I'm making a conworld, where the setting is floating/flying colonies above an ice giant (think similar to Neptune). Just trying to make out the specifics of how this would work... Like breathing for example. Neptune's atmosphere is mostly hydrogen followed by helium, methane, ethane, with ice clouds of ammonia, water, and methane. Obviously I can have a different composition but I'd like to make it a realistic as possible. I know you can split water into hydrogen and oxygen but what to do with the hydrogen after? I mean you can burn it, well you can burn most ofthe gases in the atmosphere, but that requires oxygen. so I'd require an atmosphere that contains oxygen naturally really...
Just thinking out loud here and hoping someone will pop in with something helpful.
Floating colonies above an ice giant
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KathTheDragon
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Re: Floating colonies above an ice giant
You could probably use it in part of some sort of air recycling system.
Re: Floating colonies above an ice giant
Indeed, but I'd like multiple structures that people travel between, but I'd like this to be quite low technologically, as paradoxical as that sounds... Like if it can be made so people can travel between the structures without the need for space suits then that'd be awesome...
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Salmoneus
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Re: Floating colonies above an ice giant
But (except with a very broad definition of 'space suit') almost certainly impossible.
On a gas giant, there's a height where you have a liveable atmospheric pressure, and there's a height where you have a liveable temperature. Unfortunately, these are a long, long way apart. On the 'surface' of Uranus, for instance (i.e. where you get earthlike atmospheric pressure and gravity), it's about 80K. I.e. outside the habitat you won't live long enough to notice. Alternatively you could go deeper, but then you'd have pressure equivalent to the deepest that scuba divers have ever gone - it's probably survivable, but I really wouldn't recommend it if you can avoid it. If you're swimming around in pressures that nuclear submarines can't cope with, it's probably not good for you (not to mention the hassle of reacclimatising). Not to mention that at that height gravity may be quite unpleasant.
So if possible, stay at surface level and just wear a spacesuit. A really, really, really warm spacesuit.
Of course, the other problem (if you need more) is the wind. I'm not sure of the exact windspeed at surface level on a gas giant, but you're talking FAST. As in holding on to a missile fast. Theoretically, so long as everything's moving at that speed, there's no problem - but the slightest turbulence, and at best you're vomiting, at a little worse you're flung miles away from your habitat, and at worst you're spun around so fast your heart stops working and/or you get ripped apart.
Moral of the story: when living on a gas giant, avoid EVAs if at all possible. Always be in the biggest, warmest (and with the best suspension if you don't want to be drowning in vomit) vehicle you can be in. Gas giants are surprisingly hospitable... but they're still not designed for people.
[Venus is a bit better - there, you get earthlike temperature, pressure and gravity all at the same height, plus the atmosphere has way more resources. And the wind is hurricane strength but not tear-you-limb-from-limb strength, so EVAs should be possible. Not without a spacesuit, though - leaving aside the wind, the sulphuric acid would make that a very unattractive option]
On a gas giant, there's a height where you have a liveable atmospheric pressure, and there's a height where you have a liveable temperature. Unfortunately, these are a long, long way apart. On the 'surface' of Uranus, for instance (i.e. where you get earthlike atmospheric pressure and gravity), it's about 80K. I.e. outside the habitat you won't live long enough to notice. Alternatively you could go deeper, but then you'd have pressure equivalent to the deepest that scuba divers have ever gone - it's probably survivable, but I really wouldn't recommend it if you can avoid it. If you're swimming around in pressures that nuclear submarines can't cope with, it's probably not good for you (not to mention the hassle of reacclimatising). Not to mention that at that height gravity may be quite unpleasant.
So if possible, stay at surface level and just wear a spacesuit. A really, really, really warm spacesuit.
Of course, the other problem (if you need more) is the wind. I'm not sure of the exact windspeed at surface level on a gas giant, but you're talking FAST. As in holding on to a missile fast. Theoretically, so long as everything's moving at that speed, there's no problem - but the slightest turbulence, and at best you're vomiting, at a little worse you're flung miles away from your habitat, and at worst you're spun around so fast your heart stops working and/or you get ripped apart.
