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Mars and Venus have interesting attributes, both have pluses and minuses.
Mars lacks nitrogen, Venus has more than enough
Venus lacks water, Mars has more
Mars does not recycle its crust, Venus has an active geology with volcanism
Mars has a near 24-hour day, Venus has a slow retrograde rotation
Mars has strengths, Venus has strengths.
If there was a contest, which planet can we terraform first, which one would cross the finish line first?
Where should we place the finish line? I think ultimately Venus can get more Earthlike than Mars, because it has a greater mass, and a more Earthlike gravity. Mars can maybe be made habitable sooner than Venus, depending on which standard of habitability we hold. Both projects will take longer than a single human generation to complete, barring miracles such as nanotechnology.
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Well, that all depends on what you're required threshold is to be considered terraformed. Breathable atmosphere? A self sustaining ecosphere - does it have to be terrestrial, or would an aquatic one count? Pressures and temperatures enough for a human to walk around with warm clothing and an oxygen mask? Does paraterraforming count? Planetary habitability lies on a spectrum.
I think Mars could be brought fairly rapidly to the point of having a flourishing aquatic ecosystem and some land plants, and be suitable for paraterraforming large areas. Getting it to a fully habitable state will take a lot more effort, and will probably involve either massive movement of volatiles across the solar system or big space lenses to bake them out of the surface. The latter may not make any economic sense to do, because most of the benefits from terraforming (radiation and meteorite protection, and a self sustaining ecosystem that can provide a surplus to sustain humans without relying on a fragile technological infrastructure) would already be there. If you can grow crops outside, or at least in unpressurised polytunnels, and there's enough oxygen in the air to make extraction the most economical means to gain it, and you can walk around and work outside without needing a vacuum suit, and you can even go fishing in the crater lakes...
As for Venus, it's a hard one. There's a lot we don't know about how it got to that state. Certainly, the biggest thing that needs to happen is to cool the planet. This should cause the atmosphere to collapse to a much lower pressure covering a liquid CO2 ocean. I think the ideal thing would be to chemically react the excess atmosphere with the rocks, which may require importing a lot of water to form carbonic acid - we definitely need water to get some oceans going. That will take a long, long time though. On the other hand, if we imported water first, we could perhaps get Venus to a point where the cloud tops are much more hospitable, and have floating islands with vegetation growing on the outside. If we could then shield the planet with aerostats, and get it to the point of having a ~7 bar atmosphere over a CO2/Water ocean...
Use what is abundant and build to last
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I was thinking maybe thickening the clouds would do the trick. If less light reaches the surface of the planet, then less will be absorbed and reradiated as heat, and less heat will be trapped by the atmosphere. So thickening the clouds reflects more back into space, and as the planet cools, some of the clouds precipitate out and produce holes in the cloud deck, so we have to patch those holes. So my idea is to have evenly spaced towers that create more clouds where they are needed to fill in those holes in the cloud layer. We will need more water, and to keep injecting it into the atmosphere until the saturation point is reached and clouds form. And we just keep on doing this, so the planet stays covered with clouds even as he temperature drops down below.
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Feeling bored Tom?
I think Terraformer has already said it all. Humans could live on Mars without substantial modification to the environment. Any changes we do introduce would make life easier, though it is unlikely we would ever reach Earth analogue conditions.
Venus on the other hand would require a lot of planetary engineering before anyone could set foot on its surface. Even after temperatures and pressures have declined, the prospects don’t look good. The planet is drier than the moon and has substantial gravity which complicates imports and exports. The weaker Martian gravity works in its favour for most human activities. If you ever want to leave or export something valuable, it is relatively easy. There are business models that work for Mars, it is difficult to see Venus as anything other than a prison. Mercury is a more promising prospect than Venus. There are literally hundreds of worlds in our solar system that would appear to be more attractive prospects.
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Feeling bored Tom?
I think Terraformer has already said it all. Humans could live on Mars without substantial modification to the environment. Any changes we do introduce would make life easier, though it is unlikely we would ever reach Earth analogue conditions.
Venus on the other hand would require a lot of planetary engineering before anyone could set foot on its surface. Even after temperatures and pressures have declined, the prospects don’t look good. The planet is drier than the moon and has substantial gravity which complicates imports and exports. The weaker Martian gravity works in its favour for most human activities. If you ever want to leave or export something valuable, it is relatively easy. There are business models that work for Mars, it is difficult to see Venus as anything other than a prison. Mercury is a more promising prospect than Venus. There are literally hundreds of worlds in our solar system that would appear to be more attractive prospects.
