Terraforming Venus

[poi]

Is there any chance that a package of microbes could be introduced to Venus' atmosphere that would begin a process transforming it into something more conducive to a human presence?The process would certainly require many years but by the time we are able to visit Venus, the planet might be ready to recieve us.This could be considered contamination but is there any serious hope of finding life there?That seems to be the only reason not to try developing and sending a suitable microbe package.It seems too obvious an idea not to have been considered so can someone tell me how it can't be done or why it shouldn't be done?

 

[kelvinzero]

Hello Poi,

It is actually quite a famous idea, apparently brought up by Carl Sagan

That and some other approaches are mentioned here:
http://en.wikipedia.org/wiki/Terraforming_of_Venus

According to that link, a problem with a biological approach is that Venus has very little hydrogen.

My favorite approach is solar shades of some sort, probably manufactured on the moon.

 

[MeteorWayne]

This will be merged into the existing dicussion on this topic.

 

[poi]

Thanks for the infK , Sagan's approach couldn't work but couldn't the excess atmosphere be transformed into something else that would be blown away like hydrogen or fall to the surface.I like the bio approach because sending a small microbe package is something is something we could do in the near future.The other approaches sound like they could only be done 50 to 100 years in the future.

 

[kelvinzero]

These are only the guesses of someone with basic uni physics but

I would guess no element can get blown away as easily as hydrogen. Hydrogen is much lighter than any other element.

I don't have the knowledge to say there is nothing else life could do with the CO2, but if there were something applicable it would probably be well known even if it were very speculative; people have been exploring these sorts of ideas for some decades at least.

 

[poi]

Would hydrogen be the only option?If so is there no chance of making a microbe that could transform co2 into that?How about helium?Could that be blown away too?How heavy a gas can it be and still be blown away?

 

[kelvinzero]

Ah, I had forgotten helium. I think that is very abundant in the universe but very rare on earth.

My guess is that helium is even easier to get blown away because unlike hydrogen it does not tend to bond chemically to form heavier molecules.

Of course you cannot transform CO2 into hydrogen or helium, nor could any reaction involving CO2 on venus release hydrogen or helium elements in significant quantities if these elements do not exist on venus in significant quantities.

 

[poi]

How about transforming the Venus atmosphere into a non-greenhouse gas or into something that would fall to the surface?

 

[SteveCNC]

How about transforming the Venus atmosphere into a non-greenhouse gas or into something that would fall to the surface?

Well that's always been the basic premise of teraforming venus was to introduce a bacteria or series of them to alter the atmosphere by feeding off the bad gases and converting the carbon and sulfer to solids or by absorbing it and falling when the bacteria dies , which has potential but the scale would be rather extreme unless it was self replicating . And self replicating has it's own problems should we go down that road , not the least of which is we could potentially kill the planet with good intent or even our own . Then we would be looking for a way to kill the killer . That sort of thing has never really settled well with me , it's not all the horror movies I grew up watching that makes me that way or the fact that at one time in my life I was religious and still have sympathetic feelings towards it .

I just think there's too much potential for serious disaster and it dosen't justify the gain . Even if you got the atmosphere under control what are your plans for a magnetic field and some ozone . And after that your going to need to clean up a pretty thick carpet of dead bacteria from cleaning the atmosphere . not to be a downer but I don't really see venus as being worth the struggle . Starting up a magnetic field would be insane with todays technology , something on the order of an ant colony building one of the great pyramids . not likely .

 

[EarthlingX]

Here's another thread, which is dealing with Venus :

SDC : Catalytic Enzymes and cleaning up Venus' atmosphere?

Don't let the title fool you

 

[crazyeddie]

Venus has almost no detectable water. No organism that we know of can exist without using water as a solvent for it's metabolic processes. Until we have a way of delivering water to Venus in sufficient quantities for bioengineered organisms, the idea of terraforming Venus in this manner seems impossible, or at least, impractical.

It might be easier to build a solar shield, sometimes called a soletta, to cool the planet and freeze out it's CO2 atmosphere, which could then be removed or reworked into carbon and oxygen. But you still run into the problem of lack of hydrogen.

 

[neilsox]

How about transforming the Venus atmosphere into a non-greenhouse gas or into something that would fall to the surface?

