Terraforming Venus - methods anyone?

DonPanic · 2004-02-15 15:55:26

Lo
There are rains on Venus indeed, but only in high altitudes,
never a drop on Venus land. Too hot

Maybe a better idea would be to pelt it with massive asteroids a la Armageddon.

Should be huge water ice comet so that water dissolves CO2

kippy · 2004-02-19 09:57:24

Hazer,

I never said that setting up the gauss rifle infrastructure would be easy. This is terraforming remember, nothing's easy. However, The Russians were able to land craft on the surface and they survived for a short time. That was in the 70's and I'm not even sure they were designed to last more than an hour anyway. I'm sure by the time anyone seriously starts considering terraforming Venus, the material science will have progressed to a point where digging robots could be sufficiently protected to last on the surface for a long time. Hell, with the creative use of Mylar, aerogel and some other modern materials, I'm betting we could have a craft operate on the surface today for a long time.

kippy · 2004-02-19 10:06:52

Should be huge water ice comet so that water dissolves CO2

You'd need quite a few of those. besides, you'd still need to actively do something to do all the dissolving. My idea is to being tanks of hydrogen from Jupiter and react it with the CO2 to make carbon and h2o via the Bosch reaction. I did a little math and it would take about 3.8x10^19 kg (a smallish asteroid?s mass) of hydrogen to convert the whole co2 atmosphere. The result would be a lot of graphite and about 10% of the water found on earth. A small fraction of that co2 could be processed to supply a few hundred milibars of O2 and the 3 mars of nitrogen could either be turned to soil or shipped off elsewhere like Mars. Shipping all that hydrogen would take a while but this is terraforming we're talking about

Shaun Barrett · 2004-02-19 20:35:21

What if the water remained in the atmosphere as steam? Water vapour is a very efficient greenhouse gas in its own right and may well keep Venus roasting at uncomfortable temperatures despite the huge reduction in CO2.
???

kippy · 2004-02-20 08:20:55

The water vapor would need to be condensed. At that point, you would need some kind of sun shade or dust in the atmosphere to block the incoming sunlight. Once you get that big rain though, the albedo of the planet is going to rise with a lot of surface water and possibly ice dependong on how cool you make it.

If anyone's interested, I wrote a long entry in my blog about terraforming venus. It does count on some abilities that we don't posess yet but doesn't all of this?

[http://redefine.dyndns.org/~zinthefe/bl … 00085.html]terraforming Venus

John Creighton · 2004-03-19 08:46:11

Doin’t terreform. Live in floating structures in the atmosphere and build diamond space stations (Oneal Colonies) out of the CO2 atmosphere. It is a fair ways off from our technology but so is Terreforming venous. When the CO2 is finally removed from the atmosphere much more then a new planet is gained from the experience.

SBird · 2004-03-19 13:37:41

Terraformin Venus would be a monumental task, even from the perspective of terraforming. The fastest way I can see of getting the Venutian atmosphere 'fixed' would be to start pelting Venus with BIG, say 200 mile diameter asteroids. The resulting impacts will blast much of the atmosphere into space. Of course, you'll probably get lots of volcanic activity from the holes in the crust that will release even more gas but eventually I suppose that you could get things under control.

However, as John just pointed out, it's probably a far better use of time to just build space colonies. You don't even need a planet for that - just put them in the asteroid belt where you've got lots of raw materials to work with and no big gravity wells to deal with.

kippy · 2004-03-23 15:19:54

I don't think impacts would blast atmosphere off. They might make things really windy but I'm not sure how a surface impact would cause the atmosphere to go anywhere.

That atmosphere has a lot of good stuff in it too. With some hydrogen from one of the gas giants, you could convert all the CO2 into water and elemental carbon. Don't forget those 3 bars of nitrogen. Those could be shipped off to Mars in trade or used locally for making soil.

SBird · 2004-03-24 16:27:46

OK, I ran numbers on Venus terraforming and they're good for some yuks!