Moral of the story: when living on a gas giant, avoid EVAs if at all possible. Always be in the biggest, warmest (and with the best suspension if you don't want to be drowning in vomit) vehicle you can be in. Gas giants are surprisingly hospitable... but they're still not designed for people.
[Venus is a bit better - there, you get earthlike temperature, pressure and gravity all at the same height, plus the atmosphere has way more resources. And the wind is hurricane strength but not tear-you-limb-from-limb strength, so EVAs should be possible. Not without a spacesuit, though - leaving aside the wind, the sulphuric acid would make that a very unattractive option]
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But the river tripped on her by and by, lapping
as though her heart was brook: Why, why, why! Weh, O weh
I'se so silly to be flowing but I no canna stay!
But the river tripped on her by and by, lapping
as though her heart was brook: Why, why, why! Weh, O weh
I'se so silly to be flowing but I no canna stay!
Re: Floating colonies above an ice giant
Maybe you could go with a "Hot Jupiter" - type giant relatively close to it's star. The temperature might be more livable and you might have a lot of water vapor in the atmosphere, which shouldn't be too hard to pull oxygen out of if you have a reliable power source that doesn't require combustion. Gliese 876 c might be a good choice.
Re: Floating colonies above an ice giant
Also (just making this explicit, in case it wasn't clear from your post Salmoneus), even though 80K might seem a little warmer than the vacuum of space (4K), it is in reality much colder, because atmosphere.Salmoneus wrote:But (except with a very broad definition of 'space suit') almost certainly impossible[...]it's about 80K. I.e. outside the habitat you won't live long enough to notice[...]So if possible, stay at surface level and just wear a spacesuit. A really, really, really warm spacesuit.
Space, being a vacuum, has no medium to carry heat away, so a naked human in space doesn't lose heat very quickly except for the water that boils off of them. Besides the atmosphere, the main purpose of a spacesuit is to provide an Earth-like atmospheric pressure, since the lack of pressure can damage the blood vessels close to the skin. An elastic suit (with a rigid helmet) could accomplish the same role, and has the advantage that a small tear can't cause depressurization over the whole body.
In the upper atmosphere of a gas giant, however, you have an insanely low temperature (80 K is -315.67 F {for us crazy Americans} or -193.15 C {for everyone else}) and the same kind of atmosphere you have on Earth. That means that it will feel at least as cold as -315 F would on Earth (keep in mind that that's about 180 degrees colder than the coldest temperature ever measured on Earth), and probably much, much colder because of the aforementioned nightmarish winds.
Habitats built in the upper atmosphere would be more difficult to heat and insulate than space habitats, but it's not as bad as with people: the surface-area-to-volume ratio decreases linearly as you scale up, so a 100m sphere is 100 times easier to insulate than a 1m sphere. The downside of course is that it requires 1 million times as much energy to heat to the same temperature.
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Lyhoko Leaci
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Re: Floating colonies above an ice giant
Another note on the temperature: Nitrogen liquifies at 77K, while oxygen liquifies at 90K. If it's cold enough that the air itself is turning to a liquid, you do NOT want to be out in it. Then there's the fact that liquid oxygen has a tendency to cause things to burn quite vigorously, even at the low temperatures involved.
As for the gravity, going deeper into the atmosphere to find a warmer spot won't change that too much, (and in the cause of Uranus, will likely make it more Earthlike, as the gravity at Uranus's "surface" is .89 times that of Earth.) the increase in pressure would be the main problem. Gliese 876 c is relatively close in mass to Jupiter, which would likely mean that it's gravity is too high to be comfortable.
Your best be would probably be a Uranus or Neptune sized planet in the habitable zone so the temperature, pressure and gravity all work out to be reasonable, but there's still the wind to deal with.