But the gravity makes it more earthlike, all other factors can be adjusted including the amount of light it receives, but gravity can't be changed. You can make Mars as Earthlike as its gravity will allow, but even if you adjust all other conditions, just taking a few steps will tell you that you are not on Earth!
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Antius wrote:Feeling bored Tom?
I think Terraformer has already said it all. Humans could live on Mars without substantial modification to the environment. Any changes we do introduce would make life easier, though it is unlikely we would ever reach Earth analogue conditions.
Venus on the other hand would require a lot of planetary engineering before anyone could set foot on its surface. Even after temperatures and pressures have declined, the prospects don’t look good. The planet is drier than the moon and has substantial gravity which complicates imports and exports. The weaker Martian gravity works in its favour for most human activities. If you ever want to leave or export something valuable, it is relatively easy. There are business models that work for Mars, it is difficult to see Venus as anything other than a prison. Mercury is a more promising prospect than Venus. There are literally hundreds of worlds in our solar system that would appear to be more attractive prospects.
But the gravity makes it more earthlike, all other factors can be adjusted including the amount of light it receives, but gravity can't be changed. You can make Mars as Earthlike as its gravity will allow, but even if you adjust all other conditions, just taking a few steps will tell you that you are not on Earth!
So what? Your question was which of the two will win the terraforming race. If you are asking which of the two will become indistinguishable from Earth most rapidly, the answer is neither. Neither of them will ever be anything like Earth. And it matters not at all. Mars could be a home to us right now and could have a living ecosystem (of sorts) within a century. It is plain to even the meanest intelligence that Venus can do neither. So your question has been answered.
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Venus gets closest however, a terraformed Venus will have 91% Earth gravity, a 24-hour day, 365 day year with seasons (with artificial lighting), it has active geology, a full nitrogen atmosphere. Mars may have to import nitrogen or have a thin atmosphere with a higher percentage of oxygen. It all depends on what your willing to do with it. Brute force techniques include changing its orbit, spin, and axial tilt, for a price, you can have another Earth in this Solar System. One can instead cloak Venus from the Sun, and introduce artificial lighting to produce those day and seasonal effects as well as generate an artificial magnetic field if desired. Venus needs to import a lot of hydrogen to make oceans with its oxygen. Mars needs to import a lot of nitrogen to bulk up its atmosphere, now which weighs more? the hydrogen to make the Venusian oceans or the Nitrogen to bulk up the Martian atmosphere?
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The hydrogen, by far. The Earth's oceans are kilometres deep. The atmospheric mass is about 2 orders of magnitude less, though still enormous.
You come up with some interesting ideas, but you appear to lack engineering judgement. You find it difficult to judge the scale of what you discuss and guage its practicality. Yet you seem capable of doing the math. Everything we discuss here is far out, mind you.
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Despite my username, I don't think humans in the plausible mid future will do any deliberate terraforming, if we take terraforming to mean the provision of a breathable atmosphere. The timescales are too long and the return for humans isn't that great, particularly if it requires maintaining a large, possibly space based infrastructure such as solettas - if you're going to rely on a technological infrastructure for survival, it's far better to have it be simple oxygen concentrators and lighting systems that are close enough for easy repair.
However, I do think well do a lot of proteroforming (habitable temperatures and pressures - think clothing and oxygen masks), ecopoesis, and paraterraforming. These things will take a lot less time and resources to accomplish, whilst offering us benefits in terms of protection (radiation and meteorites) and resources (ecosystem services, biomass, atmospheric buffering). After a few thousand years, perhaps we'll end up inadvertently terraforming planets, as their ecosystems transform their atmospheres.
Given that, I'd like to see Venus gain a lot more water, diluting the sulfuric acid in the clouds and allowing for the possibility of growing plants on the outside of balloons. This would probably raise the temperature even further, but that might not be such a bad thing if the colonists are extracting power by mining the atmosphere for heat. If the planet is cooled later, and we get a 7 bar CO2/Nitrogen atmosphere overlying a CO2/Water ocean? Still not terraformed, but it would be much easier to access the surface, and perhaps oxygen would be concentrated enough to be economically extracted.