1: removing most of the Venutian atmosphere.
Go to the Oort cloud and find about 16,000 100m diameter cometary nuclei or break up some large nuclei into small ones. Send them into the inner solar system on a retrograde orbit into Venus. As a result, about 4.2*10^17 kg of material hits Venus at 100 km/s. Since the fragments are small enough to burn up in the atmosphere, all of the kinetic energy is transferred to the atmosphere. The atmosphere is heated up to about 26,500 K. The temperature is sufficient that the mean molecular velocity is half the escape velocity so most of Venus' atmosphere is caught by the solar wind and carried off. Wait a hundred years for the surface too cool off and resolidfify and you're set! Also, much of the CO2 will want to reassociate as high molecular weight carbon material at the temperatures you're working with. There's a good chance that gigatons of carbon in the form of soot will come raining back down.

You had proposed moving something like 10^19 kg of hydrogen from Jupiter and running a Sabatier-like conversion of the CO2. That requires doing a chemical conversion of something like 5.2*10^20 kg of material as well as having to move 10^19 kg of gasseous materialinto storage and out of Jupiter's gravity well.

Moving the cometray nuclei would be difficult but realtively low energy as they sit on the edge of a long gravity well that will give then the impact energy for free. Plus they're self-contained so easier to deal with. I'd estimate that my scheme takes at least 3-4 orders of magnitude less energy to implement.

2: As for giving Venus an Earthlike-spin, that's easy as well!

Just hit it with one or two 100 km wide stone asteroids at 100km/s at a glancing angle and you provide enough kinetic energy to give Venus an Earthlike spin! Of course, the average planetary temperature goes up by ~120K and you've probably completely shattered the crust but it's Venus - it's not like anyone's going to complain! Just wait a million years or so for things to settle down and you've got a nice new planet.

I think that this sort of example shows just how absurd Venutian terraforming would get. I wouldn't rule out the possibility in the future, we're probably better off just letting Venus be and adapting our tech and ourselves to it instead. (the floating colonies mining the atmosphere are a fanciful but cool idea.)

PS: I particularly liked the bit on your webpage about the lead frost in the Venutian polar regions being like 'frost in a Christmas card from Hell'.

MarsDog · 2004-03-25 03:57:40

Would reflective baloons in the upper atmosphere work ?
For Earth, someone calculated the cooling effect of painting all roofs white.

Proposed not long ago; moving Earth's orbit away from the Sun with an asteroid shuttling to Jupiter and back, transferring momentum. Maybe we could replace the moon with Venus, but then where to put the Moon ?

SBird · 2004-03-25 12:37:11

Oi, I don't even want to think of the effects of the tidal forces on the Earth if Venus were in close orbit with us. Keep in mind that the oceans of Europa are liquid and Io is basically one big volcano of molten rock because of the tidal forces that come from Jupiter.

I suppose that reflective balloons around Venus would help but it would take a looooooong time to bring the temperature down. The Venutian atmosphere is basicallt a big blanket that holds onto IR radiation like its going out of style. The only way to really get it to become stably cool would be for plate tectonics and large quantities of water to be reintroduced.

kippy · 2004-03-26 14:40:55

I've still got my money on using hydrogen to process the CO2 into water. I'm all about making use of the local resources, not blasting them into space. We'll settle the bet in a thousand years.

Anyway, I had a thought about the sun shade. I can't see how big Mylar sails are every going to be workable even if we nail down 0-g manufacture and processing asteroids. Between them getting hit by micro-meteors and keeping them in place without crumpling up, they seem like nothing but trouble.

I mentioned using a big electromagnet or constellation of magnets at the L2 point to act as a shield for the incoming solar wind. You could probably also disperse some charges particles in there and the field would hold them in place. Deployment of the dust would be far easier than a Mylar sheet. For a sun shield, it could just be graphite dust gotten locally. For reflectors for Mars or somewhere needing a soletta, light dust or maybe aluminum could be used. You don't get the complete surface area coverage that a Mylar sheet would give but it wouldn't take an act of God to deploy it. This even sounds like something NASA could make a prototype of and test with today's tech. Hell, we could probably send one over and start the terraforming process now while we spend the next 100 years getting off of Earth. Not a bad head start.

