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Data released from the MAVEN probe suggests that most of Mars' atmosphere was lost to space in the first billion years of its history.
http://www.space.com/31031-mars-atmosph … maven.html
This would appear to put some tough limits on the realistic extent of future terraforming on the planet. Whilst large parts of the planet could eventually be para-terraformed, there would appear to be only a fraction of the gas necessary to produce an Earth analogue atmosphere without para-terraforming. Even a modest increase (doubling) of the atmospheric pressure would do a lot to reduce surface radiation levels. But it would appear unlikely that there will ever be a breathable atmosphere without domes.
From my point of view this may not matter too much. Humans tend to live in buildings and spend most of their time there. The absence of a breathable atmosphere and cosmic ray shielding outside is undesirable, but hardly a show stopper for mass-colonisation. Food can be grown in pressurised greenhouses or in ponds using algae-culture. Efforts can now focus on adapting human civilisation to the Martian environment as it is, given that terraforming is unlikely to be a practical goal.
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We know this. We didn't have data, but Pioneer Venus measured hydrogen flow off the back of Venus so it was reasonable to assume the same happened on Mars. The question is how fast. If it takes 100s of thousands of years to lose atmosphere, then terraforming is still reasonable. We've had long discussions on creating an artificial magnetic field to contain atmosphere. And we don't have to do it first, we can terraform first, create the magnetic field later, as long as erosion to space is slow.
How much is left? One team used telescopes on Earth to measure the ratio of hydrogen to deuterium in Mars atmosphere. Based on that ratio, and assuming Mars started with the same ratio as Earth, they calculated how much water was lost. They estimate very little water is left. However, that assumes their measurement is representative of all water on Mars. It isn't, that's their error. Ice is not involved in the hydrologic cycle on Mars. They only measured water in the upper atmosphere. In fact, ice measured by the ground penetrating radar MARSIS on Mars Express is already more than that.
The text book "Terraforming: Engineering Planetary Environments" cites two papers that estimate how much dry ice is on Mars. One estimates that if all dry ice were sublimated, it would produce a surface pressure of 200 mbar, the other estimates 300 mbar. Currently Mars has roughly 7 mbar. The bottom of Hellis Basic can get 9 mbar, and the top of Olympus Mons 1 mbar, but most of the surface of Mars is somewhere around 7 mbar. The winter pole is covered in dry ice; it sublimates each spring, and forms on the opposite pole as that pole enters winter. There is believed to be dry ice adsorbed into the soil. And MARSIS found a large deposit of dry ice deep within the water ice of the south pole. I haven't read a recent estimate of the CO2 budget, but all this sounds like the old estimates are accurate.
So not everything escaped into space. Much of the water is still there, just frozen. Much of the CO2 atmosphere is still there, just frozen as dry ice. There's enough water to completely cover the bottom of the ancient dried-up ocean basin in the northern hemisphere. Not to the same depth, but the same size. And there's enough dry ice to produce air pressure sufficient for a human to talk on the surface of Mars without a spacesuit. Just 30% the pressure of Earth, but enough. And it would be a CO2 atmosphere, so you would need an oxygen mask. But that's a lot better than a spacesuit.
New data from the report you linked
The Red Planet is currently losing about 100 grams of its atmosphere to space every second (a new result obtained via MAVEN observations), but the CME temporarily jacked up that rate by a factor of 10 or 20, Jakosky said.
We now have numbers. Can we estimate how long a terraformed Mars will hold onto it's atmosphere? Is it hundreds of thousands of years?
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Life on Mars without domes will not be a problem for people for quite some time to come anyway.
I recall that from the polar ice caps, the south cap in particular, Verified CO2 should be enough to raise the average from 5.5 to 11 mb.
This is supposed to be enough for snow, and with snow, can exist temporary melt streams.
The soil contains more if I am to believe the experts, so perhaps even though not enough for a non-pressure suit situation, enough for more permanent streams, and perhaps temporary ponds and lakes.
But I will deviate from that conversation and ask you to consider reading these references:
Deep layers of water ice and sediments over the entire northern hemisphere:
http://science.nasa.gov/science-news/sc … marswater/
Hypersaline Lake Nitrous Oxide Production:
Without Life:
http://www.nature.com/ngeo/journal/v3/n … eo847.html
In the presence of life at very cold temperatures:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3528574/
Nitrous Oxide Clathrates:
https://www.novapublishers.com/catalog/ … ad3598a587
So the first reference suggests that a "Third" reservoir of water is present.
