The Economics of Terraforming.

[GrandMasterTerwynn]

Wouldn't 20% methane in an oxygen atmosphere be easily ignited?

No. Methane only ignites when the concentration of gas is high enough to sustain combustion, but not so high that the combustion reaction finds methane molecules, and not enough oxygen molecules to complete the reaction. An atmosphere comprised of 20% methane is much too methane-enriched for it to easily ignite, or ignite at all. It's just like the fuel-air mixture in an automobile engine. Too lean, and the engine loses power. Too rich, and the engine floods.

Sure?
Remember, we're dealing with a low-gravity environment, where you'd likely have less total pressure, thus a higher relative amount of O2 to maintain the partial pressure necessary to make it breathable.
If you're "lucky", you might put the CH4/O2 relation right back into the explosive range

Not quite the way it works. For the greenhouse effect to supply habitable conditions, and for the partial pressure of oxygen to be enough to offset the amount of methane in the new atmosphere, we're talking about introducing enough atmospheric gas for a surface pressure of about 2.5 atmospheres.

[AMX]

Thanks.
Hmm...
Doesn't methane have this tendency to, y'know, float upwards?
Which could, given the right weather (read: no wind to keep stuff properly mixed), leave low areas (ditches, cellars, etc) with a decidedly lower than normal amount of methane.
Kinda like how CO2 tends to accumulate in wine cellars, only the other way round, and with more BLAM.

Hoping that's the last prob' in this direction I can think of...

[GrandMasterTerwynn]

Thanks.
Hmm...
Doesn't methane have this tendency to, y'know, float upwards?
Which could, given the right weather (read: no wind to keep stuff properly mixed), leave low areas (ditches, cellars, etc) with a decidedly lower than normal amount of methane.
Kinda like how CO2 tends to accumulate in wine cellars, only the other way round, and with more BLAM.

Hoping that's the last prob' in this direction I can think of...

This is a planet-sized mass of gas we're talking about here. Convective heating and cooling of the atmosphere, and winds generated by differences in temperature of the atmospheric air-masses would stir the atmosphere enough to keep everything well-mixed.

[Lord Zentei]

Yeah, about that. And you can only apply it so fast, lest you destroy the moon before you can get it somewhere useful. Might be better to find something in the Kuiper-belt with a long, slow orbit. Less kinetic energy to cancel out. However, slowing it down after the long fall into the solar system is going to be tricky, since you don't want something that big to hit Venus so hard that most of it, and a sizeable fraction of the planet to boot, ends up rebounding back into space.

Obviously. A Kuiper belt object randezvousing with a planet is not exactly a straightforward thing to accomplish, but perhaps the gradual thrust requirement is an advantage. Presumably a set of fusion engines plus mining equipment to extract some of the hydrogen from the ice would be used.

I suppose one would have to scoop as much of it up as possible, though getting in the way of a laser potent enough to drive off the atmosphere in human timescales might not be the brightest idea.

No indeed. Though I'm guessing here... the beam - or beams - need not be projected over the entire diameter. Given suitably accurate prior modeling of the heating, might the bulk of the CO2 be caused to be ejected along preferred paths?

In this scheme, atmospheric circulation will dictate that the CO2 will naturally settle at the poles, forming growing CO2 polar ice-caps.

Of course... sorry.

If one has an economic collapse deep enough and long enough that it lasts past the time the mirror system will remain stable on its own, then one probably has much bigger problems to worry about than the fate of some unlucky Venusian colonists.

Yes, but the question I was considering was whether these colonization efforts could be used as an insurance policy for humanity. If the colonies will always be dependant on active systems to avoid complete extinction, then they won't serve ideally in that purpose. It would be that the Earth was the Colonies' insurance instead.

Heck, the terraforming laser will probably be a threat to most everything in the Solar System that's within the laser's field of view.

Sadly true. Perhaps an intrinsic flaw could be built into the structure such that the range will always be limited. Sort of a deliberate Hubble screw-up.

OK how's this: we have H in the regolith and CO2 in the atmosphere. We also have a big-ass mirror and laser. Would it be feasible to use the mirror to do the following:

1) Lower the temperature to Earth levels.
2) Power immense electrolysis machines that sift the C from the O2 in the atmosphere.
3) Power H2 harvesters that mine the regolith.

Burn the extracted H2 with the O2 and dump the C in designated areas.

This would probably be feasible, but only after you reduce the surface atmospheric pressure to levels that are slightly less lethal to equipment. Or design complex equipment to operate for decades or centuries under up to 90 atmospheres of pressure.

Yes, and ungodly temperatures. Overall, though I can't help but feel that this would be more palatable than the boiling away method, and more doable perhaps than moving Pluto.

Actually, we're going to want to aggressively scrub the smog from the atmosphere. Like the photochemical smog on Titan, the smog on our terraformed Jovian moon will dampen the greeenhouse effect if you allow enough of it to accumulate.

Of course, though I was considering the speed of the process, and how complete it could be made.