As for the gravity, going deeper into the atmosphere to find a warmer spot won't change that too much, (and in the cause of Uranus, will likely make it more Earthlike, as the gravity at Uranus's "surface" is .89 times that of Earth.) the increase in pressure would be the main problem. Gliese 876 c is relatively close in mass to Jupiter, which would likely mean that it's gravity is too high to be comfortable.
Your best be would probably be a Uranus or Neptune sized planet in the habitable zone so the temperature, pressure and gravity all work out to be reasonable, but there's still the wind to deal with.
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Re: Floating colonies above an ice giant
Another fun problem to deal with is the common occurrence of electrical discharge phenomenon, like lightning and St. Elmo's fire. Whoever is out there will have to be accustomed to their hair standing on end, at the very least.
Re: Floating colonies above an ice giant
Hot jupiters, or any kind of jupiter, have incredibly powerful magnetic fields, which is an additional detail. A colony on giant planet would have a much easier time on one of its moons.
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Salmoneus
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Re: Floating colonies above an ice giant
Actually, I'd like to defend the idea of gas giant cities (if only because my own sci-fi setting uses them).
Although the above problems will be completely lethal to anybody going outside, they shouldn't be major problems for large habitats.
The temperature problem isn't as much of a problem as it looks. You've got to balance the problems of losing heat due to the cold and of not losing enough heat - a great big mechanical sky-city will be generating a hell of a lot of waste heat that it wants to dissipate. Now, in space, despite it being colder, the lack of an atmosphere means that overheating is the main problem; I'm not sure at what temperatures and pressures the cold becomes more of an issue, but it should at least mean that the cold isn't as much of an issue as you might think (and that maybe earthlike temperatures may not be ideal, if it costs more to dissipate the waste heat, particularly since the things that dissipate heat (great big fins) are also things that make wind more of a problem)). Think of gigantotherms on earth - over a certain size, things can be hot-blooded without having to heat their blood, because the normal waste heat takes so long to dissipate that they're always warm, even if they're way down in the ocean. True, Uranus is colder, but then a habitat is both bigger and more heat-generating than a turtle.
The wind likewise becomes less of a problem as you get bigger. If you're really big, and really streamlined, you may not have too much trouble if you steer out of the worst of it. And of course what you'd really want to do is have a 'momentum-lock' sort of thing, a layer of fluid between the outer skin and the inner habitat, that would let the outside be shaken around while leaving the inside alone. If you had a spherical habitat and a sufficiently slippy suspension fluid, you could even have your outer skin thrown around 180 degrees and not notice it...
Contrariwise, sky cities have some massive advantages over moons. Specifically, two of them:
- you can't live on moons because they don't have enough gravity
- you can't live on moons because you'd be irradiated
- temperature is still a problem
- resources
On the first: humans appear to need gravity to survive, in the long term (particularly if you're going to be doing things like having babies) Now, we haven't done enough tests to establish exactly what levels have what effect, so this is one of the big grey areas for SF writers. But it would seem that low-gravity moons are at best unhealthy and at worst, in the long term, unliveable.
Similarly, low-grav moons have minimal atmosphere. So you die. This can presumably be dealt with with a sufficiently robust skin, but that costs a lot of money.
Moons are even colder that gas giants. Yes, as observed above, you don't have the wind chill to contend with, but you still can't easily go outdoors. And the lack of windchill may actually be a problem: like space stations, your moon-colonies are liable to overheat without a robust atmosphere to dissipate the heat as quickly as you generate it.
And why would you go to a moon? There's nothing there. There's not a lot on gas giants, but at least there's gas. For instance, most gas giants have plenty of combustible hydrocarbons to exploit - even if they're not worth exporting they might be able to reduce your costs. Or if you've got the right type of fusion, there's helium-3.
Some of these problems can be reduced by picking an icy moon, boring through to an underice ocean, and building a big rotating torus - that gives you gravity and the liquid helps you dissipate heat, while the ice sheet keeps you safe from radiation. But that all costs a lot of money (eg you'll have to be continually re-boring your entry shafts as the ice shifts).
