This is a poll that discusses the old idea of altering the atmosphere of Venus. Carl Sagan proposed this in an article titled "The Planet Venus" in the 1961 edition of journal Science. Sagan suggested seeding the upper atmosphere of Venus with algae to remove CO2 (carbon dioxide) thereby reducing the greenhouse effect. His idea was based on the algae effect on the very early atmosphere of Earth, which was similar to Venus. On Earth, ancient algae plus water evaporation converted the mostly CO2 atmosphere into oxygen and hydrogen eventually allowing for more comfortable temperatures.

Given what we know of Venus today, is there any hypothetical way that Venus could be transformed into a tropic Tahiti Planet?

Request: If you're thinking "We've got enough problems here on Earth. What about global warming?" Good point, but please go to the threads that exist now because this is only about Venus, and is hypothetical and for fun. I request that Earth references be made only as they pertain to the idea of Venus atmospheric change.

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"Insignificant molehill sometimes more important than conspicuous mountain." - Charlie Chan

P.S. Any Venus transformation ideas outside the 5 poll questions are certainly welcome.

The Carl Sagan proposal won't work. Even if seeding worked, the carbon and oxygen would get back together. Ultimately, it would take very high technology and, by present standards, immense transfers of energy and materials, probably with permanent artificial structures to maintain Venus (sunshades and reflectors for a reasonable day/night cycle). It's physically possible, but it wouldn't be easy. There are also likely limits to how quickly it could be done even assuming very advanced technology and the easy transfer of great amounts of mass around the solar system.

If we want to try terraforming, I think Mars would be the first choice, but that would require high technology, and probably permanent artificial structures as well. The requirement for self replicating (and self repairing) machines is pretty much a given. Those replicators could be macro, micro, or nanoscale.

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The Leif Ericson Cruiser

Wouldn't it be much easier (tech wise) to terraform Mars, than to terraform Venus?

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"The facts gentlemen, and nothing but the facts, for careful eyes are narrowly watching." Isaac Asimov

I think it is a given that Mars should be tried first but does that mean you exclude Venus out of hand - why not try for three habitable planets within our star system. OK the Sagan idea would not work but there surely have to be to other ways of locking up the carbon and freeing up the Oxygen - mybe some selfreplicating nanotech solution would provide the basis for this - especially if those nanotech machines used the carbon to build themselves.

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Maybe. It would depend, I think, on the specific details of what you're trying to accomplish. "Earthlike" would, I think, be just a little bit easier on Venus, assuming you have the ability to modify what's already there. "Livable" would perhaps be easier on Mars.

The challenge on Mars is that you really don't have the basic building blocks in place in sufficient amounts to reach "Earthlike". No liquids (let alone water) that we know of. The atmosphere (such as it is) is carbon-based, but so thin you'd have to haul in what you needed (and eventually lose it all to outgassing anyway). Much less energy provided by the sun.

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And you, to whom adversity has dealt the final blow
With smiling [faces] lyin' to ye' everywhere ye' go
Turn to, and put out all your strength of arm and heart and brain
And like the Mary Ellen Carter, rise again.

http://www.redcolony.com/wiki/index....adian_Approach provides the details for terraforming Venus, Mars and the moon in the benefits section of the attachment. Once we get a few power beam generators, interstellar vehicles, and Earth orbit ferries in operation the plan will fall together. The key is robustness of the transportation system, a commensurate energy source, and successful genetic engineering, if needed, of appropriate microbes.

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For those inclined to oppose human meddling with the structure of the universe or the composition and configuration of objects and groups of objects within the universe, consider:
Whether there is a limit to the magnitude of a modulation of chaos below which order remains invariant? Or, is order but a fiction invented by perspectives applied over finite, however large, time intervals?

Probably, but not very easy even there.

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The Leif Ericson Cruiser

Just give me a nice little Bernal sphere to call home and I'd be happy. You can keep the planets as vacation destinations.

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"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
"The Mayan symbol for "book" looks a lot like a triple hamburger, but I've never seen them claiming it as proof the Mayans had Big Macs." - KaiYeves
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

Well, we have seen some evidence of liquids on Mars. More importantly, there's a good chance there is still quite a lot of frozen water under the surface. Of course, we need a lot more information on this. Assuming there is a lot of ice, it would take time (a long time) to unfreeze a significant amount of the permafrost. But, even given the uncertainties, Mars does far better than Venus in the water department.


Atmospheric loss takes a very long time on human timescales, so that wouldn't be a significant issue for us. Producing atmosphere would be a biggier issue, and it is unclear if there are sufficient materials to produce a good atmosphere on Mars (I suspect importing would be a requirement). Temperature is a major problem and would be a key reason there would probably need to be permanent artificial intervention. Of course, Venus has the opposite problem: Too much atmosphere (and it isn't easy to deal with) and too much sunlight. Then there is the slow rotation rate.

One other point: Since Mars is smaller, the scale of operations (solar reflectors, mass moved, and so forth) would be significantly smaller than for Venus. Still REALLY, REALLY BIG by present standards, but smaller.

