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#1 2011-11-29 15:22:39

Terraformer
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From: Logres
Registered: 2007-08-27
Posts: 3,363
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Hybrid Worldhouse

This is a post that I made a while back, before the crash - since there's no knowing when it may come back, I thought I'd repost it; replies can always be merged later.
_________________________________

I'm developing this concept for usage on dwarf planets, although it may find use on larger bodies by groups wishing for rapid terraforming. It is essentially an extension of the practice of "tenting" an area on a world with a thick atmosphere, to allow for a breathable atmosphere within, in the same way that a normal worldhouse is an extension of domed colonies.

One of the issues that a worldhouse faces, in fact the biggest issue, is it's vulnerability to impactors - even a small impactor can blast a hole in the roof, allowing the air to escape and possibly prompting catastrophic failure of the roof. A good defence system can deal with this, but as Chris McKay say, it misses the point - a terraformed planet should not be high maintaince, failing in a few years if it's inhabitants stop repairing it's systems. On the other hand, a 'natual' terraformed moon or dwarf planet requires a lot of gas, which presents the problems of sourcing it, though this is minor to the problem of atmospheric escape.

So I propose we combine the two approaches: use a worldhouse, but with an atmosphere on top. The atmosphere can be much thinner than the interior one, although it has to be thick enough to stop most impactors (if it's the equivelent of a Chixiculub, it does't matter if the planets a worldhouse or not, since it's practically unsurvivable anyway). It should be able to survive for, on average, several thousand years at the least without maintainence. If we design it correctly, I see no reason why it wouldn't - the pyramids have lasted that time. It's probably best to keep the exterior pressure slightly lower than the interior pressure, so that any leaks would result in a slight pressure outwards, not enough to cause a significant about of loss but enough to keep the interior habitable long enough.

It also has the advantage of allowing the greenhouse properties of each world to be customized, removing the need for large reflectors in orbit.


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#2 2011-11-29 15:26:22

Terraformer
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From: Logres
Registered: 2007-08-27
Posts: 3,363
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Re: Hybrid Worldhouse

BTW, I was envisioning the outer atmosphere being of a different, and denser, gas - for example, while the interior temperature would be above freezing, the outer atmosphere would be at Titan level temperatures, resulting in a denser atmosphere. It could be made of anything; closer in we might use CO2, simply because it's dense and available.


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#3 2012-02-08 15:57:31

Terraformer
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From: Logres
Registered: 2007-08-27
Posts: 3,363
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Re: Hybrid Worldhouse

For smaller worlds, such as dwarf planets, the outer atmosphere is likely to be at a significantly lower pressure than the inner atmosphere, under the shell. However, I still think this is a good idea - the outer atmosphere will provide radiation and meteorite protection, allowing the worldhouse to last without active maintenance. If we could engineer the ability to fix itself into the layer, it could potentially last millenia without intervention, until some fool puts a rocket through it after society has been rebuilt...


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#4 2012-02-09 13:39:14

karov
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From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Hybrid Worldhouse

Terraformer,

"Active SELF-maintenance" is the trick for anything to last long.

I think a combination of Utility Fog and Weather Machine will do the job you mean best. http://en.wikipedia.org/wiki/J._Storrs_Hall

The aerostat-lets provided with flagella which serve as also interlocking arms. The ultimate conditioner controlling completely the incomming and outgoing traffic of :: light, radiation, heat exchange, molecules, space ships ... everything.

Such foamy membrane can never puncture, it self-heals, self-replicates its cells - powered by the sun and using as construction materials the atmosphere itself.

It may maintain 300k temp range underneath itself, while above there is super-cold , super-dense gaseous envelope. The membrane can activelly move air up-down and thus cooling artificially the upper layer.

The super-thermal barrier will be also ultimate water trap, and the supercold upper layer will be subject of far lesser air dissipation. Keep the exosphere of even as small body as Vesta, Ceres, Hygeia, Palas around 20-30k and the fluids around the body will not evaporate for millions of years.

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#5 2012-02-09 15:19:56

Terraformer
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From: Logres
Registered: 2007-08-27
Posts: 3,363
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Re: Hybrid Worldhouse

I'm rather wary of active systems. I think, if we can colonise the initial roof with suitable bacteria, we might be able to make it self-maintaining, and that's good enough for me. We'll need some way as well to ensure punctures don't destroy the hole structure, but that might be possible to make an inherent feature of the design (a framework with plates covering each hectare of material, or even better every square meter, possibly? If a plate blows, it can be replaced without destroying the entire structure). We might need some kind of equivalent of platelets, which will wedge in any damaged areas....