Although the above problems will be completely lethal to anybody going outside, they shouldn't be major problems for large habitats.
The temperature problem isn't as much of a problem as it looks. You've got to balance the problems of losing heat due to the cold and of not losing enough heat - a great big mechanical sky-city will be generating a hell of a lot of waste heat that it wants to dissipate. Now, in space, despite it being colder, the lack of an atmosphere means that overheating is the main problem; I'm not sure at what temperatures and pressures the cold becomes more of an issue, but it should at least mean that the cold isn't as much of an issue as you might think (and that maybe earthlike temperatures may not be ideal, if it costs more to dissipate the waste heat, particularly since the things that dissipate heat (great big fins) are also things that make wind more of a problem)). Think of gigantotherms on earth - over a certain size, things can be hot-blooded without having to heat their blood, because the normal waste heat takes so long to dissipate that they're always warm, even if they're way down in the ocean. True, Uranus is colder, but then a habitat is both bigger and more heat-generating than a turtle.
The wind likewise becomes less of a problem as you get bigger. If you're really big, and really streamlined, you may not have too much trouble if you steer out of the worst of it. And of course what you'd really want to do is have a 'momentum-lock' sort of thing, a layer of fluid between the outer skin and the inner habitat, that would let the outside be shaken around while leaving the inside alone. If you had a spherical habitat and a sufficiently slippy suspension fluid, you could even have your outer skin thrown around 180 degrees and not notice it...
Contrariwise, sky cities have some massive advantages over moons. Specifically, two of them:
- you can't live on moons because they don't have enough gravity
- you can't live on moons because you'd be irradiated
- temperature is still a problem
- resources
On the first: humans appear to need gravity to survive, in the long term (particularly if you're going to be doing things like having babies) Now, we haven't done enough tests to establish exactly what levels have what effect, so this is one of the big grey areas for SF writers. But it would seem that low-gravity moons are at best unhealthy and at worst, in the long term, unliveable.
Similarly, low-grav moons have minimal atmosphere. So you die. This can presumably be dealt with with a sufficiently robust skin, but that costs a lot of money.
Moons are even colder that gas giants. Yes, as observed above, you don't have the wind chill to contend with, but you still can't easily go outdoors. And the lack of windchill may actually be a problem: like space stations, your moon-colonies are liable to overheat without a robust atmosphere to dissipate the heat as quickly as you generate it.
And why would you go to a moon? There's nothing there. There's not a lot on gas giants, but at least there's gas. For instance, most gas giants have plenty of combustible hydrocarbons to exploit - even if they're not worth exporting they might be able to reduce your costs. Or if you've got the right type of fusion, there's helium-3.
Some of these problems can be reduced by picking an icy moon, boring through to an underice ocean, and building a big rotating torus - that gives you gravity and the liquid helps you dissipate heat, while the ice sheet keeps you safe from radiation. But that all costs a lot of money (eg you'll have to be continually re-boring your entry shafts as the ice shifts).
Blog: [url]http://vacuouswastrel.wordpress.com/[/url]
But the river tripped on her by and by, lapping
as though her heart was brook: Why, why, why! Weh, O weh
I'se so silly to be flowing but I no canna stay!
But the river tripped on her by and by, lapping
as though her heart was brook: Why, why, why! Weh, O weh
I'se so silly to be flowing but I no canna stay!
Re: Floating colonies above an ice giant
Thanks for all the suggestions and science.
There's my notes so far:
Floating platforms above a gas giant (technically ice giant).
The atmosphere above the ice giant is rich in hydrogen, methane, water, carbon dioxide, and trace oxygen, and helium.
They extract the hydrogen and methane for fuel, and extract breathable oxygen from the carbon dioxide.
The structures also have air farms, where plants are grown to generate oxygen from the carbon dioxide. The plants include algae and other plants.
The ice giant is in the habitable zone of the solar system, keeping temperatures in the upper atmosphere comfortable.