That is one of many ideas that have been analyzed in several old threads. Most of the ideas are incredibly costly with technology likely soon, plus they create new problems and/or leave Venus still uninhabitable by humans.
Quick lime = calcium oxide (and/or several other metal oxides) absorb CO2 forming limestone = calcium carbonate which is a stable solid below about 500 c = 932 f, so that will work, except where do you get a mountain range of a suitable oxide and an average depth of 600 meters of limestone on the surface would not be very Earth like, plus Venus would still be too hot for humans, unless we also instal some giant sunshades = soletta.
The Fogg plan with just the right number of sunshades would give Venus large oceans of liquid carbon dioxide, a comfortable temperature, but higher sea level air pressure than present humans can tolerate (long term) but genetically altered humans might enjoy playing naked in the liquid carbon dioxide. Does anyone know what the new sea level pressure would be? Downside is the liquid CO2 would likely keep the humidity near zero, and would dissolve lots of other elements and compounds. Neil

 

[bearack]

Venus has almost no detectable water. No organism that we know of can exist without using water as a solvent for it's metabolic processes. Until we have a way of delivering water to Venus in sufficient quantities for bioengineered organisms, the idea of terraforming Venus in this manner seems impossible, or at least, impractical.

It might be easier to build a solar shield, sometimes called a soletta, to cool the planet and freeze out it's CO2 atmosphere, which could then be removed or reworked into carbon and oxygen. But you still run into the problem of lack of hydrogen.

I always thought Venus had a substantial amount of water vapor in the upper mesosphere, viewed over a period of 3 years or so??

A little research, I also found that the Venus Express also detected substantial amounts of vapor, but nearer the surface.

Water vapor abundance near the surface of Venus from Venus Express/VIRTIS observations

 

[Couerl]

I don't think water is the real problem.. It should be mentioned that Venus is somewhat like an Earth that never matured much past its own hadean, possibly because of low plate-tectonic activity (I.E. no moon or tidal forces in play). Earth itself has only .006% water content believe it or not despite the fact that 70% of the surface is water and it is likely similar to the moon and Venus and perhaps even mars as far as water content/composition goes since it's all made from the same stuff (although most of the water on mars was probably released and blown away when its core solidified and it lost its magnetic shielding etc..).

The idea of introducing organisms or using sun shades to convert anything even if they could survive or "freeze out" doesn't help us any time soon and that time is the real hindrance.. The time it took for Earth to rain out its S02 in the upper atmosphere was around 200 ml years during the hadean I believe and that is when the oceans formed. Venus still has that huge amount of So2 in its upper atmosphere and that is where we would need to start. I figure even with sun shades and whatever else it would take millions of years to "terraform" Venus and that is assuming everything we did went just right. So2 rains out, acid eats rock, rock releases water molecules, water sequesters Co2, atmospheric pressure lessens and ozone develops from lightning storms and bacteria can do the rest in around 2 bl years.. :lol:

 

[neilsox]

Another source inferred the water vapor comes from decomposition of sulphuric acid, which likely will not occur after terraforming. So water vapor is now about 44 parts per million, independent of latitude. Is that less than 1% relative humidity at 90 atmospheres of mostly CO2, 450 degrees c?
If we lose no water terraforming, does 44 PPM become more than 1% relative humidity at 10 atmospheres, mostly nitrogen, 2% oxygen, 31 degrees c, which I think is about the Fogg solution conditions? Neil

 

[EarthlingX]

This might fit here :

[youtube]http://www.youtube.com/watch?v=Ehgs3qazcvw[/youtube]

 

[ZenGalacticore]

While it would be great to terra-form Venus into a more Earth-like world, you guys are neglecting to mention the rotation period of the planet.

Venus' day is 243 Earth-days. And its year is 225 Earth-days!

Even with a more desirable atmosphere, that slow rotation, that much closer to the Sun, is going to cook you really good on the day side.

It would seem that we could speed up its rotation somehow or another though; and it would be surreal to say the least as the Sun rises in the west and sets in the east!

Oh yeah and, as Earthling X's great vid above mentions, like Mars, Venus has no magnetosphere to protect from coronal mass ejections and cosmic rays.

 

[Couerl]

Well assuming we could ever terraform Venus to begin with it seems a rather simple matter (proportionatly speaking) to create artificial day/night environments either on a small/local scale within structures etc or what have you.. Getting the planet to spin faster is unfathomably less practical than setting up a large dome with a light switch. :geek:

 

[ZenGalacticore]

Well assuming we could ever terraform Venus to begin with it seems a rather simple matter (proportionatly speaking) to create artificial day/night environments either on a small/local scale within structures etc or what have you.. Getting the planet to spin faster is unfathomably less practical than setting up a large dome with a light switch. :geek:

Well, as long as we're just having fun here. Theoretically, since Venus is 82% the mass of Earth, we could bombard it with watery comets at a certain angle of trajectory to not only speed up its rotation, but add to its paltry hydrosphere.

If we gave her 18% more mass in the form of water, who knows what would happen. Might help cool the old girl off a bit!

Seems like it's something we could seriously contemplate in the next 1,000 years or so...

