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What if the goal were more modest, say to add 7mb of O2 and 15mb of CO2 (from carbonates - I'm fairly sure they exist)? During which time we also turn our orbiting death star on the northern ocean, to saturate the atmosphere with water vapour and to melt the ocean.
Use what is abundant and build to last
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I'm not sure that is the only process to get oxygen out of regolith.
This refers to an experiment with "lunar" soil.
http://science.nasa.gov/science-news/sc … moonrocks/
Seems to be a simply case of heating the soil and no more which means, perhaps your figures are overestimates? Of course how you achieve that heating may be an issue. Creating the lens should be possible, given the prevalence of silica on the surface.
Ideally one would envisage a system where you had a few robot factories around the planet producing a very simple, slowing moving solar powered rego-melter robot. Let's say they are producing 10 million and rising per annum, or 100 million per decade or one billion per 100 years, allowing for scrapping of redundant vehicles.
We already have way more than a billion motor vehicles on Earth. So this is in the realm of the doable. It might take a 100 or 200 years for the Mars community to gear up to such production but it is not impossible. The evidence suggests that autonomous robots will be a commercial reality v. soon. So you can imagine a scenario in the next 50 years where you might land say 10,000 robots over a period of a couple of decades that then mine the iron ore and other materials which are then used to construct the robot factories and continue to operate those factories producing the robot rego-melters that are then taken to high concentration hematite or basalt fields to do their work.
That said, I don't think terraforming will be our no. 1 priority - science, exploration and settlement will be I think, so terraformation may follow a little later.
I did some calculations to examine the potential for extracting oxygen from Martian rocks. The easiest substance to reduce is Iron III oxide, which thanks to the long term presence of water on Mars, is available in abundance, giving the soil its rusty colour.
The mineral hematite (Fe2O3) can be reduced by heated to 1400C, at which point it reduces to Fe3O4 (Magnetite). The reaction is written like this:
3Fe2O3 = 2Fe3O4 + ½ O2
The energy cost of this step of this reaction is 14.8MJ per kg O2. Next, the magnetite can be reduced to pure iron by hitting it with hot CO:
Fe3O4 + 4CO = 3Fe + 4CO2
The energy cost of this reaction is 17.2MJ/Kg O2. Other reactions, such as reduction of silicon dioxides and aluminium and magnesium oxides are possible, but the energy cost is much higher.
To add 70mbar of oxygen atmosphere to Mars through direct regolith reduction would require total energy of 4.2E18 MJ. If it were done over a 100 year period, that would equate to a power requirement of 1.33billion megawatts (i.e. equivalent to 1million modern day nuclear power reactors – or more likely, 100 extremely big nuclear power reactors built at the poles). I wonder if there is enough fissionable material on the planet. To do the same using solar PV power would require a circular solar power satellite some 4000km is diameter. Fusion reactors would probably work better at that scale.
The total mass of oxygen needed is 2.6E17 kg. About 3kg of hematite would be needed to produce 1kg of oxygen. Assuming it exists in rock / regolith at concentrations of 10% by weight, about 30kg (10 litres) would be needed to produce 1kg O2. To produce the entire 70mbar atmosphere, some 2.6E15 m3 of rock and soil must be reduced. That is equivalent to a cube 138km aside, or a 1000km x 1000km mined to a depth of 2.6km.
I think it could be done if Mars were to become the industrial steel producing capital of a future solar system. The process would easily release enough steel and glass to para-terraform the entire planet, which would probably have happened anyway by the time a future Mars had mustered the resources for such a huge industrial effort.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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Louis, I suggest you do the calcs. It will give you a better idea as to what is likely to be practical and what is not. Many emotionally attractive options completely wither when exposed to hard arithmetic.
Heat any oxide to a high enough temperature and it will dissociate. The most energetically easy (abundant) metal oxides to dissociate are those of iron, especially at the higher oxidation states. That’s why most lunar oxygen production techniques focus on ilmenite, iron titanium oxide. Hence also my example with hematite. Breaking chemical bonds comes at a certain energy cost. Some processes are more efficient than others, but there is a baseline energy cost that you simply cannot get around. It is measured in megajoules per kg. This shouldn't come as much surprise, as we are effectively reversing combustion. The heat of combustion for air burning with a wide range of fuels is about 3MJ/kg. Since oxygen is about 23% air by weight, its heat of combustion is ~13MJ/kg. That is the about the bare minimum energy cost that we can expect to pay when extracting oxygen from an oxide. And remember, any feedstock requires energy to gather it in the first place and will contain residual heat when you finish with it, so in reality you looking at more than the bare minimum.
The amount of power you need depends upon how long you are willing to wait and how much oxygen you want to produce. I chose 70mbar because that conveniently brings you up to the Armstrong limit when added to the existing atmosphere. The surface of Mars receives a time average solar flux of about 140W/m2 (ignoring atmospheric absorption). If you covered Mars with 20% efficient PV cells, you might just about generate enough power to do that in 100 years. If your robot rovers are numerous enough to cover 10% of the planet’s surface area, then you might do it in 1000 years. You would also need more robotic rovers to collect the reduced iron slag and corral it. In fact you would need to mine the entire planet to a depth of 20m. That should give you some idea as to why solar powered robot ovens aren’t going to cut it. They may be a useful tool for mining the material, but you need something with a lot more guts to actually heat and reduce the ore. Bottom line is you need lots of very cheap electricity. Do we have any contender technologies capable of doing that?
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I like to see you guys going at it. It is sort cliché thing to mention, but very real, Phobos & Demos. What does the shell world guy think about that and solar power.
They may be embedded with ice or not, but some materials there. Going to all the effort to cook up an atmosphere for Mars, I would think that Phobos and Demos would just be easy.
And maybe get some shell worlds, and maybe point a terraformer death star at the northern hemisphere ocean.
Personally I would go for the south pole ice cap, since a river ending in Hellas would offer the chance of a sea with the most maximized air pressure early on.
https://www.quora.com/Are-the-moons-of- … lonization
Last edited by Void (2015-11-12 15:15:23)
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Antius thanks for the page 1 calculations and on this one as well. I am going to add that we can also do a hydrogen reduction as well.