To travel between structures air tanks/masks are needed, but space suits aren't. (possibly?) Propulsion is needed also.
The structures generate power three ways: solar panels on top, gaseous scoops, and geothermal tendrils. Gaseous scoops could be inside the tendrils, drawing gas from the lower atmosphere.
The structures are called Pleumons, Latin for jelly fish, because of the domed top and the geothermal tendrils. [I know that's not the correct pluralisation, so a Latin speaker may be able to help me there.]
There's my notes so far:
Floating platforms above a gas giant (technically ice giant).
The atmosphere above the ice giant is rich in hydrogen, methane, water, carbon dioxide, and trace oxygen, and helium.
They extract the hydrogen and methane for fuel, and extract breathable oxygen from the carbon dioxide.
The structures also have air farms, where plants are grown to generate oxygen from the carbon dioxide. The plants include algae and other plants.
The ice giant is in the habitable zone of the solar system, keeping temperatures in the upper atmosphere comfortable.
To travel between structures air tanks/masks are needed, but space suits aren't. (possibly?) Propulsion is needed also.
The structures generate power three ways: solar panels on top, gaseous scoops, and geothermal tendrils. Gaseous scoops could be inside the tendrils, drawing gas from the lower atmosphere.
The structures are called Pleumons, Latin for jelly fish, because of the domed top and the geothermal tendrils. [I know that's not the correct pluralisation, so a Latin speaker may be able to help me there.]
Re: Floating colonies above an ice giant
I think there is much on moons that is not available on gas giants. the notable items on that list are metals and rocks, but also stuff in general: you know, carbon, oxygen, silicon... There simply isn't much on gas giants: sure, there is much fuel: most notably hydrogen [which burns pretty nicely], but you still need the oxygen to burn it. Gas giants are, well, big balls of gas... I've always figured colonization of other planets hasn't happened not because we don't have the tech or resources: we do! its just there's no good reason to, other than its a really really cool idea... overpopulation is certainly never going to be good reason to send a few hundred thousand people to mars or something: I mean, seriously, its much cheaper and easier, and more comfortable to go live in antarctica, or underwater colonies, or a nice bungalow in Reykjavik.
I don't think lightning is a very big deal if you've got the tech to build the floating city in the first place: lightning is an excellent source of power, as is wind: sure, hyperwinds are dangerous, but if you can harness *some* of that energy you're set! But those are extremely difficult to harness: by comparison, solid bodies have geothermic energy available, which for gas giant moons is a very viable possibility which you don't need futuretech to take advantage of: rocks are the kind of thing we've been doing R&D since forever to live on <I mean, there's literally never been anyone who has lived on a flying thing, as far as I know... seasickness sounds terrible>. Waterwords seem much more hospitable than gas giants, to me: i mean ships we know how to make [though what we would make them out *of* is a better question]. Its quite true that low-grav makes things different, but low grav is not no grav: 1/4 gravity is not something we know the effects of: maybe
But the most interesting resource that we could find in the solar system is biota: I mean, rocks are fine and all, but outside stuff like iridium <which, granted, is kind of expensive and *could* fund asteroid mining> there's not much stuff up there that isn't down here. But biota hace incredible economic value, and alien biota would probably have even more, since its so different. Europan fish would probably have amazing antifreeze in their blood, or this one molecule which could cure cancer... I mean, we already know penicilin, but what penicilins lie over there. Also, can you *imagine* how awesome it would be to have fish from europa in your living room? Plus, we could get them to work for us by giving them nice glass beads or something. xD
I don't think lightning is a very big deal if you've got the tech to build the floating city in the first place: lightning is an excellent source of power, as is wind: sure, hyperwinds are dangerous, but if you can harness *some* of that energy you're set! But those are extremely difficult to harness: by comparison, solid bodies have geothermic energy available, which for gas giant moons is a very viable possibility which you don't need futuretech to take advantage of: rocks are the kind of thing we've been doing R&D since forever to live on <I mean, there's literally never been anyone who has lived on a flying thing, as far as I know... seasickness sounds terrible>. Waterwords seem much more hospitable than gas giants, to me: i mean ships we know how to make [though what we would make them out *of* is a better question]. Its quite true that low-grav makes things different, but low grav is not no grav: 1/4 gravity is not something we know the effects of: maybe
But the most interesting resource that we could find in the solar system is biota: I mean, rocks are fine and all, but outside stuff like iridium <which, granted, is kind of expensive and *could* fund asteroid mining> there's not much stuff up there that isn't down here. But biota hace incredible economic value, and alien biota would probably have even more, since its so different. Europan fish would probably have amazing antifreeze in their blood, or this one molecule which could cure cancer... I mean, we already know penicilin, but what penicilins lie over there. Also, can you *imagine* how awesome it would be to have fish from europa in your living room? Plus, we could get them to work for us by giving them nice glass beads or something. xD
Re: Floating colonies above an ice giant
Torco, funny you mention fish on Europa, as it was me who was developing a language for Europian sharks.