The second and third reference suggest that Nitrous Oxide is formed in the presence of brine wetted soil.
The fourth reference suggests that Nitrous Oxide Clathrate could be present.
If this optimistic situation is true, then when the atmosphere of Mars began to thin and cool, the water pooled as ice in the northern hemisphere. Very deep ice. Very Very Deep. With soil sediments being mixed in.
This process would not have been overnight. So there would have been cold hypersaline lakes and seas, and still some snowfall, and daily or seasonal melts during transition. This would have transported some of the atmospheric gasses into the reservoirs below. There, perhaps action with the soil would have generated Nitrous Oxide, and cold and pressure may have preserved some of it as Clathrate.
I hate going out on a limb like this, but it appears that there are three reservoirs.
The first is the original common one, and then there was a split, where a large bulk (I hope) became buried underground, and the remainder gradually drained into space, leaving a residual atmosphere.
So the truth lies somewhere between this optimistic scenario and the scenario which was stated on the evidence of Mavin.
I am pulling for the 2 mile deep sediments of ice and soil in the Northern hemisphere, and by the way I have seen articles that indicate that it is present in the rift valley as well as part of that situation.
Imagine a system of above and below ground cities connected by buried hyperloops.
Never-the-less, although I am pulling for Mars to be a great place to set up shop, I like the Moon for reasons like this Mavin information.
Last edited by Void (2015-11-05 17:38:01)
I am starting to ask seriously "Why do I do this?"
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Even basalt has loads of oxygen locked up in it. Isn't it simply a question of melting the rocks to release oxygen or have I got that wrong? We could use either nuclear reactors or solar power (maybe from orbital satellites) to provide the energy for release of such gases.
Life on Mars without domes will not be a problem for people for quite some time to come anyway.
I recall that from the polar ice caps, the south cap in particular, Verified CO2 should be enough to raise the average from 5.5 to 11 mb.
This is supposed to be enough for snow, and with snow, can exist temporary melt streams.The soil contains more if I am to believe the experts, so perhaps even though not enough for a non-pressure suit situation, enough for more permanent streams, and perhaps temporary ponds and lakes.
But I will deviate from that conversation and ask you to consider reading these references:
Deep layers of water ice and sediments over the entire northern hemisphere:
http://science.nasa.gov/science-news/sc … marswater/Hypersaline Lake Nitrous Oxide Production:
Without Life:
http://www.nature.com/ngeo/journal/v3/n … eo847.html
In the presence of life at very cold temperatures:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3528574/
Nitrous Oxide Clathrates:
https://www.novapublishers.com/catalog/ … ad3598a587So the first reference suggests that a "Third" reservoir of water is present.
The second and third reference suggest that Nitrous Oxide is formed in the presence of brine wetted soil.
The fourth reference suggests that Nitrous Oxide Clathrate could be present.If this optimistic situation is true, then when the atmosphere of Mars began to thin and cool, the water pooled as ice in the northern hemisphere. Very deep ice. Very Very Deep. With soil sediments being mixed in.
This process would not have been overnight. So there would have been cold hypersaline lakes and seas, and still some snowfall, and daily or seasonal melts during transition. This would have transported some of the atmospheric gasses into the reservoirs below. There, perhaps action with the soil would have generated Nitrous Oxide, and cold and pressure may have preserved some of it as Clathrate.
I hate going out on a limb like this, but it appears that there are three reservoirs.
The first is the original common one, and then there was a split, where a large bulk (I hope) became buried underground, and the remainder gradually drained into space, leaving a residual atmosphere.
So the truth lies somewhere between this optimistic scenario and the scenario which was stated on the evidence of Mavin.
I am pulling for the 2 mile deep sediments of ice and soil in the Northern hemisphere, and by the way I have seen articles that indicate that it is present in the rift valley as well as part of that situation.
Imagine a system of above and below ground cities connected by buried hyperloops.
Never-the-less, although I am pulling for Mars to be a great place to set up shop, I like the Moon for reasons like this Mavin information.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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This is why I want to have a full spectrum interest. (It was here anyway). Moon, Asteroids, Mars.