A LABORATORY STUDY OF THE REDUCTION OF IRON OXIDES BY HYDROGEN
Magnetite forrnation by the reduction of hematite with iron under hydrothermal conditions
These would mean using less energy to do the processing but with a boil off of the water and then more energy to release the oxygen from the newly created water that will form.
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Kind of lonely around here just now Spacenut.
My communications on this thread have only been to indicate that we should not despair about the results of Marvin. (Could correct this to Mavin, but Spacenut might prefer that I leave my mistake )
Notable to me is that Antius confirmed that while a part of the atmosphere of Mars was being swept away by the solar wind, there would have been a transition period where a great part of the Hydrosphere, and also large parts of a atmosphere would be solidified by increasing cold, as a condensate collection. This seems to support some other evidence that in fact the rift valley and the northern hemisphere are in part having massive amounts of ice under their apparent dirt floors. Antius also indicated that he thought that CO2 should have collected as an ice buried under water ice and dust and volcanic ash sediments. In fact their could be liquid CO2 at this point where CO2 Ice may have been warmed up. I also believe that if during that transition period, hypersaline lakes existed, there should be Nitrous Oxide as well, and Clathrates of it and CO2.
Some time ago, I remember suggesting shooting ice into the upper atmosphere of Mars, where it would vaporize due to drop in pressure, and lack of humidity. Doing it on the daytime side I presume would also add the heat of the sun to vaporize it.
This met with some horror from our good terraformer at the time, and he might have been correct for the Mars we supposed, but now if it is proved that their might be as much as say 1/2 mile of ice total to cover the whole planet, or much less, I think such objections might be allowed to pass.
We hate the "Loss" of atmosphere from a planet in this case, but, it is simply nature. In the end the mass is not lost, it is still in the Universe, Galaxy, Solar system.
So, give up some Hydrogen, and maybe a little Oxygen.
Of course what I am hoping to do is to tap into the usually hated U.V. flux. It should be hideous at high altitudes on Mars, and it should rapidly split the water vapor that ends up in the upper atmosphere. So now you have turned it into your power source.
Due to low atmospheric pressure and low gravity .38 g, as Antius has stated ballistic trajectories are more favored than on Earth. So make your ice cannons and shoot ice slugs up in such a manner that the ice slugs will rapidly rise above the lower atmosphere where temperatures and pressure can allow the vapor to condense, up where especially in the sunlight, the ice will rapidly vaporize. Just on a guess. Lets think about a pressure of .01 or .1 mb, in full sunlight. It almost has to become vapor, and the U.V. will be very hostile to it and will tend to shred it into Hydrogen and Oxygen. The Hydrogen will preferentially float away and preferentially be stripped away by the solar wind, tending to leave behind more Oxygen, and tending to build up the Oxygen content.
In order to do this we will have to have melted reservoirs of water, perhaps in a manner suggested by GW or myself. Various options are available. Mr. GW's ideas are very rugged, and may often be preferred.
Reservoirs of water have shelter and other advantages to offer.
Anyway, I have thought of yet a new wrinkle on this that I had not previously entertained.
While much of the Hydrogen will quickly be lost, perhaps a small amount of Hydrogen will filter down to the lower layers of the atmosphere as a dissolved gas. If so, I can see the opportunity to use reverse osmosis to get it out of the atmosphere it could be a minor component just as CO is. However being much smaller than CO2, CO, O2, and N2, it should respond to reverse Osmosis much better.
Now if you have got that, you can inject the hydrogen into your liquid water reservoirs, and microbes will extract Oxygen from Oxygen containing Sulfur compounds, if that is a trick you like.
But should you prefer, perhaps you might also add Martian atmosphere to the water, the CO2 might supply Oxygen for micro-organisms to life off of. Of course the atmosphere also contains small amounts of O2 and CO which would be a bit of a contribution as well.
Further, if indeed, you might harvest Hydrogen from the atmosphere by the previously mentioned methods, then of course I would think you can have fuel cells that run off of H2 and CO2, and also maybe even internal combustion engines.
So, the point being that this could be a method to turn a very bad enemy of life on Mars, U.V. into a helper.
Further thoughts:
1) By pushing water vapor into the upper atmosphere, it is possible that you could scrub Chlorine out of the atmosphere. Chlorine wrecks Ozone.
2) It is possible that you might put an intensified O2 layer above the normal atmosphere of Mars, and that could develop some Ozone, even if the lower atmosphere was still dominantly CO2. However, I would think it would not be very strong, but something is better than nothing.
3) If #2 were true, and you did get an Ozone layer, then you will have to fling your ice bullets above the Ozone to keep the process going.
Anyway perhaps a aboitic pathway to a Martian biology, and a usfull assist to the habitation of Mars by humans.
Null & Void
I hope this will be fun.
P.S.
Just throwing this in also. I was looking for Sulfur compounds on Mars, and found this. The video is long, but interesting, involves brine on Mars, and NASA.
http://www.engadget.com/2012/12/03/nasa … -analysis/
Last edited by Void (2015-11-14 09:13:59)
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I have had a good chuckle as Marvin is and Maven is but whats a Mavin...ahh a typo....I make lots of those.....along with other misspelled words.....
Mars does seem to have a reserve of gasses that are locked up due to the cold and gravity. Simply warming the planet to release them would be easy but to what end if we still need a space suit to go outside on the surface....That said we need to build an atmosphere that not only will be thick enough for man to breath but protective enough to allow man to roam the surface free of the space suit.
I think that you are correct about water vapor in the atmosphere freezing and ouch comes to mind if its anything like golf ball size when it comes back down.
I did recall the there were experiments with UV breaking down water but only found disinfecting of what but happened on this other method Solar electrolysis via catalysts
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Spacenut said:
I think that you are correct about water vapor in the atmosphere freezing and ouch comes to mind if its anything like golf ball size when it comes back down.