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The Leif Ericson Cruiser

Venus terraforming was discussed here: How much quicklime would it take to terraform Venus?

My suggestion was vacuuming the excess atmo away. Another was converting it into diamonds full of oxygen.

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"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
"The Mayan symbol for "book" looks a lot like a triple hamburger, but I've never seen them claiming it as proof the Mayans had Big Macs." - KaiYeves
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

Now where did I put Megamaid?

__________________
And you, to whom adversity has dealt the final blow
With smiling [faces] lyin' to ye' everywhere ye' go
Turn to, and put out all your strength of arm and heart and brain
And like the Mary Ellen Carter, rise again.

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
"The Mayan symbol for "book" looks a lot like a triple hamburger, but I've never seen them claiming it as proof the Mayans had Big Macs." - KaiYeves
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

James Oberg discussed the idea of removing the atmosphere in New Earths. I don't have the book with me right at the moment, but I remember that the energy input would be enormous to do it in a reasonable time. Think solar collectors far wider than a planet. And the physical process of removing the atmosphere would be a bit of a trick too (just try to build a practical Megamaid!).

I know of two books that focus on terraforming. One is Oberg's New Earths, which is nice, but it doesn't go into much detail, and was published in '81.

Fogg's Terraforming is much more detailed, somewhat more recent, but is out of print and used copies are really expensive (Amazon has them starting at $750, and I've seen over a thousand - no I didn't pay anything like that when I bought it new). It's much better, but it still leaves out most of the math, and there is so much more that could be covered.

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The Leif Ericson Cruiser

Though Sagan's suggestion is not workable and of its time as we now know more about Venus, it has an appeal only by way of its elegance. Though such a scheme if workable would require a lot of machinery, the simpler appeal lies in the idea that we dump something that alters the CO2 in the atmosphere and the temperature drops, it rains a lot and we eventually walk around on the surface without burning up.

The idea of a nanoscale influence somehow simultaneously working on the lower atmospheric levels and surface to aid in lowering temperatures while radical changes take place in the upper atmosphere is intriguing. But, if it were workable in any way, I strongly suspect it would be a vast multilayered project pulling in a great many steps and interrelated technologies over a very long time.

I like the recipe analogy like baking a cake. The prep work assures success and then its all put in the oven and we return when its done. The structure, but not the specifics of the Sagan plan has that appeal, as if we do steps A, B, and C then watch from Earth as Venus changes from an totally inhospitable terrestrial planet to an inhospitable terrestrial planet we can land on, (like an earth sized Mars,) then gradually into a more hospitable planet we can eventually live on. But even if such a scheme was workable, its not that easy.

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"Insignificant molehill sometimes more important than conspicuous mountain." - Charlie Chan

Two questions;

1) What's his definition of a reasonable time frame?

2) Does that count energy already present on the planet, such as using the atmospheric pressure to drive the suction process?

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"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
"The Mayan symbol for "book" looks a lot like a triple hamburger, but I've never seen them claiming it as proof the Mayans had Big Macs." - KaiYeves
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

Before the sun's expansion renders the issue moot, hopefully.

__________________
And you, to whom adversity has dealt the final blow
With smiling [faces] lyin' to ye' everywhere ye' go
Turn to, and put out all your strength of arm and heart and brain
And like the Mary Ellen Carter, rise again.

I'll look it up later when I can get to the book. I think he was figuring centuries. As for the sun heating up - well, Venus would probably need a permanent sunshade anyway. Then again, while I could hope something that is in some way our descendant would exist that far in the future, I would be astonished if it was still anything like us.

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The Leif Ericson Cruiser

A simple solutuion for Terraforming Mars.

Lob jupiters moon Eruopa at it for a impact event, this will provide it with more water and mass, and would likely reactivate plate techtonics on mars. Next lob IO at mars, but into orbit, to become a stablising moon.

Wait a few hundred years for the surface to soldify again and wala, a half baked earth like world!

Easy as pie

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There is no problem that cannot be solved by a suitable application of high explosives - US Army Demolitions School

I just saw Hayley's comet, she waved, Said "why you always running in place? Even the man in the moon disappeared, Somewhere in the stratosphere" - Shinedown

http://worldsofothersuns.home.comcast.net/

Tossing moons around like that will probably require a lot more effort than terraforming!

How much water would be lost to space in a collision between Europa and Mars at orbital speeds? I'm betting it's a lot... And how long would it then take for Mars' surface to stabilize enough to introduce life and/or colonize? Probably more than a few hundred.

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
"The Mayan symbol for "book" looks a lot like a triple hamburger, but I've never seen them claiming it as proof the Mayans had Big Macs." - KaiYeves
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

All true.

I was intentionaly oversimpling it for a little humor.

Seriously of the two, Venus and Mars, I think mars would be the better choice. But with both having almost no magnetic field, (inactive cores?) neither one would be a long term solution due to the increase in radiation exposures without a shielding mag field.