And methane's potency as a greenhouse gas is why I picked it. It's relatively easy to obtain or manufacture (compared to exotic CFCs) and it isn't toxic or corrosive like large quantities of CO2 or ammonia would be.

Yes, but you are sure 20% methane is a-ok? I mean for lifespan durations?

[AMX]

Thanks.
Hmm...
Doesn't methane have this tendency to, y'know, float upwards?
Which could, given the right weather (read: no wind to keep stuff properly mixed), leave low areas (ditches, cellars, etc) with a decidedly lower than normal amount of methane.
Kinda like how CO2 tends to accumulate in wine cellars, only the other way round, and with more BLAM.

Hoping that's the last prob' in this direction I can think of...

This is a planet-sized mass of gas we're talking about here. Convective heating and cooling of the atmosphere, and winds generated by differences in temperature of the atmospheric air-masses would stir the atmosphere enough to keep everything well-mixed.

You *are* aware that I moved from "accidentally igniting the entire atmosphere" down to "and what if my basement blows up"?
You know, just because the atmosphere as a whole is properly mixed doesn't mean there won't be local "un-mixing" events; especially in areas protected from weather (such as the aforementioned basement).

[GrandMasterTerwynn]

Yeah, about that. And you can only apply it so fast, lest you destroy the moon before you can get it somewhere useful. Might be better to find something in the Kuiper-belt with a long, slow orbit. Less kinetic energy to cancel out. However, slowing it down after the long fall into the solar system is going to be tricky, since you don't want something that big to hit Venus so hard that most of it, and a sizeable fraction of the planet to boot, ends up rebounding back into space.

Obviously. A Kuiper belt object randezvousing with a planet is not exactly a straightforward thing to accomplish, but perhaps the gradual thrust requirement is an advantage. Presumably a set of fusion engines plus mining equipment to extract some of the hydrogen from the ice would be used.

That would work. Venus terraformers should be okay as long as most of the KBO gets to where it's going. If it doesn't, the Kuiper belt is packed with hundreds of large bodies of ice.

I suppose one would have to scoop as much of it up as possible, though getting in the way of a laser potent enough to drive off the atmosphere in human timescales might not be the brightest idea.

No indeed. Though I'm guessing here... the beam - or beams - need not be projected over the entire diameter. Given suitably accurate prior modeling of the heating, might the bulk of the CO2 be caused to be ejected along preferred paths?

True. Focusing the beam would be preferrable, especially if you were using a combination of methods to pull off the atmosphere.

If one has an economic collapse deep enough and long enough that it lasts past the time the mirror system will remain stable on its own, then one probably has much bigger problems to worry about than the fate of some unlucky Venusian colonists.

Yes, but the question I was considering was whether these colonization efforts could be used as an insurance policy for humanity. If the colonies will always be dependant on active systems to avoid complete extinction, then they won't serve ideally in that purpose. It would be that the Earth was the Colonies' insurance instead.

In an ideal situation, the colonies would grow to the point where they'd be able to field their own native-instructed terraforming engineers who could take on the task of performing their own maintenance on the equipment. You could, if you had complex autonomous machines and sophisticated AIs laying about, have the mirrors take care of themselves, and stay in some default maintenance state if solar civilization went back to the Stone Age. This sort of automation should be well within the grasp of any interplanetary civilization willing to engage in wholesale planetary engineering.

This would probably be feasible, but only after you reduce the surface atmospheric pressure to levels that are slightly less lethal to equipment. Or design complex equipment to operate for decades or centuries under up to 90 atmospheres of pressure.

Yes, and ungodly temperatures. Overall, though I can't help but feel that this would be more palatable than the boiling away method, and more doable perhaps than moving Pluto.

It would probably also be a bit more profitable too. Though Venus would have to generate a lot of surplus carbon to be competitive (Unlike Mars and Earth, Venus doesn't rotate fast enough to support an orbital elevator,) though with the size of the planet's carbon stores, this won't be a problem.

Actually, we're going to want to aggressively scrub the smog from the atmosphere. Like the photochemical smog on Titan, the smog on our terraformed Jovian moon will dampen the greeenhouse effect if you allow enough of it to accumulate.

Of course, though I was considering the speed of the process, and how complete it could be made.

On an atmosphere as thick as the one proposed here, you could support cyanobacteria dust fairly far up into the atmosphere. There would be a considerable volume of the it to work with, and it would stay aloft for long periods of time, be well-mixed, and enjoy global coverage, since the atmospheric dynamics will be like Titan's (that is, the upper layers of the atmosphere rotate much faster than the parent world does.)

And methane's potency as a greenhouse gas is why I picked it. It's relatively easy to obtain or manufacture (compared to exotic CFCs) and it isn't toxic or corrosive like large quantities of CO2 or ammonia would be.

Yes, but you are sure 20% methane is a-ok? I mean for lifespan durations?