Therefore the helmet
Last edited by Void (2015-11-13 19:01:05)
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In light of the recent conversation, I revive this information:
http://nextbigfuture.com/2015/01/graphe … llect.html
http://spectrum.ieee.org/nanoclast/gree … y-from-air
These article dated 2015 appears to support the notion that this idea is still considered fact supported by apparently notable people out there in science and news land.
https://fuelcellsworks.com/news/graphen … e-spectrum
http://www.mnn.com/green-tech/research- … -fuel-your
If this turns out positive, then imagine a Mars, where coupled with the disintegration of water through U.V., a Hydrogen content is fostered as a dissolved minority gas, but is retrievable at will from the Martian atmosphere.
Graphene breakthrough could make it possible to fuel your car with air
Graphene membranes could be used to 'sieve' hydrogen gas from the atmosphere to then generate electricity, say Nobel Prize-winning researchers.
By: Bryan Nelson
December 1, 2014, 10:38 p.m.Graphene
Graphene's structure is an atomic-scale honeycomb lattice made of carbon atoms. (Photo: Wiki Commons)The Nobel Prize winners for graphene research, Andre Geim of Manchester University and colleagues, have revealed a new application for the ultra-thin, ultra-strong material that could revolutionize fuel cell technology and open new doors for generating clean energy, reports Reuters.
Graphene, which was first isolated in 2004, is the thinnest material on Earth at just one atom thick, and is 200 times stronger than steel. It is impermeable to all gases and liquids, making it extremely useful, and its discovery paved the way for everything from corrosion-proof coating to super-thin condoms.
In their latest research, Geim and his team have also shown that this super-material could potentially be used for "sieving" hydrogen gas from the atmosphere, for the purpose of generating electricity. The finding could make hydrogen fuel cells more viable than ever before, and even make it possible to collect fuel right out of the air.
"We are very excited about this result because it opens a whole new area of promising applications for graphene in clean energy harvesting and hydrogen-based technologies," said Geim's co-researcher on the study, Marcelo Lozada-Hidalgo.
Though graphene is impermeable to even the smallest of atoms, Geim and his team found that protons, or hydrogen atoms stripped of their electrons, were nevertheless capable of passing through the material. This was especially the case when the graphene was heated and when graphene films were covered with platinum nanoparticles, which act as catalysts.
Basically, this means that graphene could potentially be used in proton-conducting membranes, which are essential components of fuel cell technology. Graphene would be a superior material for these components because it does not leak — a common problem with membranes made of other materials — which would greatly improve efficiency.
Perhaps even more remarkable, however, is that this latest breakthrough means graphene membranes could be used to extract hydrogen straight from the atmosphere. When combined with fuel cells, this technology could make it possible to make mobile electric generators powered just by the tiny amounts of hydrogen in the air.
"Essentially, you pump your fuel from the atmosphere and get electricity out of it," Geim said. "Our (study) provides proof that this kind of device is possible."
This would make cities in Lava Tubes for instance and other underground methods of habitation much more habitable, since you would then not be required to work with solar arrays on the surface. And the output from fuel cells would include some water I think, so you could then have those contributions to life support at almost any location on Mars, without the costs of the normal methods of supply of life support.
Caves with artificial light with normal pressurization with agriculture. This would provide a minimization of the need for hard to procure materials such as transparent glazes, Copper/Aluminum which might otherwise be needed to have surface greenhouses or electrified underground greenhouses.
You could simply separate the Hydrogen out on the surface, and pipe it down, and likewise pipe down some atmosphere as the Oxidizer.
Piping could be of Steel or Plastic. (Maybe plastic needed for the Hydrogen due to embrittlement issues). (I am trainable GW).
So by adding water to the upper atmosphere of Mars, perhaps very conveniently turning it into a abiotic (I can use fancy words), solar cell.
One giant solar cell that is abiotic, but it's output can be input to a biotic system. (And provide electric power as well).
Now that's fantastic if possible. And at the same time you would be building up both the Oxygen percentage of the atmosphere, and the bulk of the atmosphere.
I think shooting ice into the upper atmosphere of Mars could be the most effect method to get good results. I could be wrong, but I think up there, above the maximum height where water normally cycles in the atmosphere, it must be incredibly dry. So ice of a proper size, moving at speed shot though that air and also subjected to daytime sunlight should sublimate very quickly. The trick will be to keep it from sublimating away during it's trip through the lower layers of atmosphere. (It shouldn't be that hard, to get some of it up higher, I am speculating).
Perhaps if you could generate an artificial dust devil you could "Funnel" water vapor to higher altitudes. Water vapor is certainly lighter than a CO2 dominated atmosphere, so it seems possible to me. Don't know if it would get high enough and stay high enough long enough to make it worthwhile though.
One giant Mars sized abiotic solar cell.
Last edited by Void (2015-11-14 09:46:03)
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Oh well, now I am imagining myself on the surface of Mars, a water spout rising so high in the sky that I have to tip my head back.
The method to produce it;
-A melted reservoir or a river induced from an ice body such as the southern ice cap.
-Instead of photocell, rather simple solar concentrating mirrors. Perhaps a solar tower with heliostats.
In the case of an ice covered reservoir as the source of water, some steam is shunted back to it to melt it bigger.
Most or all of the rest of the water is simply vaporized in the tower, turning turbines with superheated steam, and released. Of course except for twinkle you would not be able to see the steam until some portion of it began to condensate into ice particles or in a denser atmosphere droplets. Those however rather than dropping to the ground would more than likely be sucked up in the vortex.
The steam is lighter than Earth Air even if not superheated. Martian air is about twice as heavy as Earth air of the same density, so that superheated steam should lift of bigtime, headed for the high sky. It will cool down rather quickly due to radiation, but it should still be quite light relative to the normal Martian atmosphere. Even when the vapor mixes with the Martian atmosphere high up and creates a relatively normal temperature high humidity mix, it should still be lighter than the surrounding Martian air, unless some portion should accumulate a condensate which would almost have to be ice particles or supercooled droplets. However if it is occurring in sunlight, I think it unlikely that the moisture would snow down. Most likely you would get a high atmospheric plume enriched in H20 vapors, which the U.V. would break down into Hydrogen, and Oxygen variations.
But I like that vision, the water spout rising from a solar heated tower.
Of course you would have to winterize the tower to some degree every night to prevent freeze damage.