Use what is abundant and build to last
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Despite my username, I don't think humans in the plausible mid future will do any deliberate terraforming, if we take terraforming to mean the provision of a breathable atmosphere. The timescales are too long and the return for humans isn't that great, particularly if it requires maintaining a large, possibly space based infrastructure such as solettas - if you're going to rely on a technological infrastructure for survival, it's far better to have it be simple oxygen concentrators and lighting systems that are close enough for easy repair.
However, I do think well do a lot of proteroforming (habitable temperatures and pressures - think clothing and oxygen masks), ecopoesis, and paraterraforming. These things will take a lot less time and resources to accomplish, whilst offering us benefits in terms of protection (radiation and meteorites) and resources (ecosystem services, biomass, atmospheric buffering). After a few thousand years, perhaps we'll end up inadvertently terraforming planets, as their ecosystems transform their atmospheres.
Given that, I'd like to see Venus gain a lot more water, diluting the sulfuric acid in the clouds and allowing for the possibility of growing plants on the outside of balloons. This would probably raise the temperature even further, but that might not be such a bad thing if the colonists are extracting power by mining the atmosphere for heat. If the planet is cooled later, and we get a 7 bar CO2/Nitrogen atmosphere overlying a CO2/Water ocean? Still not terraformed, but it would be much easier to access the surface, and perhaps oxygen would be concentrated enough to be economically extracted.
I am inclined to agree. Paraterraforming is something that will happen anyway if we live on Mars in large numbers. Everything that humans do on Mars will tend to drive up global temperatures. Greenhouses, radiators and solar power plants will have higher albedo than the planet's average. Big power plants may be located at poles, where they will dump waste heat by subliming CO2. Methane mining will lead to a portion of fossil methane escaping into the atmosphere. Ultimately, it will be difficult to avoid atmospheric thickening. I believe that active terraforming using super-greenhouse gases may be attempted, because the civil engineering advantages of a high atmospheric pressure are large, and this can be accomplished more quickly at a lower total cost than atmospheric processing. The quantities of gas required are hundreds of thousands of tonnes per year, but the project is achievable on an industrial Mars. If industry is able to generate surplus cash from exports, it will probably happen.
If an abundant water supply is available, it would not surprise me to see covered crater lakes relatively early in the colonisation effort. Crater lakes could be productive ecosystems growing food for a colony, processing wastes and providing a radiator for waste heat. The vapour pressure of water is only about 1KPa at 10C and Mars ambient is 0.6KPa, so it may be easier to build a crater lake than a greenhouse. A transparent floating cover would be sufficient to prevent boiling. Under 10m of water, pressure would be 380mbar. A habitat could therefore be located within the lake with proper buoyancy control. This would take care of meteorite and cosmic ray hazards, while allowing heat leakage to contribute to the lake ecosystem. Instead of an airlock, the internal air pressure of the hab can be balaced against the column density of the water. A pressure-suited individual could enter the water and swim to the surface.
Again, escaping water vapour is a greenhouse gas and decaying vegetation will release methane which is also a greenhouse gas.
A Venus cloud colony would be difficult to maintain, for several reasons. The buoyancy of air in CO2 gas is only 1-2kg/m3. That's a problem if this city needs industrial infrastructure of any kind. The city would be exposed to anhydrous sulphuric acid, for which only a few materials are capable of long term resistance. Worst of all, it is at the bottom of a deep gravity well. Importing or exporting anything is therefore almost as difficult as it is on Earth. I cannot see how it would actually work economically.
Last edited by Antius (2016-12-06 17:15:25)
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If we do not live where we would see a rotating clock with the rise of the sun for a 24 hour process as we will still be supplimenting that with artificial lighting or a means to simulate its effect from a constant sunshining by using a blinding system to cause shadows to total darkness to happen at whatever interval we want....
Heat, atmospheric pressure and quality of air we will breath as well fall into the balance of we will be simulating what we know to allow a comfortable existance on either planet and its how we get to this that will be different.
Energy is the greatest difference from the start for both as venus recieves to much as compared to Earth while mars recieves to little. So this will alter how we will approach the creation and use of it to achieve that same level of comfort that we are accustomed to having.
Growing food will be equally challenging and different for both but in the end it is still food that we can eat every day within the limits of resources.
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Regarding gravity, in terms of walking around on Mars we can replicate one G by wearing weighted suits and boots that will require to expend the same amount of energy for us to take steps on Mars as on Earth. Mars is by a Long way the best candidate for terraforming. Terraformatiom will take a long time - probably hundreds of years - but long before that we will see large pressurised spaces - glass domes, low rise inflatables and covered gorges bursting with flora and fauna.