It is rather difficult to build a suitable roof, indeed. I think we're actually going to have to go with the foamy idea, which I did think about before as a possible solution... say, if we can make suitable transparent (in the visible spectrum) self-replicating lifeforms, which can bind together with enough strength to form the roof... hmmm...


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#6 2012-02-10 05:58:52

karov
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From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Hybrid Worldhouse

with Storrs's style bubble-lets you cover each and every square MILIMETRE, and not only once but thousands of times.

The bubblets serve vast multitude of functions -- they not only let in light, but do it in controled manner -- they control the photonic input by :: direction, frequency, phase ... and not only the input, but control the otbound IR photons, too. The planet turns into giant laser, tv screen, telescope, antenna... even the smallest incomming meteoroid may be intercepted and evaporated on the appropriate hight so its mass to be swallowed and utilized into the system.

The foamy structure of bubblets with flagella-arms may form very robust, high tensiole strenght material, and this material is not static but closes gaps, opens quickly when needed.

The Weather Cloud also produces mag field when needed and interacts with the interplanetary plasmic environment.

It works on nanometer wavelenghts, hence it provides also ( as a side product / effect ) hyper-broadband communcation within itself and around the world. Recent visible light wi-fi systems readily achieve hundreds of Gb speed.

If we asign ant-size brain to each bubblet ( Storrs envisions they to be between 1mm to 1 cm ), than the total swarm would comprise super-AI, too. Of course we do not need personality, but super-powerfull adaptive handler, tuned intrinsically to provide living environment for baseline humans ...

The Cloud is also, as I said giant airconditioner -- 300k beneath / 30k on top.

The easiest way is to make the bubble-lets self-replicating or at least assembling into replicators.

Thus the target planet could be "infected" with a Cloud seed massing only grams, which step by step to blow up planetary covering bubble-of-bubbles.

The Cloud will represent the next evolutionary level. In 1970es they called it Macro-life. The same way the standard biosphere is ensemble of self-replicating organisms, comprised of self-replicating cells ... The Cloud will be self-replicating biosphere...

ref.s.:

http://nextbigfuture.com/2008/12/nanote … l-and.html

http://nextbigfuture.com/2011/09/kardas … gfuture%29

Quote::

"
Hall Weather Machine



A far better architecture for capturing the solar energy that hits the earth is the Hall weather machine.

The Hall Weather Machine is a thin global cloud consisting of small transparent balloons that can be thought of as a programmable and reversible greenhouse gas because it shades or reflects the amount of sunlight that hits the upper stratosphere. These balloons are each between a millimeter and a centimeter in diameter, made of a few-nanometer thick diamondoid membrane. Each balloon is filled with hydrogen to enable it to float at an altitude of 60,000 to 100,000 feet, high above the clouds. It is bisected by an adjustable sheet, and also includes solar cells, a small computer, a GPS receiver to keep track of its location, and an actuator to occasionally (and relatively slowly) move the bisecting membrane between vertical and horizontal orientations. Just like with a regular high-altitude balloon, the heavier control and energy storage systems would be on the bottom of the balloon to automatically set the vertical axis without requiring any energy. The balloon would also have a water vapor/hydrogen generator system for altitude control, giving it the same directional navigation properties that an ordinary hot-air balloon has when it changes altitudes to take advantage of different wind directions at different altitudes.

By controlling a tenth of one percent of solar radiation is enough to force global climate in any direction we want. One percent is enough to change regional climate, and ten percent is enough for serious weather control.

The surface are of the earth is 510 trillion square meters.

So getting to 0.1% coverage is 510 billion square meters.

There is mylar that is 2 microns thick and weighs about 2.4 grams per square meter. Office Paper is usually 80 grams per square meter.

There is plastic sheeting with 0.3-0.9 micron thickness and weights of 0.54 to 1.2 grams per square meter.

US plastic film demand was expected to be about 7.3 million tons in 2012

So if you could achieve large scale production (equal to 1% of total US plastic film production in 2012) of 1 gram per square meter balloon sheeting with a diamond surface treatment and the other parts of the system there would be 73,000 tons of weather machine produced. This would cover 73 billion square meters. In about 8 years, one would be able to produce a 1% coverage Hall Weather Machine.