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So this method of terraforming might be called Promoted or Induced Photolysis
http://arxiv.org/abs/1403.2713
https://geosci.uchicago.edu/~rtp1/paper … 2-2014.pdf
http://www.astrobio.net/news-exclusive/ … -for-life/
The researchers investigated water photolysis, which happens when a water molecule is torn apart by high-energy photons from the sun. Usually the water (two hydrogen atoms and an oxygen atom) is broken into two parts, OH and H. The H escapes to space because it is so light. Over time, more oxygen molecules build up until eventually O2 (molecular oxygen) form as well. - See more at: http://www.astrobio.net/news-exclusive/ … KpWJg.dpuf
And here is a related method which might suit the surface of a planet. Perhaps a sea. For instance if you had a method to force melt parts of the southern ice cap, and make a river run into Hellas, even with a nasty U.V. flux on the surface of the water, you might put floating "Bobbers" in the water, which would be coated with Titania.
Photolysis on the surface of planets:
http://www.nature.com/articles/srep13977
So, here is a catalist
The search for habitable exoplanets in the Universe is actively ongoing in the field of astronomy. The biggest future milestone is to determine whether life exists on such habitable exoplanets. In that context, oxygen in the atmosphere has been considered strong evidence for the presence of photosynthetic organisms. In this paper, we show that a previously unconsidered photochemical mechanism by titanium (IV) oxide (titania) can produce abiotic oxygen from liquid water under near ultraviolet (NUV) lights on the surface of exoplanets. Titania works as a photocatalyst to dissociate liquid water in this process. This mechanism offers a different source of a possibility of abiotic oxygen in atmospheres of exoplanets from previously considered photodissociation of water vapor in upper atmospheres by extreme ultraviolet (XUV) light. Our order-of-magnitude estimation shows that possible amounts of oxygen produced by this abiotic mechanism can be comparable with or even more than that in the atmosphere of the current Earth, depending on the amount of active surface area for this mechanism. We conclude that titania may act as a potential source of false signs of life on habitable exoplanets.
Last edited by Void (2015-11-14 17:09:43)
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I suppose it's possible, provided there is indeed sufficient water. The amount of solar energy hitting Mars is equivalent to about a million large nuclear reactors. If it were possible to suddenly hydrate the upper atmosphere then solar UV light would dissociate the water into oxygen and hydrogen. It would take millennia to build up a breathable atmosphere but that is a short time in the life of the solar system.
But at the back of my mind is always this. Human beings cannot even agree to limit CO2 emissions into the atmosphere of their home world. Maybe I'm being cynical, but is it realist to expect those same people to invest in a project that might produce results centuries after their deaths?
Last edited by Antius (2015-11-14 17:18:34)
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Actually, I think possibly yes.
And in the shorter term, perhaps you get a contribution to an atmosphere which;
1) Will as you have specified better protect humans from radiation.
2) Perhaps provide an Ozone layer, allowing simple life on the surface such as Lichen, Cyanobacteria, and Algae.
3) If it works then a small amount of H2 dissolved in the atmosphere, which may be retrieved, to run underground life support functions for humans.
4) Also, no reason not to have a underground mega-city in the northern hemisphere.
That's actually quite a lot, I think.
From this perch, perhaps missions to the stars.
Anyway, make sure there are dreams with at least some credibility for the young who will follow.
Yes, have a bit of faith.
There exists the potential of plenty of creative people who will follow in time beyond our shadows. People who might solve even more.
The other choice is to sit in a hole and pull the dirt over us.
Actually dumping the water superheated to the atmosphere would be a selfish action, to generate power desired in the time of the people wanting it. The vapors going into the upper atmosphere would not bother them. The H2, a small fraction coming back down by being mixed and dissolved, would also suit their needs. As you say, if there is enough water as ice then it could be done, and they would do it to suit their immediate needs and desires. The improvement in atmospheric density as a side effect should also suit their preferences, since as you pointed out earlier, it is at least a greater radiation protection for them.
Also, the more dense the atmosphere, the easier to pump it into your habitat for your use. If a small amount of H2 is harvestable, then you can have just about anything you want from that.
The required water I believe would be 32/5 on Earth (And compensation for the Hydrogen), so about 6.4 feet, round that to 7 feet. On Mars then you need 7/.38 perhaps? 18 feet of water over the whole surface of the planet. 18 * 1.1 for an approximation of pure ice. So, 20.25 feet of ice over the whole surface of the planet, where the O2 is released, and most of the Hydrogen is either in a tenuous layer above that, or has been swept away by the solar wind.
I am not the best at math, so correct me if I am far off. It is late as well.
I estimate that their could be about 1/2 mile of water to cover the whole planet, if the rift valley has the ice speculated on for it. If it does, and the northern hemisphere has similar, then that is actually an underestimation.
We might be disappointed, but I have found regularly that the situation on Mars and the Moon are constantly being upgraded from an estimation of total desolation that was formed perhaps in the 70's.
If it turns out that there is not enough, then still 22 mb of O2 is better than 6mb of CO2 in my estimation.
OK, that comes a bit short, 200 mb of O2 would be enough Oxygen, but perhaps not enough pressure, but it is getting close.
I anticipate that their would be a contribution from other sources, or if you like make the ice 30 feet think, then OK perhaps.
The real thing I am after is the O2 atmosphere, and the H2 availability from the action of the UV. That by itself even without sufficient pressure, will be enormously good for the habitability of the planet.
Last edited by Void (2015-11-15 00:10:15)
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Some people are apparently disappointed that there can be worlds with Oxygen in their atmospheres where life does not exist. I am excited for it.
Imagine crossing the gap between stars to a terrestrial planet with O2 in it's atmosphere, and perhaps N2 as well, and no life.
A much better prospect perhaps than it might otherwise be.
So far speculation on it is for habitable zone planets, but I bet, if a planet is warm enough to evaporate H20 vapors from ice, and then can have ice crystal clouds, it can then also even perhaps more slowly generate O2 in it's atmosphere.
For me this is a great concept, since then we have far better chances of finding terrestrial planets suitable for settlement, even if they are rather cold. If Mars had a magnetic field still, if it was the same size as Earth, it very likely would have a thick atmosphere with O2 in it, I think, as a thicker atmosphere would lead to more of a greenhouse effect and more of a greenhouse effect would lead to more H20 evaporation, and that apparently would provide more O2.