Any thoughts?

kippy · 2004-03-26 14:56:50

You had proposed moving something like 10^19 kg of hydrogen from Jupiter and running a Sabatier-like conversion of the CO2. That requires doing a chemical conversion of something like 5.2*10^20 kg of material as well as having to move 10^19 kg of gaseous material into storage and out of Jupiter's gravity well.

It does sound crazy but remember the topic. Anyway, I wasn't suggesting that you get all that hydrogen in one trip. Rather you'd do it in hundreds (probably thousands) of trips. If you sent a tanker ship to skim the outer Jovian atmosphere, you could just open the front hatch and the pressure created by the speed of entry would probably fill it and pressurize it pretty well. After doing its aerobreak/fillup, you could probably work it so that it had enough energy to get back to Venus with a couple gravity assists from the moons and inner planets. I don't think there would be that big of an energy requirement if the ships are built "upgravity" near Jupiter and you make intelligent uses of gravity assists.

Reacting all the imported and native gas might not even require and infrastructure. Since the reaction happens spontaneously at Venusian temperatures, the tanker ships might be able to just open the hatch as they aerobreak at venus and the gasses would process themselves. It would just be harder to capture the carbon.

Anyway, no one said this would be quick but I don't think it would take a million years.

SBird · 2004-03-28 12:38:20

Ummmm, you do realize that Jupiter's escape velocity is about 60 km/s right? That's a biiig gravity well to climb out of. To be able to slingshot Jupiter, the probe velocity in Jupiter's upper atmosphere is going to have to be something like 65-70 km/s. I've got serious doubts that any real material can withstand any sort of prolonged contact with gass at those velocities. In order to collect any significant amount of material, you've got to skim at least deep enough to start hitting the low end of the molecular flow regime of pressure. I don't know how to calculate the aerodynamic heating and ion erosion of materials at those speeds but it's going to be ugly.

OTOH, once you get enough H2 into the atmosphere, random lightning shold cause the reaction 2H2+CO2->2H2O+C to proceed spontaneously via combustion. OTOH, I'm not sure how well the reaction will proceed at Venutian temperatures and pressures. Regardless, the remaining problem is that you now havea runaway greenhouse system with H2O rather than CO2 as the primary heat retainer. How exactly do we plan to deal with the 100+ atmospheres of H2O vapor? Not to mention the fact that the planet's albedo is approximately 0 because of all the precipitated carbon.

kippy · 2004-03-29 08:27:00

well if fusion is ever adopted the gas giants will be the big storehouses. If they can get to the He3, they should be able to get the hydrogen too. Maybe not though.

If the hydrogen is added to the atmosphere and you get 90 bar of water, all you need to do to cool it is put up a sun shade. pretty much every description of Venus terraforming includes one at some point. once you get a big water rain, the albedo will go way up if you end up with some oceans.

chat · 2004-03-29 10:48:04

I think Venus is by far the easiest planet to teraform.
What about this idea.

You go to the asteroid belt, pick the largest snowball you can find maybe 1000km if you can find it.
You return this asteroid that is 50% or more frozen water back to Venus.
But when you arrive back at Venus you don't collide the asteroid into Venus in a direct collision, you plan for it to do what scientist believe happened on earth to make the moon.

You collide the asteroid on a very angled trajectory.
The atmosphere on Venus is partially torn away, giant explosions in the atmosphere raise enormous amounts of dust into the upper atmosphere.
A good percentage of the h20 and hydrogen from the asteroid is em parted to Venus on the collision, and will be finding it way to Venus for years due to the mess that will be orbiting Venus after the Angled collision.
The remaining debris from the collision becomes a halo around Venus that blocks large quantities of sunlight for years.

