it feel at least 10 degrees cooler, still.

Additionally, the evenings cool down nicely, here, whereas in Kentucky it was hot and steamy throughout the night. Moreover, if I really want to escape the heat, I go to the mountains for a couple of days. Even in the hottest part of the summer, the nights at 12,000 feet (3.7 km) usually see temperatures in the mid-40s Farenheit (7-9 degrees, Celsius), while the days are in the mid-70s F (23-26 C).

Out on the Eastern Plains it gets a little warmer, but even there it cools down at night. The lack of trees kinda sucks, though, and I do sometimes miss Kentucky's deep forests.

Here in the Front Range piemont region, though, it's a nice mix of prairie, rolling hills, foothills, and light forests, with a fair number of small streams and small rivers. Add in a pretty nice city with few of the problems experienced in larger urban areas, and Colorado is pretty optimal, generally speaking.

I think that climate pretty much supports your notion that, for many people, our evolutionary heritage makes this a nigh-perfect climate, albeit a bit cooler than the Rift Valley, in Africa.

The winters, here, are different than most people think, too. In good years, the snow gets pretty deep in the mountains, but Denver stays cool, clear and dry during the days (although it does get really cold, at night). These days, we see temperatures in the 50s and 60s, with sunny conditions, on many winter days (that's significantly warmer than when I was a kid, here, and most days were in the low 40s to low 50s, but still clear and dry).

This is a good year. The Pineapple Express that has drenched California brought steady snows to the Colorado mountains, and the snow-pack is significantly above average. If we get a wet spring, then we may have some local flooding problems.

However, the reservoirs were already pretty full from the incredibly wet spring two years ago. Lake Powell will likely see more water in the reservoir than in many years, starting in a month or two.

https://www.wcc.nrcs.usda.gov/ftpref...mal_update.png

http://www.cbrfc.noaa.gov/wsup/pub2/...on/current.pdf

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

http://www.to-hawaii.com/agriculture.php

.....says that 40% of Hawaii's land is farmland. This is after a real estate boom with prices that could make a Californian blink.

There's a lot more to Hawaii than the beaches and the slopes of Mauna Kea and Mauna Loa.

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

Anyhoo, I would guess there's a lot of shallow seas, since they are much more productive than deep seas.

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

Agreed. I don't know how necessary deep seas are for life. I'm sure they have some role or the other, but we'd want this world to have lots and lots of continental shelf.

I read somewhere that deserts tend to form over the tropics of capricorn and cancer, with the exception of tall mountain ranges. So more careful landform positioning would help with that. It might be a great place to put these shallow seas.

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

That doesn't seem consistent with the demographics of people leaving small towns in the interior for cities on the coast. Personally I like where I live now a lot more than isolated military installations in the Midwest and the desert, both in terms of climate and culture.

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

That's for the entire state not per island. At least as far as I could see. I just go by what the people on the island told us when we visited for a wedding and during the big island tour.
Why our friends chose the middle of summer for their nuptials I'll never understand. My sweat glands never forgave them.

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

While my preferences made a radical 180 about three or so years ago. Cold, damp, and dark to now I need it warm, dryish, and bright.

I do remember reading about how the U.S. population demographics changed greatly with the advent of affordable air conditioning.
That seems to suggest that on our own, most people don't like the heat 24/7 or year round.

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

People base where they live on more than just the terrain. For instance, they may move to where the jobs are.

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

Urbanization is terrain. However I also like beaches and temperate weather almost as much as like stuff that is open past six pm and busses that aren't hours apart and I gather beaches and temperate climates are pretty popular with other people.

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

In a limited degree, yes. But few people are primarily influenced to move to cities by the desire for large areas without vegetation or soil, or for a locally higher temperature, or other geographic traits, I think. Not by comparison with relative social anonymity, or more specialized businesses, or a greater extent of the market, or cultural variety, or other features of city life, which, to be sure, not everyone likes, but which attract a significant number of people.

And to a large degree, the places that can become urbanized are geographically limited. The distribution of cities across the Earth is not random. One thing to consider might be the features that would make a planet likely to have lots of urbanization.

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

Mainly, I find the thesis that most people really want to live in their hometown and only emigrated (or immigrated) for work to be dubious.

Most of the places I grew up were only there because nobody else wanted them.

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

I'd say that whether people remember their home town fondly or not is more about how they felt about the other citizens than the local climate and ecosystem.