Last edited by Void (2015-11-15 00:18:51)
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Imagine crossing the gap between stars to a terrestrial planet with O2 in it's atmosphere, and perhaps N2 as well, and no life.
We know one. Mars atmospheric composition - measured by Viking 2 lander
Carbon Dioxide (C02) 95.32%
Nitrogen (N2) 2.7%
Argon (Ar) 1.6%
Oxygen (O2) 0.13%
Carbon Monoxide (CO) 0.07%
Water (H2O) 0.03%
Neon (Ne) 0.00025%
Krypton (Kr) 0.00003%
Xenon (Xe) 0.000008%
Ozone (O3) 0.000003%
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Good to hear from you. RobertDyck said:
Void wrote:
Imagine crossing the gap between stars to a terrestrial planet with O2 in it's atmosphere, and perhaps N2 as well, and no life.
We know one. Mars atmospheric composition - measured by Viking 2 lander
Carbon Dioxide (C02) 95.32%
Nitrogen (N2) 2.7%
Argon (Ar) 1.6%
Oxygen (O2) 0.13%
Carbon Monoxide (CO) 0.07%
Water (H2O) 0.03%
Neon (Ne) 0.00025%
Krypton (Kr) 0.00003%
Xenon (Xe) 0.000008%
Ozone (O3) 0.000003%
Now you made me think I can think
Some of my earlier schooling included concerns for process control, and in the mines, process control was just about everything. Although electronics were also involved, feedback relationships were key for me to understand what was going on.
Not exactly the seed of the thought, but what if Venus, Earth, Mars, and Titan all had in a certain way similar initial mix. Similar, not the same. I am thinking that Venus would have started with the least amount of hydrocarbon greenhouse gasses, and Titan the most.
I that distribution was proportional, then Mars would have started with as a percentage of mass more hydrocarbons than Earth.
This is not so unlikely to think anymore. It used to be thought that Earth was a dry hot ball, and that comets brought in water. This is very disputed now. I believe some research on Baffin island in Canada indicates that Earth started with water. It also would have Carbon, and so why not Hydrocarbons.
This would explain how both the Earth and Mars could have liquid water early on when the sun was much dimmer.
So, Terrestrial planets and (Titans) would start out as reducing, but in time Photolysis would alter them. You could call it an aging or maturing process. Factors that would help them to mature to Oxidizing natures would be size and magnetics. Both help a planet to be selective about what it allows the solar wind to take away.
In the case of Venus, apparently it's mass is sufficient to hang on to enough Oxygen relative to Hydrogen that it became Oxidized.
It does in fact loose N2 and O2, but at a much lower rate than the loss of H2 generated. Venus would have aged much faster than Earth I presume due to smaller mass, and apparently less magnetic protection, and of course twice as much U.V.
The Earth being even larger and still having a full magnetic field, the solar wind does not get much of a chance to pull away Oxygen. However Hydrogen bouncing on the top of the atmosphere and in the magnetic field perhaps gets lost to space.
Mars leaks O2 and N2, since it's gravitation is low. When it had a magnetic field however, that might have compensated rather well. Up to the point that Mars lost it's magnetic field, perhaps it was aging at a slower rate than Earth. It would have 1/2 the U.V. more or less of the Earth.
I am going to guess that it is possible that Mars had a reducing atmosphere up to the loss of the Magnetic field, and then rapidly changed to a Oxidizing atmosphere, and then when the protective layer of Hydrogen above was swept away the solar wind dug into the Nitrogen and Oxygen and swept much of that away also, and then the atmosphere became too thin to protect open water, so any lakes, seas, and Oceans froze up. Before the end of the freeze up, most CO2 solidified, and also if ice covered hypersaline lakes existed, some Nitrogen was sequestered.
I havn't been able to figure out exactly how the present Martian atmosphere maintains itself, but things I have read, indicate that at the top of the atmosphere, CO2 splits, and the CO is retained and Oxygen lost to the solar wind. The water ice on the planet apparently is the source of makeup Oxygen. During that process of the photoysis of the water, the Hydrogen is more quickly lost, and the Oxygen of course eventually lost.
I have wondered for some time what is the feedback mechanism that might maintain the average surface pressure on Mars at about 6 mb.
I am reluctant to guess, because my ideas seem weak. 6mb however is about the triple point of water. Quite a co-incidence.
Here is a weak proposal, but I won't bet my money on it:
http://www.ghgonline.org/otherco.htm
Other Indirect Greenhouse Gases - Carbon monoxide
Carbon monoxide (CO) is only a very weak direct greenhouse gas, but has important indirect effects on global warming. Carbon monoxide reacts with hydroxyl (OH) radicals in the atmosphere, reducing their abundance. As OH radicals help to reduce the lifetimes of strong greenhouse gases, like methane, carbon monoxide indirectly increases the global warming potential of these gases.
Carbon monoxide in the atmosphere can also lead to the formation of the tropospheric greenhouse gas 'ozone'. Atmospheric concentrations of carbon monoxide vary widely around the world and throughout the year, ranging from as low as 30 parts per billion up to around 200 parts per billion. Concentrations increased during the 20th century, but there are some signs that concentrations dropped slightly in the 1990s due to widespread use of catalytic convertors, with their lower carbon monoxide emissions, in cars.
Aside from man-made sources, a great deal of carbon monoxide comes from the chemical oxidation of methane and other hydrocarbons in our atmosphere. Additional natural sources include emission from vegetation and the world's oceans. By far the largest sink for carbon monoxide is its reaction with OH in the atmosphere, as noted previously. However, a small but significant amount is also lost from the atmosphere through deposition on the ground.
So, that's a piece of work! If the atmosphere of Mars becomes more dry, then the provision of Oxygen to the atmosphere by the photolysis of H20, is reduced, and the abundance of CO will go up relative to the amount of CO2. More CO, perhaps protects Methane, and Ozone. (Didn't know that at all). So the temperature goes up, just slightly, the evaporation of water from the surface goes up, and the atmosphere becomes more humid. That could be a part of it. Maybe.