Also if you plan the angled collision well, the collision can
a. speed up the planets spin.
b. create a small moon for Venus that stabilizes the planet.
c. make a nuclear winter that lasts for decades, and creates no nuclear contaminates.

A few weeks after the collision you release super carbon fixing bacteria to lock up the co2.

Any thoughts on this idea?

MarsDog · 2004-03-29 11:38:50

The orbit of the debris should be near the equator and could form a Moon for Venus.
-
If Venus rotated very fast, then part of the atmosphere could go into geosynchronous orbit, blocking the Sun.

SBird · 2004-03-29 12:23:30

Mars is by far the easiest of the planets to terraform. Venus is probably the second most easy. However, it's probably 20 times harder.

Sun shades are something that an engineer can doodle on a piece of paper but just can't be practically built. A reflective shade to raise the temp of aMartian polar cap is one thing. A shade that's blocking a significant portion of the total solar energy hitting a planet is another entirely. See the Mercurt terraforming thread for how crazy solar shades end up getting. I suppose that a Venutian shade is less crazy than the Mercury one but it's still very impractical. For one thing, you're talking about a structure that's a significant fraction of the diameter of a planet, massing billions to trillions of tons. If anyone has any suggestions as to how to build one of these, I'm all ears. Furthermore, if anything fails, your ecosystem rapidly fries.

kippy - The He3 mining schemes I'v seen involve big balloons floating in the upper atmosphere of Jupiter. The problem is that if you stop there, climbing out of the gravity well is VERY difficult. I suppose if you use that He3 to power some sort of futuristic fusion drive, it's not to bad, but the amount of energy spent is gigantic.

chat - go back up and you'll see my musings on hitting Venus with large numbers of small ice chunks. For one thing, there aren't any ice asteroids in the asteroid belt, you have to go out to at least the Kupier belt by Pluto or further to find any. Also, unless you deliver all of the kinetic energy to the atmosphere alone, not much gets knocked off. Even a huge impact would leave the atmosphere relatively intact. Also, your 1000 km impactor would shatter the crust of Venus. It's nota matter of waiting a few centuries for the 'nuclear winter' to abate - it's a matter of millions of years waiting for the crust to reform from magma. If you calculate the sorts of energy required to give aplanet spin and to loft a moon, the energy levels are just ridiculous. We're talking about events that raise the average temperatuer of the planet by hundreds of degrees C. Also, the formation of that moon would take eons and in the meantime would result in large amounts of meteoric material raining down on MArs for extended periods of time - read millenia.

Mars Dog - If Venus rotated fast enough to send the atmosphere into geosynchronous orbit, the entire planet would blow up like a skeet shot by a shotgun. You're talking about rotating the planet fast enough to largely negate gravity.

kippy · 2004-03-29 14:43:10

Sun shades are something that an engineer can doodle on a piece of paper but just can't be practically built. A reflective shade to raise the temp of a Martian polar cap is one thing. A shade that's blocking a significant portion of the total solar energy hitting a planet is another entirely. See the Mercurt terraforming thread for how crazy solar shades end up getting. I suppose that a Venutian shade is less crazy than the Mercury one but it's still very impractical. For one thing, you're talking about a structure that's a significant fraction of the diameter of a planet, massing billions to trillions of tons. If anyone has any suggestions as to how to build one of these, I'm all ears. Furthermore, if anything fails, your ecosystem rapidly fries.

Big shades are going to be a pain in the ass but not a showstopper in my opinion. Big sheets of tinfoil or mylar probably won't work because of deployment, tearing, etc. Consider though an electromagnet. It could be solar powered and made to cover a large area. The magnetic field would be able to hold charged particles so all you have to do is sprinkle charged dust into it and you've got a shade.

Getting field as big as the planet would be daunting but you could use several tethered together and put into a spin to keep them in place. It wouldn't be full coverage but you'd be able to block a good deal of the solar wind and sunlight. Best of all, you can add more dust easier than erecting a new sheet or mylar. likewise, you can gather it up if you want to let more light through.

kippy · 2004-03-29 14:57:59

kippy - The He3 mining schemes I'v seen involve big balloons floating in the upper atmosphere of Jupiter. The problem is that if you stop there, climbing out of the gravity well is VERY difficult. I suppose if you use that He3 to power some sort of futuristic fusion drive, it's not to bad, but the amount of energy spent is gigantic.