Last edited by louis (2016-12-07 05:41:05)
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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Quote:
Mars is by a Long way the best candidate for terraforming. Terraformatiom will take a long time - probably hundreds of years - but long before that we will see large pressurised spaces - glass domes, low rise inflatables and covered gorges bursting with flora and fauna.
And;
http://newmars.com/forums/viewtopic.php?id=7556
Last edited by Void (2016-12-07 15:55:49)
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The hydrogen, by far. The Earth's oceans are kilometres deep. The atmospheric mass is about 2 orders of magnitude less, though still enormous.
You come up with some interesting ideas, but you appear to lack engineering judgement. You find it difficult to judge the scale of what you discuss and guage its practicality. Yet you seem capable of doing the math. Everything we discuss here is far out, mind you.
Exactly the point, we won't live to see any of it happen, unless we get nanotechnology and indefinite life extension. I think some underestimate the difficulty of terraforming Mars. Venus by the way would have shallower oceans than Earth, and much of the mass for its oceans would come right out of its atmosphere, after all carbon dioxide is mostly oxygen, each oxygen atom requires two hydrogen atoms to make a water molecule.
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Venus and Mars are now in mutual reception. I’m curious to hear what others think of this. To me, it seems that they would both be weakened. In general, I’d say that Venus attracts and Mars attacks. If they perform opposite roles, they’d do it all wrong. I haven’t thought enough about this and have done no research, but maybe some of you have. If so, I’d like to know what conclusions you have come to about these two bodies in mutual reception. How does one best deal with issues that come under their influence during this time?
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Venus closely resembles a biblical description of hell. If its temperature and atmospheric pressure are reduced through use of a sun shield, colonisation may be possible. But would it ever be desirable? The planet has very little hydrogen. It also has a deep gravity well, that makes escape impossible. A terraformed Venus would be a dry Vulcan. Mars does not have these problems.
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I used to think Venus was a better candidate. Venus has 90% surface gravity, 90% as much surface area as Earth, and 90 times atmospheric pressure. It's a rule of 90s. Mars can be terraformed, but you can't increase gravity.
Mars is cold, Venus is hot. Mars can be terraformed by chemical/mechanical means, Venus by biological means. Mars has practically the same length of day and axial tilt as Earth, while Venus has an extremely long day and practically no axial tilt.
Current technology means Mars is easier to settle and terraform. However, I've posted before that a modification of Carl Segan's idea to terraform Venus would work. He wrote a paper in 1961 suggesting seeding the clouds with algae. At that time Venus was thought to have a 6 bar surface pressure; it would have worked if that was true. But Venus has 92 bar surface pressure (90 times Earth's 1.01325 bar). It will still work, but requires genetically engineered anaerobic archaea that will produce polyanhydride to sequester the bulk of CO2 from the atmosphere. And Venus will require carefully engineered clouds to cool the planet.
Mars has plenty of ice. Ironically, people thought Mars was a dry desert while Venus was dripping wet due to its cloud layer. It's ironic because we found plenty of ice on Mars, but Venus is extremely dry. All water of Venus is in its clouds. Venus may require a comet to deliver more water.
Mars has enough dry ice to produce an atmosphere. Pressure will be lower than Earth, but enough for humans to walk outside without a spacesuit. Mars has air, water, but lacking nitrogen. Unless we find vast deposits of underground nitrate somewhere, Mars has a problem. Venus has 6 times the mass of nitrogen in the atmosphere as Earth. Some will be consumed by life, producing protein and DNA, but still Venus has plenty.
Mars can be settled now using spacesuits and pressurized habitats. A far better spacesuit would be MCP. Venus could be settled using a hard suit, based on Newt Suit. Such a hard suit keeps pressure out. A Mars settlement or suit has to keep you warm, a Venus settlement or suit has to keep you cool.
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There is insufficient water in the atmosphere of Venus to sustain an algal population. Also, plants need minerals to grow.
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There is insufficient water in the atmosphere of Venus to sustain an algal population. Also, plants need minerals to grow.