But this is good to know. If I read that correctly, by force humidifying the upper atmosphere of Mars, and so assisting the photolysis of H20, you may induce a greater amount of CO, and promote the survival of Methane and Ozone.
Remembering Titan, I am going to speculate that given time even it might become Oxidized. Maybe a Titan analog around a very long lived red dwarf with U.V. Flares. It does have a problem of being too cold for Sublimation I believe, however, so perhaps Titan falls on the outside of a "Photolysis Zone" around stars. (Ha Ha, Habitable zone, Photolysis Zone).
But maybe Titan analogs not quite so far out. For instance would sublimation work on a "Titan" at the distance of Jupiter, if it had a 1 bar N2 dominated atmosphere?
If so, then perhaps for a very old Titan analog, an Oxygen holding atmosphere without life.
So, for alien star systems, I am interested in the "Photolysis Zone" apparently. Any planet with a N2 dominated atmosphere, and a Magnetic field, even down to the size of Mars, might also have free Oxygen, and also be lifeless. (Or life holding). Where liquid water does not lock up excess CO2 in sediments, then cold would lock it up as ice in the poles of the planet.
So you also caused me to realize that it might be ok to mix forced humidification with the aggressive use of greenhouse gasses. Since CO is helpful to preserve Methane and other greenhouse gasses, and also to promote Ozone, early on, the model could be for pressure and Ozone, and then working towards a breathable atmosphere, using both Photolysis and Photosynthesis. We might be able to have it all. However I still think it unwise to overwarm the planet. Not a good idea to overmelt the permafrost, if in fact there is as much permafrost as might be supposed. Why surrender 1/2 of the planets surface for a cold quagmire of ice and sediments trying to evolve into a cold ice covered ocean?
Last edited by Void (2015-11-15 10:42:04)
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So, I need to stop this and have a nice Sunday instead, but before I do, I will make notes on the previous.
Ozone is a greenhouse gas apparently. CO protects it from OH.
If the upper atmosphere is humidified, there could be more OH, which would unfortunately deplete CO and Ozone. However, happily the Solar wind will sweep away much of the Hydrogen, perhaps causing more Oxygen to be retained which might promote Ozone. Even happier will be if a small portion of H2 will dissolve in the atmospheric mixture and in proximity with Carbon, CO, and CO2 generate greenhouse gasses under the UV flux? Even happier if some of that H2 appears as a minority gas in the atmospheric mix on the surface.
From post #36:(Quotes from a referenced document)
In this paper, we show that a previously unconsidered photochemical mechanism by titanium (IV) oxide (titania) can produce abiotic oxygen from liquid water under near ultraviolet (NUV) lights on the surface of exoplanets. Titania works as a photocatalyst to dissociate liquid water in this process.
So, the manufacture of CO is desired, perhaps as supplement to the humidification of the upper atmosphere.
If machines are designed which can make ceramic objects from dust/sand dunes, can those ceramic objects be coated with a catalyst?
Would Titania work?
Close:
http://www.sciencedirect.com/science/ar … 7301003228
Photoreduction of CO2 using sol–gel derived titania and titania-supported copper catalysts
Then if you have a way a non moving machine, a pile of ceramic objects in the UV flux generates CO on the open surface, can you release the CO (Yes of course) but can you capture some of the Oxygen for your use? (Not critical)
Last edited by Void (2015-11-15 11:25:43)
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It will take me many days to read all the posts since my last......
The solar wind streams off of the Sun in all directions at speeds of about 400 km/s (about 1 million miles per hour).
MAVEN measurements indicate that the solar wind strips away gas at a rate of about 100 grams (equivalent to roughly 1/4 pound) every second.
https://en.wikipedia.org/wiki/Solar_wind
Solar wind pressure:
The wind exerts a pressure at 1 AU typically in the range of 1–6 nPa (1–6×10−9 N/m2), although it can readily vary outside that range.
The dynamic pressure is a function of wind speed and density. The formula is P = 1.6726×10−6 * n * V2 where pressure P is in nPa (nanopascals), n is the density in particles/cm3 and V is the speed in km/s of the solar wind.
http://www-ssc.igpp.ucla.edu/personnel/ … /mars_mag/
To date, the observations at Mars suggest that it great deal of similarity exists between near-Venus space and near-Mars space. Mars, like most of the other planetary obstacles, is preceded in the solar wind by a 'bow shock'-like structure that reflects the slightly greater than planet-size scale of the weakly magnetized Martian obstacle. The subsolar distance of the bow shock is ~ 1.5 Rm while its terminator position is ~ 2.7 Rm. Within the bow shock, the solar wind plasma is diverted around the obstacle. Within it, the imbedded interplanetary magnetic field is compressed against the obstacle nose. The field distortion associated with the divergence of the flow gives the 'draped' configuration of field lines illustrated in Figure 1.. This 'magnetosheath' is a common feature of all planetary obstacles.
Phobos 2 did detect significant fluxes of planetary ions (mainly O+, as at Venus) that had been scavenged from Mars by the passing solar wind
The observed rates of escape for the oxygen suggest that the solar wind scavenging process has the potential to remove all of Mars' present inventory of atmospheric oxygen over the next 108 years.
Mars Solar Power on the surface
http://wiki.developspace.net/Mars_Solar_Power
The quantity of solar energy striking the Earth's surface (solar constant) averages about 1,000 watts per square meter under clear skies, depending upon weather conditions, location and orientation. Part of the solar energy (55–60%) is lost on its way through the atmosphere by the effects of reflection and absorption.
https://en.m.wikipedia.org/wiki/Solar_tracker
Skip dow to the section of "Direct power lost (%) due to misalignment (angle i )" for how it effects the PV solar arrays....
http://www.starhop.com/library/pdf/stud … Int-19.pdf
Planet Mean Distance from Sun (AU) Relative Solar Intensity
Earth 1.000 1.000
Mars 1.524 0.431
Since the inverse square law for light is in play for the same source as the solar wind I would then say that the wind is effected by distance in the same manner....
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Yes, their atmospheres are reported to be similar.