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

This is true, but it should be noted that the historical factors for locating on rivers and harbours- access to shipping, water and fishing- may or may not be relevant to a space-faring civilisation that are free to choose their population centres from scratch.

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.

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

Like I said, there are many reasons people move. Not only homeland terrain, not only work.

Do you have data that show that they move because they prefer the terrain at the new place, not something else about it?

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

I am not sure how much this would change, once things are up and running the bulk of goods are going to be moving around on the planet and moving stuff around by water is still going to be one of the cheaper options.

Also I don't really buy the notion of colonies starting out as a single large city and a sparsely populated hinterland. Personally starting from a number of smaller town/ village sites located near strategic resources makes more sense. Water transport if it is possible is a logical way to tie these together.

Ditto water supply, early colonies are going to want to go where the water is (as far as is possible) rather than messing around building and maintaining long pipelines. Unless there is a life or death reason for using a specific site I would figure that colonists (or more likely advanced scouts) will pass over sites with severely restricted water supplies.

Placing a main space port might be an exception, it depends upon the technology in use, but I can still see planners prefering sites on either the coast or navegable rivers. Technology permitting I could even see spaceports being located offshore.

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

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. High tech cargo dirigibles (like this sexy beast), if cheap enough, could possibly also break the dependency on water transport. You'd need a detailed technological and economic model to determine which modes of transport are more viable and desirable before deciding on town placement.

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.

Well, this is a possible Gaia planet, so there might be pleasant afternoon showers every day to refill the city's reservoirs. Or they might be high tech enough to effect complete moisture recovery and recycling, meaning an external water supply would only need to make up for inefficiencies in the system.

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

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.

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.

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.

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

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.

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

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.

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

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.

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

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.

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

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.

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

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).

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

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?

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

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.

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

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

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

Same reason anyone does something that isn't of low risk short term benefit to themselves. Ideology.
Problem of course is that ideology isn't genetic and subsequent generations will almost certainly disagree with the first set.

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

I costs *trillions* of times as much per undesirable as bullets would....

Sending undesirables to the colonies is a way of getting some useful labor out of them - which assumes a colony that exists for some other reason and has a labor shortage - not of getting rid of them. Nobody who did it historically would have had strong moral objections to executing their undesirables instead.

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

Didn't transportation to Australia replace hanging for a lot of offenses?

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

Sure... and that was to a colony with a labor shortage and a captive market for English goods.

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

What's the difference between a space colony and generation ship? Basically, the latter has a variety of additional systems (fuel tanks, drive systems, etc) that, for a given price, cut down on the number of people you can have. I think I've seen it floated around that the minimum starting number that avoids risk of extinction is something like 500. Let's double that, to 1000.

How much of a drop do you see between the carrying capacity of a colony and the carrying capacity of a similarly-priced generation ship? 1:1000 seems a bit extreme, but let's go with that. This means that, for a given price, we can either send 1,000 people off on a generation ship (or fleet of ships), or have 1,000,000 in colonies. The latter's the better bet, right? Short term, yes. Long term, though, when those 1,000 people (or, rather, the current generation descended from them) reach a habitable world? They could grow to over a billion individuals. So, for 1/1000th the starting population*, you end up with 1000x the end number of people, for a given price. If your purpose in colonizing other worlds is to result in more people existing, the generation ship is a better bet.

Granted, you could instead have a generation ship that isn't meant to actually establish a colony anywhere, but instead mines asteroids and the like to build more generation ships, but building infrastructure on a habitable planet is probably a lot easier than doing so out in space, and a colony-killing event is probably much less likely on the planet as well.

*Technically, you could start the space colony with only 1,000 people, and let them breed until they reach capacity.

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

I'd have thought you'd need a deep ocean to act as a heat sink and thermal regulator for the whole system.

Also, perhaps you need a "non-productive" base of the food chain, producing tons of plankton and higher animals, to enable there to be productive consumable species around the shallower coastal areas.

As for the planet itself, is there some arrangement of 2 or more suns that would give it a more steady level of insolation to help with crop growth and weather patterns?

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

We can have large continental shelves and then really deep oceans between them.

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

Generation ships can't be supplied from the outside. They are strictly restricted to the resources they leave with and must be self-sufficient for centuries. They have no way of getting rid of excess population except by recycling it.

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

That's an emphatic no. With two suns either the second one is so far away it doesn't matter or if the planet rotates around the center of mass of a close binary pair the issue becomes "is this planet still habitable?".