That's what genetic engineering is for. Halobacteria use retinal as their primary photodye, not chlorophyll. Retinal is composed of carbon, hydrogen, oxygen, and nitrogen (CHON). It has no minerals at all. DNA is composed of CHON and phosphate; there's phosphoric acid in the atmosphere of Venus. Cell walls are composed of bilipid membranes. Lipids are CHO, phospholipids have a phosphate head bonded with a glycerol molecule. Glycerol is also CHO. So with phosphoric acid, CO2, nitrogen, and water the organisms have everything they need for simple proteins, photodye for photosynthesis, cell membranes, and DNA. The job is then to go through the entire proteome to only use elements available in the atmosphere.
Like I said, genetically engineered anaerobic archaea.
Last edited by RobertDyck (2017-08-19 16:16:15)
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I don't see either being "fully terraformed", in the sense of having a breathable atmosphere for baseline humans, anytime this millenium, if ever. However, I think it would be possible for there to be an advanced biosphere on Mars, particularly in the seas, with enough oxygen in a thick enough atmosphere that it would be possible to walk through taiga forests with a backpack device for extracting oxygen from the atmosphere, and large domed areas with a breathable atmosphere. On Venus, I think we should just dump a lot more water into the atmosphere and build floating habitats. Maybe in time we could have greenery growing on the outsides, and some oxygen in the atmosphere for higher plants and maybe even insects.
Use what is abundant and build to last
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Venus has a thick atmosphere of carbon dioxide. Frankly, how could Mars atmosphere after terraforming trap heat loss and keep solar energy inside the atmosphere? And Martian atmospheric particles would react with solar wind particles towards Mars to transmute into new chemical elements or the energies of these particles would be dissipated to the atmosphere?
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http://wiki.gekgasifier.com/w/page/6123 … n%20Gasses
Common "molecular weight"
Nitrogen N2 28.02
Oxygen O2 32With very little of these in earth air:
Methane CH4 16.043
helium (MW 4)
hydrogen (MW 2)
neon (MW 20)
Ammonia (MW 17)But for mars and venus we have lots of
Carbon dioxide CO2 44.01With the Mars UV level we will not have much of these and that is one reason why we do not have a breathable atmosphere for mars
Ozone O3 48.0
Sulfur Dioxide SO2 64.06
Sulfuric Oxide SO 48.063
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The loss of atmosphere that would take place under current Mars conditions would be over tens of thousands or even hundreds of thousands of years. You need to read up on it. It doesn't happen over night. Certainly if we created an Earth-analogue atmosphere on Mars we wouldn't have to worry about losing it for a very long time, during which we would find technological solutions as to how to retain it.
Venus has a thick atmosphere of carbon dioxide. Frankly, how could Mars atmosphere after terraforming trap heat loss and keep solar energy inside the atmosphere? And Martian atmospheric particles would react with solar wind particles towards Mars to transmute into new chemical elements or the energies of these particles would be dissipated to the atmosphere?
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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Everything I have read leads me to the view that we could terraform Mars into a breathable atmosphere within 200 years. It depends partly on what you are prepared to do. Some people might not like the idea of seeding the polar caps black. Nuclear bomb explosions (above and below ground) might not be everyone's cup of tea. And maybe people don't want to spend trillions of earth based dollars on creating greenhouse gas factories on Mars. But it is definitely doable technically in my view.
I don't see either being "fully terraformed", in the sense of having a breathable atmosphere for baseline humans, anytime this millenium, if ever. However, I think it would be possible for there to be an advanced biosphere on Mars, particularly in the seas, with enough oxygen in a thick enough atmosphere that it would be possible to walk through taiga forests with a backpack device for extracting oxygen from the atmosphere, and large domed areas with a breathable atmosphere. On Venus, I think we should just dump a lot more water into the atmosphere and build floating habitats. Maybe in time we could have greenery growing on the outsides, and some oxygen in the atmosphere for higher plants and maybe even insects.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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If we want an earth layered atmosphere we will need a means to not only build up oxygen but nitrogen as well but its the upper layers that will need to be different as ozone will not work as the level of uv would distroy it so we will need something above that.
Something that Maven found was Mars’s atmosphere hosts metal layers that shouldn’t exist
The space between planets is full of metallic dust and rocks. As they are drawn into a planet’s atmosphere, they burn up, leaving behind metal particles like iron and magnesium. On Earth, the behaviour of those particles is mostly controlled by the planet’s strong magnetic field. They use magnetic fields as a sort of highway, and stream along the magnetic field lines to form thin layers throughout the atmosphere.
But Mars has no such field. The planet does have small regions with weak magnetic fields in its southern hemisphere, but without a global field like Earth’s, it should not be able to form the layers that MAVEN sees.
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