The news business makes money off of news. This means they have to skew the news in a manic depressive way to get the most they can.
Just now they are going to run with this in the direction of depressive.
You have to expect this, and put a saddle on it, and ride it.
And your strategy for Mars has to be generalized enough to survive it.
I think the Antarctic Scientific mission model you people have provided is a logical candidate for a method which could endure such negative news. Once you have boots on the ground, and more information and new ideas, then a pathway to terraforming of some type will emerge.
I am starting to ask seriously "Why do I do this?"
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I ran the numbers. The martian atmosphere has a total mass of 2.66E16 kg (26.8 million million tonnes). Based upon an average loss rate of 0.1kg/s, the half-life of the Martian atmosphere would appear to be 5.8billion years. Loss rate may have been much higher in the past, partly due to the increased activity of the nascent sun, but also due to the greater physical extent of the atmosphere, which would have reduced escape velocity in its upper layers. The loss rate would probably not be disproportionately greater for nitrogen for two reasons: (1) Most of the escape is in the form of exosphere ions, such as CO and O, and nitrogen is not disproportionately lighter on this basis; (2) the strong triple covalent bond in N2 means that it is less easy to ionise than CO2.
I can foresee a plausible mechanism for long term sequestration of CO2 as a solid on Mars. Due to the absence of a large stabilising moon, the planet is liable to extreme variations in its axial tilt. If this were to occur, the darkened hemisphere of the planet would face a huge drop in insolation with the polar region in perpetual darkness. Temperatures would drop to -120C at which point the polar cap would grow due to CO2 condensation. In the past, the cap may have achieved a thickness many miles before the tilt stabilised. Intermixed with the ice would have been dust spread by wind.
Mars has a relatively weak geothermal heat source, though it is very likely to have been stronger in the past. Earth’s average geothermal leakage is 0.087W/m2. Even at these tiny power levels, a layer of solid CO2 ice hundreds of metres thick would have provided enough insulation for temperatures at its base to reach the CO2 liquidus line (follow link to CO2 phase diagram).
http://www.powerengineeringint.com/arti … hemes.html
At this point, liquid CO2 would have soaked through fissures in the bed rock beneath the cap. It is interesting to note from the phase diagram that at pressures above 70 bar (700 metres beneath the Martian surface) CO2 cannot enter the gas phase at any temperature – it exists as either a liquid or solid up to a temperature of 304K, beyond which it transitions to a super-critical fluid. This fluid has very low viscosity. As the Martian crust continued to cool, it would have permeated deeper and deeper.
When the tilt corrected itself and the cap retreated, liquid CO2 that had permeated the deep bedrock would remain there as liquid, as the weight of the overlying rock would prevent phase transition into gas. CO2 trapped in the upper bedrock would freeze, as geothermal heat dissipated.
The deep liquid and supercritical CO2 may have migrated far from the polar regions. It is entirely possible that huge reservoirs of super-critical CO2 remain trapped in cavities deep underground.
It may have taken only a few axial ice-ages to considerably drain the Martian atmosphere in this way. As these occur on a timescale of a few hundred millennia, it is reasonable to assume that they were at least as significant in draining the atmosphere as solar wind events. To this day, much of the planet’s atmosphere may remain trapped as a super-critical fluid deep within its interior. Increasing temperatures using greenhouse gases would allow retrieval of the frozen portions in the upper bedrock. The remainder would require a lot of drilling.
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I like that information.
I would like to try to support it from another direction.
It has for a very long time bothered me that the average surface pressure of Mars is very near the triple point of water.
Given enough time after the proposed atmospheric collapse, the atmosphere should oscillate around a new stable situation.
Currently without knowing more, I would speculate that it oscillates around the triple point of water. I really am not sure why.
There are two possibilities that I can think of.
1) There is no such reservoir like what you suggest, and the air has been leaking at some linear or logarithmic rate over time since the magnetic field stopped protecting the planet, and we just happened to send probes to the planet, just at the point in time where the remnant atmospheric pressure was at the triple point of water. If this were true and remained true forward in time it should only be a relatively short period of time before Mars is as airless as the Moon (Unless there is some volcanism still).