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

But you can find circumbinary planets in the habitable zone, such as Kepler-47c. This one isn't exactly a candidate for a Gaia planet, but it means they can't be completely ruled out.

There's also Asimov's Nightfall, which has a planet with 6 suns in the sky and perpetual daytime- although I don't know how viable such a system actually is.

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

I can't imagine how adding another massive variable like a star could make things more stable than our system.

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

The general three body problem is not only unsolved, it may very well only be solvable under very specific conditions.

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

There are ways around those problems. Primarily, you get around them by have a generation fleet, rather than a single ship, with good shuttles that can go between them. If something goes wrong - parts malfunction, a string of unanticipated births puts a ship over its carrying capacity (contraceptives got mixed up with sugar pills, maybe), etc - you can offload the issue to other ships in the fleet until the problematic one is properly running again. Granted, this means the fleet as a whole must be self-sufficient, but I'm assuming that a proper space colony would also be self-sufficient, and the problem with generation ships isn't this requirement so much as the fact help isn't anywhere to be found if something goes wrong (whiereas with a colony, they can just order supplies from Earth).

While it's en route, a generation ship will always have more issues than a space colony - the above helps mitigate this, but doesn't completely eliminate it. If the journey is short enough for the fleet to survive on its own, however, then the only investment needed is that first push to send it off, whereas with a space colony you'll always need to be helping/resupplying it (because issues are inevitable, and with relatively easy access to an established civilization you don't need as much redundancy as you do with the generation fleet).

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

I'm not sure why stability is an issue, the planets orbit the barycentre of the two stars.

Circumbinaries in the habitable zone have been discovered and seem to be a common occurrence.
"Kepler-453 b resides in the habitable zone of its host pair of stars, a surprisingly common occurrence for the circumbinary planets discovered by the Kepler Space Telescope. But because Kepler-453 b is larger than Neptune, it cannot be habitable."

You can also do your own modelling and see some actual habitable zones here.

ETA: Another quote:
"It is just as easy to make an Earthlike planet around a binary star as it is around a single star like our sun. So we think that Tatooines may be common in the universe."

ETA2: And an academic article proposing that circumbinaries are more likely to support life than even Earth itself.
Habitability properties of circumbinary planets
In this article, it is argued that several habitability conditions (in fact, at least seven such conditions) appear to be fulfilled automatically on the circumbinary planets of main-sequence stars (CBP-MS), whereas on the Earth these conditions are fulfilled only by chance. Therefore, it looks natural that most of the production of replicating biopolymers in the Galaxy is concentrated on CBP-MS of particular classes, and life on Earth is an outlier, in this sense.

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

I personally live in a really hot place and it sucks. My biology is extremelly ill adapted for the sun and heat

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

Sure, but generalizing from a single case is risky.

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

Still, naked, healthy humans do much better in moderate to extreme heat than moderate to extreme cold. Darn few do well sleeping nude in 40 degrees, for example.
But we may wish to take outliers into consideration. Even if healthy citizens could handle or even enjoy extreme cold, could we say the same about the sick or elderly?
Gaia means perfect in this thread, but perfect for who is a valid question that needs answering first.

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

I didn't say the planet was "impossible". I said it raised serious questions about it remaining _habitable_.

In the simplest circumbinary situation insolation varies by 100%. That would or should do drastic things to climate. If one of the stars is much smaller than the other the variability gets worse. Large amounts of variability are not Gaia-like and there is _no_ arrangement that will give you more stable insolation.

Also, really close binaries might be a short-lived arrangement not likely to endure for the multiple billions of years needed for plant formation.

As for Nightfall, when Asimov wrote that it nether he nor anyone else know _anything_ about stellar evolution or planetary formation. The system was a literary device only.

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

That wasn't the stated premise. It was, "This is a type of garden worlds that is considered to have an extremely high Habitability - in fact higher than the homeworld. Notably, it's meant to represent the kind of condition that (a) allow a higher population cap for a given TL than a homeworld of the same size provides and (b) facilitates even better agricultural yields than our world's." Both of those statements are statistical generalizations about entire populations and planetary ecologies. You aren't going to get a planet that's a perfect fit for every single inhabitant, even if its carrying capacity greatly exceeds Earth's.

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

I'm also pretty sure that Asimov didn't compute the orbital mechanics of a planet in a system of six stars.