The production system would be a more advanced version of bubble wrap production. Each bubble would be functionalized and perhaps laser cut into separate balloons. Rapid printable electronics would probably be the best way to get the solar cell and GPS components into the bubble/balloon. The printable electronics would need to be scanned onto the surface of the sheet, before the top layer is attached.

With better than todays nanotechnology one could easily produce a more advanced version of the hall weather machine. It is a weather machine and a means to use not that much material to get to Kardashev level one.

Mark I and Mark II weather machines.

Weather machine Mark I - many small aerostats—a hydrogen balloon—at a guess an optimal size is somewhere between a millimeter and a centimeter in diameter that have a continuous layer in the stratosphere. Each aerostat contains a mirror, and also a control unit consisting of a radio receiver, computer, and GPS receiver. About 100 billion tonnes of material with regular technology and 10 million tons with more advanced nanotechnology.

Once you are approaching kardashev level one or even at ten times the current world economy then funding a true space industry in the solar system is trivial

If your nanotechnology is at this level then making spaceships and sending nanofactories to Venus and asteroids would be relatively simple. It would be about twenty million tons of material for the mirror bubbles and converters for each earth scale energy system. Then the electricity has to be transmitted and distributed to where it needs to be used (a super-grid which could be wireless)

Two billion of those systems turns humanity into a Kardashev Type II civilization.

Producing large bubbles in space is something that looks very doable.
The bubbles would be set up to focus solar energy to make the collection of solar power easier.

The most interesting Nasa Institute Advanced Concepts (NIAC) study released from the March 2007 meeting is Devon Crowe of PSI corporation for making large space structures from bubbles that are made rigid using metals or UV curing.

A single bubble can be 1 meter in earth gravity, 100 kilometer in low earth orbit or 1000 kilometers in deep space. Foams made of many bubbles could be far larger in size.

Metal can be evaporated to coat the inside of the bubble for reflective sails and telescopes.

I also think that GDP growth will get faster. So we will get to (or need to get to) Kardashev level one and level two far sooner than your 2.3% projection.

I have also covered Dyson swarms and Dyson Spheres
"

Last edited by karov (2012-02-10 06:04:04)

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#7 2012-04-05 08:06:38

Terraformer
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From: Logres
Registered: 2007-08-27
Posts: 3,363
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Re: Hybrid Worldhouse

Hmmm. What happens if the system is left alone for a few decades, with no maintanence? What about a few centuries?

I don't like to discuss terraforming that we can't do with current technology and understanding, either...

Perhaps we could introduce a biofilm of plastic producing bacteria into the mix, to maintain but not repair the roof, perhaps using materials gathered from the outer atmosphere?

We might want to use several, or several dozen, layers. Say, we'll go from 300mb to 290mb and so on, all the way down to 50mb, increasing redundency and potentially allowing energy to be successively concentrated down to the surface - maybe the outer layer will fluoresce under X-rays to give UV, and the layer below that will give red etc.

Now, as for the oscillations of such a system...


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#8 2012-04-06 13:23:04

karov
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From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Hybrid Worldhouse

Terraformer wrote:

Hmmm. What happens if the system is left alone for a few decades, with no maintanence? What about a few centuries?

I don't like to discuss terraforming that we can't do with current technology and understanding, either...

Terraformer,

Well, does self-maintenance ( + error correction to avoid "mutation" and cancer-like developments ) qualify as maintenance? I think yes. Especially if the self-maintaining system energetically feed upon the forces which try to destroy it.

On my understanding such system belong to current level of tech. NO unknown physics, etc. It is kinda clanking replicator tech, sorta "synthetic biology".

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#9 2012-04-18 22:15:37

Void
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Registered: 2011-12-29
Posts: 3,927

Re: Hybrid Worldhouse

Quote and also not ignoring Karov at all:

Hmmm. What happens if the system is left alone for a few decades, with no maintanence? What about a few centuries?

I don't like to discuss terraforming that we can't do with current technology and understanding, either...

Perhaps we could introduce a biofilm of plastic producing bacteria into the mix, to maintain but not repair the roof, perhaps using materials gathered from the outer atmosphere?