Jupiter is probably a bad choice then but Uranus "only" has an escape velocity of 21 km/sec. 2/5ths of Jupiter and only twice as bad as Earth. It would take longer to get there but it would be easier to get it out. It’s also a lot colder so you would heat up less as you zoomed through the atmosphere.

You can tell I'm not giving up this idea without a fight

SBird · 2004-03-29 15:11:52

What you're basically talking about is an M2P2 type solar shade. There's some advantages and disadcantages to this approach.

advantages: much cheaper to make and easier to maintain. If one unit goes down, you can just fire up a quick replacement backup.

disadvantages: solar sail effect - if you are making the dust particles absorbtive/reflective, you are still getting giganewtons of thrust. With such a low - almost 0 - sail mass, it's going to be impossible to keep your sails in place. There's a reason that M2P2 is a hot topic in spaceship drives right now. i did rough calculations that showed that if you fired up a 100 kg craft in Mercury orbit with a ~90 km diameter M2P2 sail and a reflectivity of 1%, the spacecract would hit something like 0.1% of the speed of light in about 5 days as it blasted out of the solar system.
Problem 2: keeping the dust particles in the sail field. The sail field has a very weak effect upon the dust particles and at 15kW/m^2, it's going to require a VERY powerful field to keep your dust particles from just flying away.
Problem 3: most dusty M2P2 models figure on a 1% albedo, TOPS. Even that's not terribly plausible, a 1% reflectivity is pushing the limits.

Since we've got to bring the light level down to about 10% of the initial amount, you'd need 229 seperate layers of dusty plasma shields to get the light level down that far. Also, you're then throwing away Mercury's most valuable resource - solar power. There's no good way to harvest power from a dusty plasma sail that anyone's figured out yet.

The only way to attenuate the light with light materials would be a non-dusty M2P2 sail that stops the solar wind, catching a few hundred meganewtons of force and then a series of thin film solar collectors that progressively attenuate the light an collect power. Still, the engineering and maintainance of such a structure would far, far exceed the gross world product of the Earth today.

There's no good reason to try and terraform something like Mercury, just go below the surface and weather out the temperatures there. What you want to do is like paving the entire surface of the Earth (a much easier task, BTW) so that standard cars can go everywhere instead of making off-road vehicles and planes.

chat · 2004-03-29 16:53:58

SBird,

I guess it all depends on the velocity of the collision and the impactors size.

Your correct about the k belt for the location of the dirty snowball.
But i bet a few large 100km dirty snowballs are also in the asteroid belt to be used, and altering inner solar system comets trajectory is the easiest way to get an impactor to Venus.
Why go for pickup when they deliver

As you pointed out the colision of a 1000km asteroid on Venus would be a long tern planet wide disaster.
I was more putting out the idea that colliding things directly into Venus might not be needed.
And opening the idea that a near colision at Venus might be a way to strip part of it's atmosphere away.

And moving even a 100 km asteroid would be a gigantic task.
But we are tera forming

I doubt if its a good idea to move objects of 1000km around that have gravitational influence in the inner solar system anyway.
Sounds like a dangerous game of pool to me
Even a 10km object would take about 100 commities to discuss if thats ok.

The biggest problem on Venus is the heat and lack of a way for the planet to cool itself.

Blocking the sunlight is most of what is needed for any work to start to thin and clean the atmosphere.

The best solution i think is not one 100km asteroid but two of them, don't collide them into Venus, but into each other in orbit above Venus.
Keep the collision down to low velocities, and it keeps all the material in orbit above Venus.
And eventually what is left will make a moon.

This will make for eons of semi darkness on Venus, and little crust activity on Venus, and no planet destroying impacts.

