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I've wondered about the feasibility of transporting the abundant CO2 in the Venus atmosphere to Mars for the purposes of terraforming both planets at the same t
by Teever 6y ago
I've wondered about the feasibility of transporting the abundant CO2 in the Venus atmosphere to Mars for the purposes of terraforming both planets at the same time.
It's been a while since I've done the the envelope math but if I recall correctly there is more than sufficient CO2 on Venus to provide an atmosphere for Mars the issue is just transportation.
The last time I thought about it I considered some sort of massive floating solar powered comet builder that would cool the atmosphere into large chunks of dry ice that could then be wrapped in a metal sabot so that the comet could be accelerated to mars via a mass driver.
As with everything in space and terraforming the key is scale so the equipment used would need to built in situ out of carbon from the Venusian atmosphere.
We are of course still a ways away from mastering self replicating carbon based engineering but the idea of terraforming both planets at the same time is neat to me.
- baxtr 6y agoI love the thought. I also love the line of thinking here. I feel bad for having very different, mundane thoughts around getting rich with my next side project!
- raxxorrax 6y agoMars is probably not geologically active and has no protective magnetic field, so my first thought was to change that by hitting it up with a larger asteroid from the belt, preferably a metal rich one with significant mass. I first thought about its moons, but they are too small. I mean to achieve a complete planetary melting. That would be step one, step two would be waiting a few million years and see how it turns out.
- Teever 6y agoSuch a cataclysmic event isn't necessary. https://phys.org/news/2017-03-nasa-magnetic-shield-mars-atmosphere.html https://phys.org/news/2017-03-nasa-magnetic-shield-mars-atmo... The bigger issue with this idea would be getting enough hydrogen to Venus to create oceans. That would require hitting Venus with comets or possibly extracting hydrogen from a gas giant which seems impractical.
- beached_whale 6y agoThis is sounding a lot like the Golden Age series by John C Wright. By the time when the novel's take place, they have cleaned up the solar system of all dust and comets/meteors
- R0b0t1 6y agoIf you can extract materials from a gas giant it is probably best to just live around the gas giant. Short term Venus looks more amenable to life, though.
- bluGill 6y agoThat depends - where does energy come from. If we never figure out fusion, then it may be we can find the energy to extract a few materials, but not enough to live there long term. Depends on the material - a large platinum (very rare, the industrial need per year is greater than the total production in a century so industry makes do with something not as good) would be worth it, while iron is everywhere on earth so not worth it.
- HarryHirsch 6y agoWe already produce a significant quantity of ruthenium, rhodium and palladium in spent nuclear fuel and choose not to extract them. If these metals became more widely available the market price would collapse, which now would not justify both mining or nuclear reprocessing. Going to space to mine a nickel-iron asteroid would be out, for very much the same reason.
- dodobirdlord 6y agoGoing to space to mine a nickel-iron asteroid makes a lot of sense, because the material is then already in space and you can use it for orbital manufacturing without having to pay the energy cost of getting it out of Earth’s gravity well.
- bluGill 6y ago
- tkahnoski 6y agoI'd rather do that in a different solar system. Massive planetary collision like that is bound to have some unintended side effects.
- hervature 6y agoIf Hollywood taught me anything, it's that drilling into the stopped core and setting off nukes are the best way to get it started again.
- ClumsyPilot 6y agoNo,no! If you ram a giant asteroid into Mars, you will destroy all of it's crust, there will be no geology ir way to answer the question - was there ever life?
- s1artibartfast 6y agoThe magnetic field isn’t really a human scale problem. My understanding is that it takes on the order of a billion years for the solar wind to blow away anything but a hydrogen atmosphere.
- rbanffy 6y agoUv will break water and the solar winds will blow the hydrogen away. You'll need a lens to push the protons inwards so the don't blow the atmosphere away.
- s1artibartfast 6y agoWhat water? Atmospheric or ground,? it still seems this would be a multi million year concern.
- rbanffy 6y agoAtmospheric. We'd need a lot of water vapor in the atmosphere to power a greenhouse effect.
- m4rtink 6y agoWhat abput a world house instead ? https://www.orionsarm.com/eg-article/460e7e5f4977b https://www.orionsarm.com/eg-article/460e7e5f4977b You basically start by building a roof over part of the surface, then you pump it full of breathable atmosphere and inhabit it. Then another part and so on until you have covered the whole surface or got bored by it. A huge benefit if that you can get (localized) results almost immediately instead of pumping massive resource into regular terraformation for possibly hundreds of years to only have useful results at the very end. Also you can do this on worlds that would never hold an atmospere (Moon, asteroids) or would loose it over time (Mars).
- ChrisClark 6y agoThis is a common myth based on a misunderstanding of scale in the original facts. Yes, the atmosphere will blow away, but it takes millions of years. As humans, we only have to top it off every hundred thousand years or so.