Methane is biologically inert. Packing the bloodstream with it seems to do nothing to the blood's ability to carry oxygen, and at high enough concentrations it seems to have anesthetic properties (At around three atmospheres, half of mice exposed to it don't develop convulsions from electroshock therapy, but we're proposing using no more than four-tenths to three-quarters of an atmosphere (depending on atmospheric thickness,)) but doesn't cause suffocation, provided abundant oxygen is present. You could attenuate the amount of methane needed by using small amounts of ammonia and artificial CFCs, though you don't want atmospheric methane to be less than 15%, otherwise the resultant mix becomes rather explosive.

[GrandMasterTerwynn]

Thanks.
Hmm...
Doesn't methane have this tendency to, y'know, float upwards?
Which could, given the right weather (read: no wind to keep stuff properly mixed), leave low areas (ditches, cellars, etc) with a decidedly lower than normal amount of methane.
Kinda like how CO2 tends to accumulate in wine cellars, only the other way round, and with more BLAM.

Hoping that's the last prob' in this direction I can think of...

This is a planet-sized mass of gas we're talking about here. Convective heating and cooling of the atmosphere, and winds generated by differences in temperature of the atmospheric air-masses would stir the atmosphere enough to keep everything well-mixed.

You *are* aware that I moved from "accidentally igniting the entire atmosphere" down to "and what if my basement blows up"?
You know, just because the atmosphere as a whole is properly mixed doesn't mean there won't be local "un-mixing" events; especially in areas protected from weather (such as the aforementioned basement).

This can be addressed one of two ways. First is to seal the houses and provide an internal methane-poor atmosphere. Failing that, you specify rigorous building codes and require that a building be well-ventilated (one would probably want to heat the air first, though, since the temperatures in the tropics won't get much above fifty degrees farenheit (10 degrees centigrade.)

[CoyoteNature]

What about creating a belief structure?

They last quite a bit longer then governments, businesses, or nearly anything else. It would also allow for the terraforming to be accomplished despite changes to Solar Civilization.

Not that they last forever, but Christianity lasted 2000 years, Judaism even longer. It is a very effective meme, curious if you couldn't create a similar meme to tend the terraforming.

[Surlethe]

What about creating a belief structure?

They last quite a bit longer then governments, businesses, or nearly anything else. It would also allow for the terraforming to be accomplished despite changes to Solar Civilization.

Not that they last forever, but Christianity lasted 2000 years, Judaism even longer. It is a very effective meme, curious if you couldn't create a similar meme to tend the terraforming.

As done in Dune? Pardot Kynes managed to take the Fremen mythos and twist it so the Fremen were ultimately dedicated to the transformation of Dune into a jungle planet (as seen in God-Emperor), though it took several millennia.

[CoyoteNature]

Yes basically, it just seems that if you are going to engineer planets, you might have to engineer the society too so that it lasts long enough to continue it.

[GrandMasterTerwynn]

Yes basically, it just seems that if you are going to engineer planets, you might have to engineer the society too so that it lasts long enough to continue it.

Except religions tend to carry with them the substantial risk of becoming fixed and dogmatic, which is something you don't want to saddle an engineering and scientific endeavour with, unless your civilization is sufficiently advanced that your terraforming projects can survive the equivalent of a slide into the Dark Ages.

[CoyoteNature]

They do become fixed and dogmatic, but it doesn't mean they can't use new technologies and science from outside their framework.

Or only apply technology and science as it applies to their own very limited goals, i.e. terraforming.

I mean look at the current day fundamentalists, even those in the science field, they use advanced technology and science every day, but through some peculiar mental gymnastics still manage to ignore the foundations of said thing.

There are even some biologists who completely disregard evolution, even when dealing with the evolution of new viruses and bacteria.

Also you don't necessarily have to reorganize all of society, only enough of it to matter towards terraforming. The rest of society can continue on towards scientific innovation, or whatever other cultural goals they might have, or even indeed falling back into the stone age.

[GrandMasterTerwynn]

They do become fixed and dogmatic, but it doesn't mean they can't use new technologies and science from outside their framework.

Or only apply technology and science as it applies to their own very limited goals, i.e. terraforming.

I mean look at the current day fundamentalists, even those in the science field, they use advanced technology and science every day, but through some peculiar mental gymnastics still manage to ignore the foundations of said thing.

There are even some biologists who completely disregard evolution, even when dealing with the evolution of new viruses and bacteria.

Also you don't necessarily have to reorganize all of society, only enough of it to matter towards terraforming. The rest of society can continue on towards scientific innovation, or whatever other cultural goals they might have, or even indeed falling back into the stone age.

You shouldn't need to develop an organized religion which worships terraforming, though. It is arguable that any civilization capable of even attempting the sorts of enormous engineering projects necessary to terraform a world otherwise unsuitable for our sort of life will probably stick around long enough to see the job done. (As one might be able to see from the discussions in this thread, terraforming requires a huge investment of time and resources. It cannot be taken up lightly and dropped at a whim. Especially as some of the schemes demand the construction of giant lasers which could be used as motivation to keep the project on track. )