__________________
There is no problem that cannot be solved by a suitable application of high explosives - US Army Demolitions School

I just saw Hayley's comet, she waved, Said "why you always running in place? Even the man in the moon disappeared, Somewhere in the stratosphere" - Shinedown

http://worldsofothersuns.home.comcast.net/

Looked at that way, Earth isn't a long term solution either. So we'd better try to live in as many places as we can, because no one solution is guaranteed to work forever.

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
"The Mayan symbol for "book" looks a lot like a triple hamburger, but I've never seen them claiming it as proof the Mayans had Big Macs." - KaiYeves
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

Okay, here's the relevant text (and I'm skipping some bits) from New Earths, page 212:

"If we wish to remove 98% of the mass of the Venusian atmosphere in a reasonable time, say, 100 years, we must haul up a mass 10 quintillion tons, or 300,000 tons per second. Compare that to the flow along the Amazon river . . . 10,000 tons per second. The largest machines built which handle flowing water . . . handle 400 tons per second.

Or look at it from an energy requirement: hauling the mass of gas 100 km high, and then accelerating it by 20 km per second requires about 10²⁵ ergs over a 100-year period. That's all the sunlight falling over the same period on an area of 10,000 square km assuming 100% efficiency . . .Throw in a factor of 10 for engineering reality, and the air scoopers must have an area of . . . three times the total area of Venus."

He suggests giant ramscoops connected by elevator/cable to hardware higher up. The ramscoop collects air, compresses or liquifies it, ships it by tanks up the elevator, where it is accelerated away from the planet. There are a number of design issues with these scoopers.

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The Leif Ericson Cruiser

Okay, so he's ignoring orbital suction tubes in favor of treating the atmosphere like freight. Not the most practical method. A tube leading from a lower altitude to the upper atmosphere or higher would work just like a drinking straw, although it would be harder to engineer than an orbital elevator. As for 100 years, I just can't see it happening that fast; more likely, Venus will become the CO2 distributer for the Inner Solar System, with a monopoly lasting centuries until the supply runs low. Then we start terraforming.

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
"The Mayan symbol for "book" looks a lot like a triple hamburger, but I've never seen them claiming it as proof the Mayans had Big Macs." - KaiYeves
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

I don't think we'd want to get rid of the venusian atmosphere out of hand, just because it's hot. There should be some method if carbon sequestration, but using life forms may not be easy with the slow rotation. Only half the planet would be useful for photosynthetic carbon sequestration. Perhaps there would need to be chemosynthetic life forms as well.

Structures could be useful. A sunshade of some sort is probably necessary. A reflector would also be useful. Perhaps high altitude balloons would be useful for creating hanging gardens that would serve as a biological reserve. But I think it would be more important to lower the temperature first.

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"What you think you thought you saw you did not see." Agent J, MiB - Manhatten Bureau

He dismisses suction on page 210:

The gases can not, of course, be sucked up the line since vacuum pressure is not nearly powerful enough to raise them hundreds of kilometers to the mother ship.

Remember, you have to move the gas up against the gravity well. Nor is just moving it up enough - you want to get it up to escape velocity to keep it from landing on Venus again.

That was just a convenient number for the calculation. The key point is that it would take some very impressive hardware and lots of energy - far, far more than we would need to solve world energy problems with ease.

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I say there is an invisible elf in my backyard. How do you prove that I am wrong?

Disclaimer: Avatar is not an official NASA image and does not imply any specific interplanetary or interstellar capability.

The Leif Ericson Cruiser

True. It would also require large numbers of people with the ability to stay in space long-term, likely for generations; and if we've already got that, who needs Venus?

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
"The Mayan symbol for "book" looks a lot like a triple hamburger, but I've never seen them claiming it as proof the Mayans had Big Macs." - KaiYeves
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

An atmosphere thick enough to breathe does a good job stopping radiation. Both Mars and Venus have a greater scale height than Earth (and that's especially true for Mars). Keep in mind that your radiation dose goes up if you move to Denver, but cancer rates aren't obviously higher there. Anyway, I would expect that if we had terraforming tech we could also deal with cancer.

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I say there is an invisible elf in my backyard. How do you prove that I am wrong?

Disclaimer: Avatar is not an official NASA image and does not imply any specific interplanetary or interstellar capability.

The Leif Ericson Cruiser

As I said, I prefer Mars over Venus as a terraforming target. However, the issue may not be so much about absolute need as what people of that time find desirable. If you have self replicating machines, and given enough sun for three billion Earths, it may not be that expensive to scale up industrial capacity to terraform Venus. Right now, all we can do is speculate.

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I say there is an invisible elf in my backyard. How do you prove that I am wrong?

Disclaimer: Avatar is not an official NASA image and does not imply any specific interplanetary or interstellar capability.

The Leif Ericson Cruiser

It's very hard to say what people of the future would want to do. If they have self replicating machines then a machine smaller than a pea could be used terraform an entire planet. The cost of making that probe could be less than a cent. It's hard to imagine what people with that sort of wealth would want, let alone do.