 

[neilsox]

Hi Zen: Those seem like minor problems compared to doing something about the huge surplus of carbon dioxide = CO2. Do all the comets (including the Oort cloud) have enough water to equal 18% of the mass of Venus? My guess is an 18% mass increase impacted at an optimum angle would reduce the length of the day from 243 to 122 earth days = not much help. Worse optimum angle of impact is optimistic.
Likely the kinetic energy changed to heat would exceed the heat of vaporization of the comet ice by many times, so Venus would get hotter during the bombardment and at least briefly after the end of the bombardment. Since water vapor is a stronger greenhouse gas than carbon dioxide, hotter might last for 5 or 6 billion more years.
I think there are more Venus terraforming threads with other ideas, but none likely practical in this century, except a microbe injection might start a process that would remove a millionth part of the carbon dioxide per century = too slow to tell if the project was a success or failure. Failure is very probable unless we also use huge sunshades in the upper atmosphere or higher altitude. Neil

 

[ZenGalacticore]

Hi Zen: Those seem like minor problems compared to doing something about the huge surplus of carbon dioxide = CO2. Do all the comets ( including the Oort cloud) have enough water to equal 18% of the mass of Venus? My guess is an 18% mass increase impacted at an optimum angle would reduce the length of the day from 243 to 122 earth days = not much help. Worse optimum angle of impact is optimistic.
Likely the kinetic energy changed to heat would exceed the heat of vaporization of the comet ice by many times, so Venus would get hotter during the bombardment and at least briefly after the end of the bombardment. Since water vapor is a stronger greenhouse gas than carbon dioxide, hotter might last for 5 or 6 billion more years. Neil

Well sure, it'd get hotter in the "short term". But if we're talking about terra-forming a planet like Venus, we should expect it to take at least a few thousand years. And combine that 18% increased water mass with genetically engineered tough-ass CO2 eating, oxygen-producing microbes and bacteria, and who knows what we'd end up with?

Just let the two factors naturally take their course, and see what happens. After all, it can't get any worse on Venus. Perhaps engineer some microbes that would be happy digesting sulphuric acid as well.

And yes, I think the Kuiper Belt and certainly the Oort Cloud contain more than enough water to hydrate Venus. I mean, Sedna alone probably has enough water. And last I read, there are a few Sedna sized bodies out there. Not to mention the millions of other icy chunks orbiting in the far reaches of the Sun's influence.

 

[neilsox]

Yes that should work, except as I noted in the edit while you were posting, we likely also need huge sun shades as even calcium carbonate, decomposes into CO2 and quick lime at the present surface temperature of Venus. The incoming comets would punch holes in the huge sunshades, but perhaps that is only a moderate repair problem. The microbes need the water from the impacting comets to thrive, but they might barely survive with the present amount of water. Neil

 

[gravityTug]

Venus' day is 243 Earth-days. And its year is 225 Earth-days!

Yeah, that fact has always struck me with regards to Venus's plight. Does anyone have an idea as to how earth would be effected if it had a similar day/year cycle?

 

[crazyeddie]

Venus' day is 243 Earth-days. And its year is 225 Earth-days!

Yeah, that fact has always struck me with regards to Venus's plight. Does anyone have an idea as to how earth would be effected if it had a similar day/year cycle?

That's hard to answer. If you mean, "what would happen if the Earth's rotation was suddenly slowed to a rate comparable to that of Venus", then the answer would be, "a lot!". Currently, the Earth's relatively fast rotation pulls it into the shape of an oblate spheroid, and if it were to suddenly slow down, the dynamic pressures on the crust and mantle to assume a rounder shape would be huge. There would be earthquakes on a scale unimaginable. Once it settled down, however, it would not stay that way, because the moon's tidal pull would tend to speed the Earth's rotation up again. The weather would be drastically changed, since all of the solar insolation would be absorbed by the side of the planet facing the sun, which would get very hot. The atmosphere would try to redistribute the heat to the other side, which means the Earth would become a very windy place. Hurricane-force winds would probably be the norm over most of the planet, which, needless to say, would make life as we know it rather problematic.

On the other hand, if you mean, "how would Earth have been effected if it always rotated as slowly as Venus", then the answer would be different. Life may never have developed, because with such slow rotation the Earth probably would not have developed a protective magnetic field or plate tectonics, both of which are vital to our biosphere.

 

[ZenGalacticore]

Ed- And all those factors you mention lend serious credence to the "rare Earth" hypothesis.

It seems like so many things have to "go right" and "be right" for clement planets to evolve.

But, considering the number of stars and planets, it's bound to happen at least a million times out of 15 or 30 billion Sun-like star systems, seems like. But Earths could be comparatively rare jewels.