What To Do With Venus?

[Broomstick]

There have been prior threads about terraforming Venus and the consensus seems to be that while it might be technically feasible it's not really cost-effective and there are a lot easier places to make habitable in the solar system.

Fine. Meanwhile, we have a very hot rock wrapped in sulfuric acid clouds. Can we do anything useful or nifty with this? So... the purpose of this thread is to come up with ideas for utilizing Venus as a resource. It doesn't matter if the end result is human-habitable or not, the game is to "mine" the planet for either fun or profit.

Starting with the atmosphere - well, if you want sulfuric acid there it is. In addition, lots of carbon dioxide. Rig up some solar power and you can get pure sulfur, carbon, and oxygen through various processes. Even trace gasses will be present in significant amounts just because there is just so damn much atmosphere.

Other than that, though - what else can be done with Venus?

[Iroscato]

Not quite answering your question, but...I'm fairly sure some parts of the upper atmosphere might actually be habitable - similiar temperature and pressure to that of Earth's surface. It may be feasible to construct a permanently floating habitat station to support colonists or any potential miners assuming there's anything useful on or under the surface/atmosphere.

[Broomstick]

I suppose it would make sense to park your atmosphere extractors on floating habitats of some sort, but you'd have to remember the atmosphere, even if the pressure is similar to Earth's, is not chemically the same. You could probably extract any needed oxygen, there is sufficient nitrogen to supply a non-toxic component for a safe breathing gas, crack some of the gasses to get hydrogen, bake your own water, but opening a window for some fresh air would be fatal.

[Iroscato]

I suppose it would make sense to park your atmosphere extractors on floating habitats of some sort, but you'd have to remember the atmosphere, even if the pressure is similar to Earth's, is not chemically the same. You could probably extract any needed oxygen, there is sufficient nitrogen to supply a non-toxic component for a safe breathing gas, crack some of the gasses to get hydrogen, bake your own water, but opening a window for some fresh air would be fatal.

Forgive my shocking display of wild guesswork, but could there a way to extract CO2 from the atmosphere, helping to grow plant life in such a habitat? That could help maintain a healthy, breathable environment inside. Or not. I really am shooting in the dark here

[Broomstick]

Sure, extracting CO2 should be easy. Heck we extract it from Earth's atmosphere to make dry ice and the CO2 of Earth's atmosphere is ridiculously small compared to Venus' (0.04% for Earth, 96% for Venus). The tricky bit is that you can't have that much CO2 if you want mammals like us to survive. At 1% effects can start to show up, 5% CO2 is fatal to humans.

What we need to be extracting is O2 and nitrogen. Just stick some animals on the habitat and they'll make plenty of CO2 for plants.

[PainRack]

Sulphuric acid itself is a useful industrial agent. However, I suspect any civilization able to provide enough power to make extracting it from Venus profitable has enough power to just make it here on earth.

[Crossroads Inc.]

It's been a while since I read the book, but didn't they "terraform" Venus in the book "3001" by hurling several hundred ice comets at it?

If I recall, the process was for the water to soak up the CO2 to the point where it was safe to land equipment. And then they built machines to filter out the CO2 from the water and extracted the carbon from it, venting the Oxygen back into the air?

[InsaneTD]

Yep. They wrapped the comets in a foil wrap so it doesn't melt, then push it towards the sun. Another tug catches it closer to Venus and adjusts the trajectory for a "soft" touchdown/burn up as it enters the atmosphere. The comets melting in the atmosphere were supposed to cool it.

[Borgholio]

There are no resources on Venus that are not easier to find or make right here on Earth. We don't need sulfuric acid so much that we have to go to Venus to get some. Venus would be very useful as a breadbasket though, or a place to colonize to help with overcrowding Earth. The issue is the temperature and the pressure on the surface. Many theories revolve around the idea of giant floating cities in the habitable altitudes, and that is probably the best idea. The only issue will be the kind of technology to keep these cities floating. If that can be managed, then you can have human settlements and massive greenhouses. The plants will gradually soak up the CO2 and lower the temperature of the planet, causing all the water and nasty stuff to rain out of sky and form oceans. The sulfuric acid will be consumed by the rocks and minerals on the surface until you are left with water that is sutable for primitive algae and phytoplankton to be introduced to the oceans. Meanwhile, there should be rain that actually hits the surface, so fast-growing land plants could be introduced.