2) There is a subsurface reservoir which keeps the atmosphere replenished at the triple point of water, and the pressure of Mars has been oscillating around that pressure for billions of years. Possibly an impact event has temporarily modified the situation and bumped the atmospheric pressure up, but for the most part the pressure has been around 6 mb on average for quite some time.
I think that #1 is unlikely. The chances are small.
I had considered it possible that the polar ice caps and buried ice have kept the atmosphere inflated. However they supposedly move about from poles to Equator over time. Maybe?
I think it is more likely that a slab of ice half the size of the planet several miles/kilometers thick, composed of water ice, CO2, and Clathrates of Nitrogen and CO2 would be able to keep that regulation going.
Perhaps I should get off your side before I stink your work up. I am still not satisfied I understand how #2 could work, but I really think #1 is improbable.
As for CO2 reservoirs, I recall that one of the Radar mappers found a flat surface under ice, that resembled an underground lake under ice.
But the temperatures were too cold. I think you might want to think Carbonated water, or even liquid CO2. Perhaps it might be.
Last edited by Void (2015-11-06 14:29:25)
I am starting to ask seriously "Why do I do this?"
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Isn't this argument rather redundant in terms of terraformation? It's not as though the residual atmosphere is going to slip away in the next 100 years and we will certainly begin terraformation within 100 years.
Within 200 years we could be pumping out billions of tonnes of gas per annum through a variety of means.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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Pumping out gas requires an economically super life support system. Advanced from what we have on Earth. Understanding what the nature of Mars is will allow us to understand what it wants to provide us, and what will make it angry.
I know that sounds silly, but in my opinion, a standard terraform plan (Expand CO2 volume) will endanger the usefulness of vast portions of the planet for use, for a very long time, if indeed a portion of a collapsed atmosphere is contained in basins such as the Northern Hemisphere.
Melting a thick layer of ice will be very unstable, particularly if there are dust sediments layered in it.
For instance you might have a lake develop on the surface, and yet one day a quake opens a crack, and the water gushes down and ice heaves up.
I also question the relative value of a cool Mars with an expanded 6-(300-1000) mb atmosphere of CO2, to an alternative which would be a cold Mars with an expanded atmosphere of ~11 mb converted to O2 with room to gradually bring that up to a hoped minimum 250 mb 02.
My opinion at this time is to primarily make solar thermal towers with heliostats. Those towers, not directly boiling water, but rather holding a micro-organism such as spirulina, and generating O2 both from CO2 and H20. And creating biomass.
https://en.wikipedia.org/wiki/Spirulina … upplement)
But this is my view.
I think that having a atmosphere of lets say 250 mb O2 with an Ozone layer will be more valuable than having one of 250 mb of CO2 without an Ozone layer. (Keep in mind that ~125 mb of that O2 might come from H2O).
I think that having a atmosphere of lets say 50 mb O2 with an Ozone layer may be more valuable than having one of 250 mb of CO2 without an Ozone layer. (Keep in mind that ~25 mb of that O2 might come from H2O).
If it is true that the Northern Hemisphere is largely filled with very deep sediments of Water Ice, Volcanic ash, wind blown dust/sand, CO2 layers buried, and perhaps Nitrous Oxide Clithrates, then a world within a world can be created.
A "Downstairs" world which would consist of partially buried cities with solar towers where Spirulina (Or other things) could be grown in concentrated light. The solar towers can also be a source of electrical power without damaging the biological function.
These partially buried cities, towns and houses can be connected by tunnels, some of which would be hyperloops.
Although people might venture on the surface in spacesuits, I anticipate that they will be able to do most surface work with virtual reality/telepresence methods.
When they go to the surface in a suit or a car, they might be much more benefited by having a 250 mb of O2 than with 250 mb of CO2.
When they got on the surface, many places might usually be too cold for active life on the surface, but Lichens, and Cyanobacteria and Algae would be possible most places, and in many places there would be times daily or seasonally where temperatures could approach or exceed the freezing point of water. Keep in mind that Lichen can grow even if it gets watered by snow, it does not even have to go above freezing temperatures to grow.
For the Northern Hemisphere, it would be very important to make sure that the permafrost was not disrupted by excessive high temperatures. In building up an O2 dominated atmosphere, you would want to just leak a trickle of additional CO2 to the initial starting value of about 11 mb. (~11 mb if you vaporize what is know to exist in the south ice cap).