Their magnetic fields are not. Venus by what I have read, has a weak magnetic field, but it does not reach appreciably up much beyond the surface. So, perhaps it is not of significance where the atmosphere and solar wind meet. Venus does apparently have a tail, but if I am to understand correctly even though the solar flux for Venus is ~4x that of Mars, Mars has a greater atmospheric loss problem.
It seems to be indicated that the lumpy fossil magnetic fields of Mars make the atmospheric losses greater. They apparently reach the interface between the atmosphere and the solar wind on Mars.
So about magnetic fields on Mars, as I see it you have some options.
1) Restart the existing mechanism of a magnetic field for Mars (I have no idea how, and I suspect it is exhausted, can't restart it).
2) Create an induced magnetic field (That's going to be a big cost, don't you have any other options, or why not just live with it.
3) Harvest the lost gasses if you can. Since the fossil field helps the solar wind strip off bubbles of plasma from the atmosphere, can you pick it's pockets and take that gas? (What would you use it for in orbit?)
4) Hammer the fossil magnetic fields into submission. Well, nuclear bombs? Asteroid strikes? (Disruptive, expensive, can you actually do it?)
5) Expand the height of the atmosphere so that the interface between the atmosphere and the solar wind is above the fossil magnetic fields.
(Don't know if you can do that. How much atmosphere can you create? How high do the fossil fields reach?).
So, you guys have any other notions on it?
I think just now #5 is the best option to investigate. If successful, it would not close the leak entirely, but it would valve it down a bit. Hopefully quite a bit.
Otherwise, if you can find a way to do jujitsu on the Solar wind and trick it into protecting the atmosphere of Mars, perhaps by generating a counter EMF, and a counter magnetic field, that would be what I would think to try. That would be a #2 method.
In my opinion on the basis of what I have read, we have chances of moving the Mars situation to more closely resemble that of Venus.
http://www-ssc.igpp.ucla.edu/personnel/ … /mars_mag/
Solar Wind Interaction
To date, the observations at Mars suggest that it great deal o similarity exists between near-Venus space and near-Mars space. Mars, like most of the other planetary obstacles, is preceded in the solar wind by a 'bow shock'-like structure that reflects the slightly greater than planet-size scale of the weakly magnetized Martian obstacle. The subsolar distance of the bow shock is ~ 1.5 Rm while its terminator position is ~ 2.7 Rm. Within the bow shock, the solar wind plasma is diverted around the obstacle. Within it, the imbedded interplanetary magnetic field is compressed against the obstacle nose. The field distortion associated with the divergence of the flow gives the 'draped' configuration of field lines illustrated in Figure 1.. This 'magnetosheath' is a common feature of all planetary obstacles.
Fig. 1. Illustration of the disturbance in the solar wind flow (a) and interplanetary magnetic field (b) produced by a planetary obstacle in the solar wind. Early spacecraft to Mars detected this disturbance, the size of which gave an upper limit to the strength of the Martian magnetic field. (J. G. Luhmann and L. H. Brace, Rev. Geophys., 29, 121, 1991, copyright American Geophysical Union).
Within the dayside obstacle boundary implied by the Mars bow shock position, the magnetic field geometry is unknown. However, both in situ measurements on the Viking Landers and radio occultation experiments on the Viking Orbiters and other spacecraft indicated the presence of a substantial dayside ionosphere below about 300 km. (The subsolar obstacle height inferred from the bow shock position is ~ 400 km.) The in situ measurements from the Viking Landers also provided information on the temperatures in the ionospheric plasma which were used to calculate the ionosphere's thermal pressure. This calculation resulted in the conclusion that Mars must have a planetary magnetic field of significance because these pressures were less than the incident solar wind pressure. Nevertheless, we know from the observations at Venus during disturbed solar wind conditions that an ionospheric obstacle can persist in the face of such levels of excess solar wind pressure. One possibility is that the Mars ionosphere, like that of the disturbed Venus counterpart, contains large-scale horizontal magnetic fields that are induced by the solar wind interaction. Models of these induced fields suggest that they should be several tens of nanotesla in strength. The electron temperatures measured in the ionosphere by the Viking Landers are also consistent with fields of this strength and orientation, but it is not clear from these whether the field is planetary or induced by the solar wind interaction.
As mentioned above, the Phobos 2 magnetic measurements in the near- equatorial wake of Mars showed that the fields in that region are controlled by the interplanetary field orientation. The relationship between the interplanetary field draped over the obstacle and the field in such an 'induced' magnetotail is illustrated by Figure 2. In spite of this finding, there are still advocates of an intrinsic field contribution to the Martian magnetotail because the magnetotail appears to be wider than that of Venus relative to the planet radius (~ 2.0 planetary radii in diameter compared to Venus' ~ 1.2). It is argued that this contribution has not been detected because the 'intrinsic' field tail features may be restricted to regions removed from the equator.
Fig. 2. Illustration of the 'induced' magnetotail in the wake of Mars and its connection to the draped interplanetary magnetic field (J. G. Luhmann and L. H. Brace, Rev. Geophys., 29, 121, 1991, copyright American Geophysical Union).
Phobos 2 did detect significant fluxes of planetary ions (mainly O+, as at Venus) that had been scavenged from Mars by the passing solar wind (e.g. see the Nature special issue mentioned above). The details of the acceleration of these ions are not completely understood, but the electric field in the solar wind is expected to remove ions formed in the upper atmosphere that extends above the 'obstacle' boundary into the magnetosheath and undisturbed solar wind. The observed rates of escape for the oxygen suggest that the solar wind scavenging process has the potential to remove all of Mars' present inventory of atmospheric oxygen over the next 108 years. These observations also suggest that the solar wind interaction must have played some role in the Martian atmosphere's evolution over the past 4.5 billion years, or at least after the thermally driven planetary dynamo ceased to operate.
Well, I see that I am on the wrong thread, but if you look at #5 as a solution then both threads have validity. I will copy this to the Magnetic field thread, and you may do as you wish Spacenut.
Last edited by Void (2015-11-17 14:29:38)
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This is a feedback theory of the atmosphere which could be a simplified model of the actual truth:
In relation to the history of Mars, perhaps a hydrocarbon childhood atmosphere, then moving to an Oxidizing atmosphere (Which might also promote acid PH?), the finally a CO2 dominated atmosphere where, Oxygen from CO2 lost to space is replaced by Oxygen from H20, as water evaporates into the atmosphere.