Re: Floating colonies above an ice giant
Yeah, I remember them europan sharks. We will go harvest their livers and use them as the basis for a new, revolutionary treatment for erectile dysfunction 
Re: Floating colonies above an ice giant
You do that then.
Back to this thread though....
Back to this thread though....
Re: Floating colonies above an ice giant
I've decided to make this fantasty, rather than scifi now. Going to be islands flaoting high above an endless sea of lava.
Re: Floating colonies above an ice giant
Having thought on it a bit more, there might be some scientific hope for a 'doable scenario' on a miniature gas giant. These are a class of such planets that, due to being much smaller, wouldn't sport nearly as violent of atmospheres. Indeed, they might not form the hypervelocity bands of clouds that characterize the 'stripe-y' appearances of familiar giants like Jupiter and Saturn, having more 'earthy' cloud shapes (although still having no 'surface', of course). If you plop one of these in the habitable zone of a star and get some blimps going, perhaps it could work? The main caveat is that such a planet would be low-grav, unless you pulled some shenanigans on the planet's core composition.
In this kind of scenario, I could perhaps see a set of floating blimps being connected, and being able to dare walk through a windy gale of hydrogen and water vapor. The planet could shelter the inhabitants from radiation (atmosphere & magnetosphere) whilst not being so big as to be a major cause of irradiation. Going outside still strikes me as an incredibly bad idea, but might not rip your ligaments apart.
In this kind of scenario, I could perhaps see a set of floating blimps being connected, and being able to dare walk through a windy gale of hydrogen and water vapor. The planet could shelter the inhabitants from radiation (atmosphere & magnetosphere) whilst not being so big as to be a major cause of irradiation. Going outside still strikes me as an incredibly bad idea, but might not rip your ligaments apart.
Re: Floating colonies above an ice giant
This bit from Wikipedia could make it a bit difficult:Sakir wrote:Having thought on it a bit more, there might be some scientific hope for a 'doable scenario' on a miniature gas giant. These are a class of such planets that, due to being much smaller, wouldn't sport nearly as violent of atmospheres. Indeed, they might not form the hypervelocity bands of clouds that characterize the 'stripe-y' appearances of familiar giants like Jupiter and Saturn, having more 'earthy' cloud shapes (although still having no 'surface', of course). If you plop one of these in the habitable zone of a star and get some blimps going, perhaps it could work? The main caveat is that such a planet would be low-grav, unless you pulled some shenanigans on the planet's core composition.
In this kind of scenario, I could perhaps see a set of floating blimps being connected, and being able to dare walk through a windy gale of hydrogen and water vapor. The planet could shelter the inhabitants from radiation (atmosphere & magnetosphere) whilst not being so big as to be a major cause of irradiation. Going outside still strikes me as an incredibly bad idea, but might not rip your ligaments apart.