- genmon 6y agoA space elevator that lifts chunks of atmosphere up till they freeze, and whips them towards Mars from the rotational velocity at the top?
- mabbo 6y agoI love this idea, but there is something missing: nitrogen. You need to extract some of that from Venus as well, and bring it with you. But if you really want to have fun with terraforming you should make Venus earth-like. I suggest an exciting starting point: build a solar shade at the Lagrange point and block the sun. That would eliminate most of the hard problems with Venus temporarily while we did whatever work is needed to get it spruced up. CO2 freezes to dry ice below -80C or so. You could let through just enough sunlight to get the atmosphere at a pressure humans can survive- then all we need is warm clothes and an oxygen tank. Once Venus is in that state, the problem is simpler- how to get all the carbon and oxygen separated so that the carbon stays in some kind of solid form. Oh, and we'll want to go get a load of hydrogen, likely from Jupiter, to mix with that Oxygen to form water. Your fleet of transports moving CO2 to Mars needs to make a detour on the way back. Edit: fixed a word and also lol, just start with building a planet-sized solar shade, says some a-hole on the internet.
- raducu 6y agoReactionless drives would be so nice. Not only could you transport materials around, but you could make Venus spin in 24 hours in ~10^4 years using currenr Earth electricity output and a super-conducting emDrive -- I did the math a couple years ago.
- aeternum 6y agoThere's really plenty of reaction mass around though. Could probably get it done quicker by having a few large drone ships that harvest reaction mass from the planet or nearby asteroids.
- m4rtink 6y agoReactionless drives are indeed nice and really really dangerous - they make Earth shattering relativistic projectiles a bit too much easy to pull off. Pair one such drive with a nuclear reactor and have it fly away from the sun for a while and then back - it will hit ludicrous speed on the way back, likely a good fraction of C. And there is hardly anything that can be done to prevent that as it needs just energy to gain speed, not bulky inefficient reaction mass.
- oconnor663 6y agoIf you could connect a long hose between the two planets, you could use it as a siphon :)
- Koshkin 6y agoI have a better idea: push Venus to an orbit between Earth and Mars and wait a little until Venus cools down a bit.
- GuB-42 6y agoDoesn't work ;) https://what-if.xkcd.com/143/ https://what-if.xkcd.com/143/
- oconnor663 6y agoOh shoot. What about a long and flexible Archimedes' screw?
- ivalm 6y agoI still feel the best bet for terraforming Mars is deorbiting ice asteroids. They are already available and already solid. Can provide co2 or water depending on asteroid type. Still need a source of N2.
- samatman 6y agoGeneral rule: don't lift anything out of an Earth-class gravity well that you can get from a shallower dimple in spacetime. Carbonaceous asteroids are pretty abundant, and Mars has oxygen in great quantity. The asteroid belt is also much closer to Mars than Venus is. Nitrogen seems to be the building block that's a bit scarce. Venus definitely has some, but it's unclear that it's the first or best source to tap.
- MayeulC 6y ago> Carbonaceous asteroids are pretty abundant Phobos should have plenty of carbon too, and it's not really far from it. IIRC, it's close enough that with our current tech, we could build a "space elevator" there, that drags in martian atmosphere.
- dodobirdlord 6y agoI’m sure the Martian crust has plenty of carbon to form an atmosphere. It’s a very common crustal element, and extracting it in situ is going to beat out any approach that involves transporting material through space.
- pault 6y agoThere was actually a recent video from PBS spacetime on YouTube that did back of the envelope math on just this subject. The result is that you would basically have to strip mine the top three meters of the entire surface to get enough carbon, and the energy required for the chemical reaction would be something like 100 years of today's global energy production.
- dodobirdlord 6y agoSounds substantially easier than any approach that involves moving a similar amount of mass up the Sun’s gravity well.
- 6y ago
- rbanffy 6y agoI think the first step is to cool Venus down. A giant parasol in heliosynchronous orbit (a bit inwards to compensate for the push light and solar winds give) seems to be the way to go. Mars could require less mass. I'd go for a charged ring structure diverting protons from solar winds and focusing them into a spot on the surface to replenish the planets lost hydrogen and directing electrons towards the the edges so that the atmosphere would slow them down. Imagine the autoras. After the sun sets, you'd see all those electrons plunging through the atmosphere and screaming in blue agony as they lose speed by hitting the CO2 molecules.
- chrisco255 6y agoMars' atmosphere is also 95% CO2. It's the pressure that makes the temperature so high in Venus, not CO2 concentration.
- SECProto 6y ago> It's the pressure that makes the temperature so high in Venus, not CO2 concentration No, it's the partial pressure of CO2.
- jameshadouken 6y agoIf anyone finds this stuff interesting I can’t recommend Issac Arthur’s channel on Youtube enough. Regular out-there content on Megastructures, terraforming and the fermi paradox always grounded in real physics.