More CO apparently promotes more Ozone, and Ozone is some type of a greenhouse gas.
More water into the atmosphere, more O2 to the atmosphere when Hydrogen leaves it behind by being swept away by the solar wind. More O2, less CO, less CO less Ozone, less heat, less evaporation.
Simplified, but possibly why the pressure is hanging around 5-7 mb.
Just guessing.
On another thread magnetic fields are being discussed for Mars. Involved are the residual partial fossil magnetic fields, and the proposed, artificial augmentation of the existing field.
Also I have mentioned atmospheric height, relative to the heights of the fossil magnetic fields.
It is mentioned that the upper atmospheres of Venus and Mars appear to be similar, more similar to each other than to that of Earth.
However, it appears that Venus does a better job of resisting the solar winds, bad intentions of stripping it's atmosphere away.
So maybe we could say that if Mars was conscious, it might have a Venus envy.
So I will mention the relative advantages of Venus and Mars.
Temperature of upper atmosphere: Advantage to Mars? (I think)
Magnetic field : Advantage to Venus (The partial magnetic field of Mars is worse than not having on that reaches to the shock wave the solar wind creates upon impacting an atmosphere). Further, another way to describe it is that the atmosphere of Venus reaches so high above the magnetic field of Venus, that the magnetic field of Venus does not help to cause Venus to loose atmosphere.
Gravitational field : Advantage to Venus
Intensity of solar wind : Advantage to Mars
So, the two factors that might be modulated by humans most easily are;
1) The completeness and magnitude of the magnetic field of Mars.
2) The relative value of height between the magnetic field and the atmosphere of Mars. If the magnetic field completely and continuously envelopes the atmosphere, then the situation would be similar to Earth. If on the other hand the atmosphere completely enveloped to magnetic field, then it would be like Venus.
Of the three planets, Venus, Earth, and Mars, Mars has the greatest atmospheric loss problem. This is not likely to be because of atmospheric temperatures, since Venus and Earth are both hotter. It can involve gravity, but there is not much that we can do about the gravitation of Mars.
So, in my mind the objective is to prevent the solar wind, the upper atmosphere, and the partial magnetic fields of Mars from interacting as they do now, where the loss of atmosphere is amplified.
Choices:
1) Reduce the residual magnetic fields somehow so they don't stick up so far.
2) Add a artificial supplemental field to the existing partial field, of a magnitude to reduce direct contact of the solar wind with the upper atmosphere of Mars.
3) Increase the mass of the atmosphere of Mars, until it is high enough to prevent the solar wind and magnetic fields of Mars from connecting inside the upper atmosphere of Mars.
I don't know how high the fossil field reach, so I don't what would be required to achieve #3.
If #2 is implemented, it is likely to be at a cost. Technically since it is artificial, and likely to fall out of existence without intentional continuation, it can be use as a tool.
Tool A:
You can use greenhouse gasses to warm Mars, and therefore add greater humidity to the atmosphere of Mars. This should lead to more O2 and H2, where typically the H2 is more likely to be swept away by the solar wind.
Tool B:
You can artificially hydrate the atmosphere of Mars by shooting ice into it's atmosphere, or vaporizing water into it from a solar power tower. So this should do similar to tool A.
Tool C: Tools A & B.
These can increase the atmospheric density, perhaps moving the atmosphere high enough to shield the remnant magnetic field from the solar wind. Technically this could reduce the rate of loss of atmosphere.
Tool D:
Add Magnetic force to the field artificially. This can be a throttle. You could influence the rate of loss of H2 or O2.
Tool E: Somehow add extra CO to the upper atmosphere of Mars, to hope to facilitate the production and protection of Ozone.
That's what I have so far on the topic.
Enjoy, or hate as you might wish.
Last edited by Void (2015-11-18 16:39:30)
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Maybe the smoking gun has been staring us in the face all along with the Mars atmosphere only having Co2 remaining.
Planets with too much carbon dioxide could lose oceans to space
As the sun ages, it will get about 9 per cent brighter every billion years. The increase in solar radiation will warm the Earth, making water vapour mix into the upper atmosphere. There, water molecules will be exposed to ultraviolet rays, which will break them into hydrogen and oxygen – and then many of those lightweight hydrogen atoms will fly off into space. Over time, Earth’s oceans will dwindle, because the lost water is never replaced.
So add to that a lessoning magnetic field with solar winds and we have mars at its current state....
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I never thought Mars would be easy to terraform. I don't think everything is just waiting on the planet's surface to just throw some dirt on top of the ice caps, and then everything sublimes, thickening the atmosphere, and a global warming chain reaction causes more gases to be released from the rocks, melting permafrost to fill the ancient ocean basin in the Northern hemisphere, and soon enough we have a Mars with a thick atmosphere and balmy temperatures, ready for colonization with nothing but a gas mask in 50 years! Did you ever believe that? I didn't.
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An Earth analogue environment would not appear to be realistically achievable. But terraforming is about making the environment more habitable, not neccesarily completely analogue to Earth. From discussions on this board and the references cited, an atmospheric pressure of 30mb would appear to be achievable through sublimation of the polar cap and dry ice in the regolith. This might happen as a natural result of human colonisation, a colonised Mars would probably put nuclear power plants at the poles and use dry ice as a heat sink. There are fewer natural obstacles preventing power transmission than would be faced by a similar effort on Earth. That will naturally push up atmospheric pressure. Waste heat itself will increase average atmospheric temperatures.
30mb is sufficient pressure to allow water to liquefy at low temperatures. A limited ecosystem is therefore achievable without importing volatiles from the outer solar system. As water fills the northern and Hellas basins, aquatic ecosystems will begin to develop and algae will begin the process of converting atmospheric CO2 into oxygen. As oxygen levels rise on land, hardy plants will begin to propagate at low latitudes and will form the basis of a food chain.
From a human perspective, the greatest impediment to habitability is the need to grow food. If Mars can be terraformed enough to achieve that without pressure domes (maybe just poly-tunnels to protect crops from night-time cold), then survival becomes dramatically easier. That goal would appear to be achievable.
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