We might want to use several, or several dozen, layers. Say, we'll go from 300mb to 290mb and so on, all the way down to 50mb, increasing redundency and potentially allowing energy to be successively concentrated down to the surface - maybe the outer layer will fluoresce under X-rays to give UV, and the layer below that will give red etc.

Now, as for the oscillations of such a system...

I say what I will say not to reject what you concieve, but rather to make a compairison.  I am actually interested in your ideas more than mine, but I guess if I come to the table I should try to offer something.

I see Titan as the first in a line of worlds that might employ something like a world-house.  In the case of Titan, for my tastes I would modify it to be a bunch of very large bubbles on stilts.  Titan is childs play compaired to things further out.

Pluto, should it be desired, could be warmed up some more, perhaps with some method, and so might end up with an atmposphere like Titan's (Somewhat).

Further out it gets harder.

I could imagine for instance a rogue planet with a Hydrogen/Helium upper atmosphere and a Nitrogen lower atmosphere, and then you could do a world house for  that.  But I am not sure that rarified Hydrogen/Helium would provide enough insulation for the upper Nitrogen to maintain a vapor state.  Perhaps if it was helium and you had the Hall bubbles with Hydrogen in them?  Karov?

I guess a culture with fusion might generate Helium or collect it from interstellar space.



Close to the sun at all, however, and it would


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#10 2012-04-19 05:44:14

Terraformer
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From: Logres
Registered: 2007-08-27
Posts: 3,363
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Re: Hybrid Worldhouse

Given the amount of time it would take to reach the point where the entire atmosphere is oxygenated, I reckon we'll see hybrid worldhouses on any body that is terraformed, even if they don't need it to retain an atmosphere (Mars for example). Free Oxygen is rare, CO2, N2, Ammonia etc are comparatively abundant. We're going to be limited to building oxygenated habitats for the next few centuries at least without magitech, so we might as well cover the entire surface with them.

Titan is probably one of the easiest to terraform. Once you've dealt with the petrochemicals and warmed the place up a bit, UV radiation should be able to break down water to produce OH- radicals, which should clear the atmosphere of it's toxic chemicals. Then it's a case of roofing the entire world, perhaps using the hydrocarbons in the roofs manufacture, and heating the world below to something more habitable (~-20c?) and working out how to make the hydrocycle operate properly at such low temperatures...

For the Plutoids, getting to the Nitrogen atmosphere is the first step. No need to mess around with Hydrogen or Helium. Once you've got that, just roof the place and oxygenate underneath the roof. In such cold environments, the atmosphere should be stable, and you're looking at a much more reasonable amount of Oxygen, since the Nitrogen is providing all the pressure. Hopefully, waste heat from the world below would be enough to keep the outer atmosphere from freezing out.

I'm just not that certain about the mechanics of such a system. The roof might need to be anchored to the planet to stop dangerous oscillations.

Now, how about an Oort cloud that is absolutely covered with such worlds, which are maybe 100AU apart? Binaries seem quite common... it's quite easy to imagine a setting where there are thousands of habitable worlds, and empires that are a 1000AU in diameter, linked by torchship. Hundreds of different interstellar civilisations, fighting, trading, and building. The small gene pools would seem conducive to subspeciation, especially if mutants settle such worlds after being driven from the core worlds - a Terran traveler, several hundred years hence, may find themselves on many a planet, with beings that are at least as alien as any you might find in Star [Trek/Wars, delete according to preference]. Perhaps our interstellar future is with worlds and aliens of our own making.


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#11 2012-04-19 19:06:23

Void
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Re: Hybrid Worldhouse

Wow, I think I fell asleep last time.

Anyway, I know that your work is in progress, but how do you keep the Nitrogen from condensing on the hall bubbles?  Don't they have to float on something?


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#12 2012-04-20 03:00:50

Terraformer
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From: Logres
Registered: 2007-08-27
Posts: 3,363
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Re: Hybrid Worldhouse

Are you directing that question at me, or karov? I don't propose using Hall bubbles.

The trick to stopping condensation is to keep the temperature high enough. If we can maintain Titan level temperatures above the roof, it's easily high enough.


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#13 2012-04-20 14:33:42

Void
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Registered: 2011-12-29
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Re: Hybrid Worldhouse

Yes,  thanks. That is still a lot of energy leaking into space, but I am sure at some point it could become childs play to do, persuming continuing advancements in technology.


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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