What about the Southern Hemisphere? Well it has ice layers as well towards the poles, so the plan sort of applies.
As for the deep basins, how about orbital mirrors to warm them up? Then you could have as warm a climate in those southern basins as you might want. The Sahara, if you want. But the Southern Ice Cap being at elevation you should also be able to melt it with mirrors and get rivers to run into those basins, such as Hellas, and with the additional drop in altitude, should have a higher air pressure in those basins.
Hopefully not too much a partial pressure of O2.
So far I am the only one who recommends this plan. But obviously if the nature of Mars is that it has a part of a collapsed atmosphere in it's Northern Hemisphere, we want to know.
That's how I think. That's how I do my process. I would not choose to do it any other way.
However, remember that I will be dead and gone, so don't get wild on me about it.
Last edited by Void (2015-11-06 20:23:23)
I am starting to ask seriously "Why do I do this?"
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An 11mb atmosphere would appear to be achievable even under the most pessimistic assumptions. Keep in mind that even if it were possible to produce a 250mb CO2 atmosphere, it could produce some very undesirable side effects.
At present, Martian dust storms aren't much of a threat to human settlements on Mars because the air is too thin to exert very much dynamic pressure. For the same reasons, wind loadings won't be a serious concern when building structures on Mars and the poor convection within the thin Martian atmosphere will help keep things warm. The enormous day-night temperature variations would complicate agriculture, but they can also be exploited as a useful source of power. The atmosphere as is can be used to provide all the air and fuel that we will ever need on Mars, but at the same time provides little atmospheric drag, allowing ballistic transport between any two points on the planet. My point is that present Martian conditions present some strong advantages to human colonists on the planet and terrforming would ruin them.
That being said, a modest increase in atmospheric pressure would be desirable. Below is a link to a surface radiation map of Mars.
http://www.jpl.nasa.gov/spaceimages/det … d=PIA03480
This is the dose that a completely unprotected human being would recieve on the surface if exposed for a whole solar year. On the Tharsis bulge, where atmospheric pressure is about 5mbar on average, the radiation dose approaches 200mSv per year. That's a lot, even if colonists only spend 10% of their time outside of the habitat. In Hellas, where pressure is closer to 11mbar, the unprotected radiation dose is closer to 100mSv per year. So every 6mb of additional pressure you can create, would reduce surface radiation dose by half. An 11mb global datum would be a lot easier for human colonists than a 7mb global datum.
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Very good stuff. Much of it I had not thought about.
I think in many ways our ways are not parallel exactly but they converge very closely where it matters.
I would think that if the intention was to put humans on Mars, then:
1) Backpacker visits, outposts.
2) Establish a full habitation at most favored locations.
*In my ideal, this would be small "Towns" near the equator, and the beginnings of Megga-Cities at locations of deep ice laden sediments.
-If the Northern Hemisphere is a deep basin partially filled with ice and other sediments from a collapsed Hydrosphere/Atmosphere, then a partially underground city started at a favorable location there. It is even possible that the start would be within the;
https://en.wikipedia.org/wiki/Valles_Marineris
Fossil Ice in Valles Marineris:
http://www.sciences.univ-nantes.fr/lpgn … 85&lang=en
http://www.dmzone.org/papers/Gourroncetal2014_VM.pdf
Interestingly this one had the NASA emblem on the page, but not when I paste it here:
http://adsabs.harvard.edu/abs/2014Geomo.204..235G
I really like this one:
https://planetarygeomorphology.wordpres … eris-mars/
And just observe the brilliance of this guy!
http://www.newmars.com/forums/viewtopic.php?id=7291
To me the rift valley information suggests that during the final phases of the transition, a troposphere still existed in the low basins, which would include the Northern Hemisphere, and the Valles Marineris, and that the areas above that were already approaching conditions similar to those on Mars today.
So, returning to habitation and terraformation, as I see it:
Once you start your mega-city in the fossil ice deposits somewhere, the atmosphere is primarily a raw materials resource. Carbon and Oxygen, primarily Carbon.
Of course as you have indicated it is also to a degree a radiation shield.
So, in order to make your underground mega-city with solar towers with heliostats, you will use a fair amount of materials incorporating Carbon and Hydrogen in their structures. You will generate hydrocarbon pollution to the atmosphere naturally. (Or unnaturally if you prefer to say it).