When all is said and done, you have a planet that is a bit warmer than earth with a thicker atmosphere, but still has an ecosystem that is tolerable for humans...and given the increased level of sunlight, it will be very good for farming.

[madd0ct0r]

I was wondering about going the other way - shrouding venus with orbital mirrors. With less energy going in, the atmospheric heat will drop until a new equilibrium is struck.

let the C02 freeze out of the atmosphere, box it up (lol) and remove the mirrors. slowly add CO2 back as the plants grow. If a space elevator is possible, shipping co2 to mars sounds nice.

[Broomstick]

When all is said and done, you have a planet that is a bit warmer than earth with a thicker atmosphere, but still has an ecosystem that is tolerable for humans...and given the increased level of sunlight, it will be very good for farming.

I just don't think plants will make a dent in that atmosphere, nevermind the sulfuric acid. On Earth, most of the CO2 was soaked up via chemical reactions involving liquid water which, under present conditions, simply can't exist on Venus. Then life locked up the carbon already dissolved in the oceans.

Remember, we are talking about a planet where lead is a liquid on the surface.

First, you'd have to reduce the temperature of the place to below the boiling point of water. That means either siphoning off most of the atmosphere, or blocking the sunlight, or both. If you could colonize the upper atmosphere with some sort of algae any water produced would vaporize long before it reached the surface, would not dissolve CO2, and would not chemically lock up the gas so it would stop doing the greenhouse thing.

Even if you could use genetically engineered life to work that sort of thing the time scale involved would be geological. It just doesn't make sense.

[Broomstick]

I was wondering about going the other way - shrouding venus with orbital mirrors. With less energy going in, the atmospheric heat will drop until a new equilibrium is struck.

I think that's likely the most practical way to terraform it - even then, you'd probably have next to no water. I suppose you could lob some iceball comets at it, but then you have to worry about heating everything up again from the impacts.

You'd still have an insanely long day/night cycle with, I think, 2 rotations of Venus for every 3 trips around the sun, or maybe it's 3 days for every 2 Venusian years - I forget which way it falls, but that's the ratio. Also, little to no magnetic field. Also, instead of plate tectonics you just have the surface melt and turn over every 500 million years or so, very inconvenient if you are living there at the time.

You'd probably find it easier to terraform the Moon.

let the C02 freeze out of the atmosphere, box it up (lol) and remove the mirrors. slowly add CO2 back as the plants grow. If a space elevator is possible, shipping co2 to mars sounds nice.

That might work out on some level, except Mars has no magnetic field so the solar winds will eventually strip away atmosphere and you'll lack that protection from radiation

[Borgholio]

When all is said and done, you have a planet that is a bit warmer than earth with a thicker atmosphere, but still has an ecosystem that is tolerable for humans...and given the increased level of sunlight, it will be very good for farming.

I just don't think plants will make a dent in that atmosphere, nevermind the sulfuric acid. On Earth, most of the CO2 was soaked up via chemical reactions involving liquid water which, under present conditions, simply can't exist on Venus. Then life locked up the carbon already dissolved in the oceans.

Remember, we are talking about a planet where lead is a liquid on the surface.

First, you'd have to reduce the temperature of the place to below the boiling point of water. That means either siphoning off most of the atmosphere, or blocking the sunlight, or both. If you could colonize the upper atmosphere with some sort of algae any water produced would vaporize long before it reached the surface, would not dissolve CO2, and would not chemically lock up the gas so it would stop doing the greenhouse thing.

Even if you could use genetically engineered life to work that sort of thing the time scale involved would be geological. It just doesn't make sense.

I never said it would be quick. It would take a great deal of time for plants to make a dent in the air, that's true. If you wanted it done within a few human lifetimes, then you'd need a more drastic way such as blocking all sunlight from reaching the surface to cool it down, then find some way to keep the carbon from re-vaporizing and starting the greenhouse process all over again.

[madd0ct0r]

for anyone else playing along at home, here's a nice study from NASA http://ntrs.nasa.gov/archive/nasa/casi. ... 067857.pdf

There's a very illuminating pressure at altitude chart at the end.

[Broomstick]

I never said it would be quick. It would take a great deal of time for plants to make a dent in the air, that's true. If you wanted it done within a few human lifetimes, then you'd need a more drastic way such as blocking all sunlight from reaching the surface to cool it down, then find some way to keep the carbon from re-vaporizing and starting the greenhouse process all over again.