Sure some meteorites will fall on Venus, but with the atmosphere it has, most won't even arrive to the surface.
They will simply blow up in the atmosphere causing more cooling of the planet and adding water and dust to the planet.

And you will still get a nuclear winter in a more subtle way with the occasional small collision on Venus.

Use smaller low angle trajectory impacts as you suggest to speed up the planets spin, and add hydrogen, h20 and more cooling atmospheric dust.

Once the place starts to cool down maybe 1 to 5 years, then genetic altered bacteria over 50 or 100 years should be able to lock away most of the free co2.
Also bacteria that leave behind lots of white stuff before they die would help alot on Venus.

If the sunlight starts to get to strong at any point, then another small collision on Venus's new moon will slow that down until a new planet balance is pretty stable.
Or a few small collisions on venus will also cool things down again.

Getting 80% to 95% of Venus atmosphere locked away wont be simple, and adding water will take a gargantuan effort.
But then quite a few plants and creatures other than people can survive at 10 or 15 or more times the surface pressure on earth.
Us humans may have to wait 50,000 years before we could tolerate the place.
But i bet bacteria and the small beasties will be quite happy there till we arrive.

I got this moon idea for Venus from wondering how devastating a collision on our moon of a 100km or smaller asteroid might be for earth for a very long time period.

chat · 2004-03-29 17:33:36

P.S

Yeah Mars is easier to do.
But easy is for wimps *lol*

Drop phobos and demos out of orbit.
That should stir things up.

RobertDyck · 2004-03-30 07:41:20

I have also thought that Venus was a prime candidate for terraforming. It certainly has sufficient gravity to hold an atmosphere, today it has too much. It has a greater mass of nitrogen in the air than Earth, plentiful oxygen bound in CO2, and planet engulfing water clouds. Surface area is 90.0% that of Earth, and 90% Earth's gravity. However, it turns out that those clouds contain all the water of the planet, and if all that water rained out it would still be a dessert.

Carl Segan's idea of biological terraforming is perfect for Venus. The ingredients to support life are there in the clouds, and micro-organisms with sufficient food and no predators will multiply exponentially. A genetically engineered bacterium could convert CO2 into an inert material that would precipitate out and collect on the surface. The details are a lot more complicated than Carl envisioned in 1961, but the idea is sound. This could reduce the pressure and eliminate CO2 as a greenhouse gas.

In the grand scheme, I would suggest leaving Venus' rotational period as is. After all, a planet is big; changing its rotation period is just not practical. Control its temperature by first reducing greenhouse gasses, then create an upper cloud layer to reflect sunlight. Studies have show that clouds on Earth have complex behaviour: they both reflect sunlight away and trap radiant heat in. Whether they are a net gain or loss of heat depends on their altitude. Control cloud altitude on Venus to create a net loss. Also add upper atmosphere gasses that are transparent to visible and long wave IR while reflective to UV and short wave IR. Radiant heat from the surface is long wave (the surface is warm) while IR from the sun is short wave (its surface is thousands of degrees hot). This is called spectrally selective and it's quite effective at controlling heat.

So terraforming Venus could start today by seeding its clouds with anaerobic, nitrogen fixing, photosynthetic bacteria. They would require the ability to form flaps from cell walls that could be flapped like wings to control movement in the air. I read that some aerial bacteria do this on Earth. They would also need a taxis to seek moderate air temperatures and water droplets. Seeking by temperature and water should keep most of then in air currents that keep them in the clouds.

Bill White · 2004-03-30 07:48:55

If we start with what RobertDyck wrote, and kept seeding Venus on a regular basis, evolution might well produce new variants of bacteria, fairly quickly. He is exactly right, tailor the bacteria to this energy rich, nutrient rich environment and they will grow and spread like wildfire.

Which is exactly why I believe any micro-organisms on Mars (admittedly more likely if there is methane) are the mere remnants of a past Gaia-state. There is no evidence of life spread like wildfire on Mars.

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Re: Terraforming Venus - methods anyone?

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