Several exoplanets have been discovered that are possibly gas dwarfs, based on known masses and densities. For example, Kepler-11f[1] has a mass of 2.3 Earth masses, yet its density is the same as that of Saturn, implying that it is a gas dwarf with a liquid ocean surrounded by a thick hydrogen–helium atmosphere and only a small rocky core. Such planets should not orbit too close to their parent stars, because otherwise their thick atmospheres would be blown away by stellar winds. It is demonstrated that the inner planets of the Kepler-11 system have higher densities than planets farther away.
You can tell the same lie a thousand times,
But it never gets any more true,
So close your eyes once more and once more believe
That they all still believe in you.
Just one time.
But it never gets any more true,
So close your eyes once more and once more believe
That they all still believe in you.
Just one time.
Re: Floating colonies above an ice giant
Indeed tricky. Although unlikely, perhaps the core of the gas dwarf could be super electric and deflect the majority of the wind? It's certainly a pretty slim scenario.This bit from Wikipedia could make it a bit difficult:
Several exoplanets have been discovered that are possibly gas dwarfs, based on known masses and densities. For example, Kepler-11f[1] has a mass of 2.3 Earth masses, yet its density is the same as that of Saturn, implying that it is a gas dwarf with a liquid ocean surrounded by a thick hydrogen–helium atmosphere and only a small rocky core. Such planets should not orbit too close to their parent stars, because otherwise their thick atmospheres would be blown away by stellar winds. It is demonstrated that the inner planets of the Kepler-11 system have higher densities than planets farther away.
[Edit]
Further, if we're going to get creative with the composition, the atmosphere could be thicker and made up of air rather than hydrogen. The higher mass of nitrogen and the like might make the atmosphere more durable, the hydrogen having been largely stripped away by the mentioned stellar wind.
Re: Floating colonies above an ice giant
Well maybe fiddling with the parent star could solve that? like, orbiting a brown giant that radiates heat but doesn't cast significant stellar wind, or maybe a blue star that's so luminous you have to stand quite away to not get broiled and so the wind isn't that significant ?
Re: Floating colonies above an ice giant
True, although I don't think such drastic changes need to be radioed in. One thing to consider is that it would seem incredibly unlikely for life that needed floating platforms & islands to evolve natively on our desired air giant: the more natural assumption might be that the habitats and denizens were placed there by colonists whose technological heritage was lost over time. If this is the case, we only need a million years or several thousand years of 'ehh, close enough' to place the entire prehistory, developmental, and modern/spaceborne periods of a conculture there. It may indeed be the case that the atmosphere would be shedded, but if the rate wasn't hyperbolic we might not need to care. If of interest, it might be fun to investigate how a culture deals with their atmosphere running away: perhaps they build great space arks, hahaTorco wrote:Well maybe fiddling with the parent star could solve that? like, orbiting a brown giant that radiates heat but doesn't cast significant stellar wind, or maybe a blue star that's so luminous you have to stand quite away to not get broiled and so the wind isn't that significant ?
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Salmoneus
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Re: Floating colonies above an ice giant
When did this become an endogenous civilisation?
Anyway, bigger question: what's the point? We already have Venus, which is effectively a gas world; ocean worlds are also likely to develop extremely thick atmospheres. So if you want floating cities, you don't have to assume specifically an ocean of liquid hydrogen below!
Anyway, bigger question: what's the point? We already have Venus, which is effectively a gas world; ocean worlds are also likely to develop extremely thick atmospheres. So if you want floating cities, you don't have to assume specifically an ocean of liquid hydrogen below!
Blog: [url]http://vacuouswastrel.wordpress.com/[/url]
But the river tripped on her by and by, lapping
as though her heart was brook: Why, why, why! Weh, O weh
I'se so silly to be flowing but I no canna stay!
But the river tripped on her by and by, lapping
as though her heart was brook: Why, why, why! Weh, O weh
I'se so silly to be flowing but I no canna stay!
Re: Floating colonies above an ice giant
Thanks for the replies guys, I think I will stick to fantasy, which is a cheat way of saying 'I can't do the science'