Well, yeah, except I never said I wanted to terraform it, I wanted to find a USE for Venus, like mining the atmosphere.

[Purple]

I never said it would be quick. It would take a great deal of time for plants to make a dent in the air, that's true. If you wanted it done within a few human lifetimes, then you'd need a more drastic way such as blocking all sunlight from reaching the surface to cool it down, then find some way to keep the carbon from re-vaporizing and starting the greenhouse process all over again.

Well, yeah, except I never said I wanted to terraform it, I wanted to find a USE for Venus, like mining the atmosphere.

Tourism? Seriously, just set up tourist tours to and from the planet. Just imagine the pitch: "Visit our sister planet. Bathe in the seas of liquid lead and observe the majesty of the sulfuric rain."

A civilization that has enough resources to do any meaningful space mining and engineering will have enough resources that they don't need to do anything else.

[Borgholio]

I never said it would be quick. It would take a great deal of time for plants to make a dent in the air, that's true. If you wanted it done within a few human lifetimes, then you'd need a more drastic way such as blocking all sunlight from reaching the surface to cool it down, then find some way to keep the carbon from re-vaporizing and starting the greenhouse process all over again.

Well, yeah, except I never said I wanted to terraform it, I wanted to find a USE for Venus, like mining the atmosphere.

Well in that case high-altitude farms would be a great breadbasket if Earth needed food. High CO2 content and abundant sunlight.

[Broomstick]

Hmmm... but would life adapted to the high sulfur, acidic environment actually be edible to typical Earth lifeforms like humans?

[Borgholio]

Well it wouldn't have to be open to the air. If a material that is sufficiently acid-resistant can be found, then fresh (acid-free) air can be filtered in to the plants to provide the air they need.

Come to think of it, even if such a material might be found, it'd probably be easier to just deploy orbital shades to cool the planet. There's nothing worth mining in the atmosphere and if they really need Venus to grow food, it'd be easier to just terraform and grow on the surface, and have access to all the minerals in the crust as well.

[Solauren]

#1 - Suck off as much of Venus's atmosphere as possible. Take that to greenhouses for plants to metabolize into oxygen and other more usable organic compounds. Store any excess atmosphere until needed. Is it feasible to freeze it into blocks and put it somewhere will it will not melt?
#2 - As Venus loses atmosphere, it's temperature and air pressure will drop. This means Venus will start giving off a lot of Infrared radiation. Solar panels that can capture that energy would be good.
#3 - Eventually, the planet's temperature will lower to the point where properly shielded machinery and buildings can be landed to begin mining, this would have the added benefit of reducing pressure on it's mantle and lowering seismic activity.

Actually, those uses for Venus could, eventually, start getting to the point where Teraforming is feasible and desirable.

[Darmalus]

Planetary Theme Park

Convert the atmosphere to oxygen/nitrogen, but keep the pressure. Have floating cities riding up where normal humans can breathe. Seed the world with lifeforms that swim in the high pressure air. Flying whales, floating forests, etc. People can telepresence down or wear a diving suit to visit the surface.

If we can visit Venus, there are much easier places to get resources other than at the bottom of a gravity well. So why not entertainment and exotic living locations instead of resource extraction?

[Enola Straight]

I was wondering about going the other way - shrouding venus with orbital mirrors. With less energy going in, the atmospheric heat will drop until a new equilibrium is struck.

let the C02 freeze out of the atmosphere, box it up (lol) and remove the mirrors. slowly add CO2 back as the plants grow. If a space elevator is possible, shipping co2 to mars sounds nice.

Some threads of mine over at the SDMB:

http://boards.straightdope.com/sdmb/sho ... p?t=722038

http://boards.straightdope.com/sdmb/sho ... mars+venus

Broomstick's SDMB thread:

http://boards.straightdope.com/sdmb/sho ... p?t=724937

[Guardsman Bass]

Getting rid of the atmosphere to create a near-totally dry Venus might be a good thing in terraforming terms. Some of the more recent modeling on Habitable Zones suggests that "desert planets" could remain at hospitable temperatures far closer to their stars than planets like Earth, because there's much less water to create a runaway greenhouse effect. So if you could somehow dry out Venus and give it an oxygen atmosphere and a biosphere capable of maintaining it (maybe one with only sub-surface water aside from the poles), then you might be able to turn it into something human-habitable.

[Broomstick]

I thought Venus didn't have much water, even in vapor form.

[Guardsman Bass]

It doesn't now, but earlier in its history . . .