So, you will have a bias to begin ridding Mars of CO2 condensation, by warming, to bring the atmospheric pressure up to 11 mb CO2.
If desired, at first and if affordable they may also manufacture and release a small amount of super greenhouse gasses to start the process up sooner.
At that point I have read that in addition to not having your seasonal CO2 caps anymore, you would have real snowfalls, and snowmelts and temporary streams. For the southern hemisphere low latitudes this will be valuable as you could create a method to capture those snow melts and use the water locally perhaps in a mining operation for instance. Your minerals will be where they are, and if the Northern Hemisphere is covered with sediments, it means that many minerals will not be accessible there.
Back to the Mega-city:
Although other solar methods are not against the law , I focus on bio-solar towers with heliostats. Among the things to grow being spirulina, which is eatable, and will generate oodles of Oxygen, and will capture Carbon from compressed atmosphere, and Hydrogen from water to produce hydrocarbons which may be used to create city structure under the ice and in sandstone under the ice.
So, you harvest Carbon from the atmosphere, Hydrogen from water ice, release O2 to the atmosphere, build a very massive underground mega-city which might cover 1/2 of the planet. You import massive amounts of people from Earth (If you have massive advances in technology).
You end up with a 11 mb atmosphere of O2 with a pinch of Nitrogen, Argon, and Carbon Dioxide, and;
You get an Ozone layer (I hope) and;
You may grow Lichens, Cyanobacteria, Algae on the open surface.
Should the inhabitants elect to up the greenhouse effect and release more CO2 from the ground (Presumably available), or get it from asteroids, then the atmosphere could be brought up to higher levels of pressure. But that would be up to the inhabitants.
I will point out to others that 11 mb of O2 should leave Mars approximately as cold as 7 mb CO2, so if going to a O2 atmosphere, I think you would want to bring it up to 22 mb O2 minimum in order to sustain snowfalls, snow melts, and temporary streams.
22 mb O2 would do a little more perhaps to reduce the temperature swings day and night, and would also circulate heat from equator to poles a little more, but not that much.
Last edited by Void (2015-11-07 09:45:33)
I am starting to ask seriously "Why do I do this?"
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Data released from the MAVEN probe suggests that most of Mars' atmosphere was lost to space in the first billion years of its history.
http://www.space.com/31031-mars-atmosph … maven.html
This would appear to put some tough limits on the realistic extent of future terraforming on the planet. Whilst large parts of the planet could eventually be para-terraformed, there would appear to be only a fraction of the gas necessary to produce an Earth analogue atmosphere without para-terraforming. Even a modest increase (doubling) of the atmospheric pressure would do a lot to reduce surface radiation levels. But it would appear unlikely that there will ever be a breathable atmosphere without domes.
From my point of view this may not matter too much. Humans tend to live in buildings and spend most of their time there. The absence of a breathable atmosphere and cosmic ray shielding outside is undesirable, but hardly a show stopper for mass-colonisation. Food can be grown in pressurised greenhouses or in ponds using algae-culture. Efforts can now focus on adapting human civilisation to the Martian environment as it is, given that terraforming is unlikely to be a practical goal.
I shrug my shoulders at this, I expected to have to import atmosphere anyway. Mars is just inside the asteroid belt, the belt probably contains enough gases locked in its rocks to provide a 1 bar atmosphere on the surface of Mars, and if not there are the Jovian Moons, the ice in Callisto, the outermost Galilean Moon, has enough oxygen to make a breathable atmosphere on Mars. There are various nitrogen compounds that contain nitrogen.
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Very good stuff. Much of it I had not thought about.
I think in many ways our ways are not parallel exactly but they converge very closely where it matters.
I would think that if the intention was to put humans on Mars, then:
1) Backpacker visits, outposts.
2) Establish a full habitation at most favored locations.
*In my ideal, this would be small "Towns" near the equator, and the beginnings of Megga-Cities at locations of deep ice laden sediments.
-If the Northern Hemisphere is a deep basin partially filled with ice and other sediments from a collapsed Hydrosphere/Atmosphere, then a partially underground city started at a favorable location there. It is even possible that the start would be within the;https://en.wikipedia.org/wiki/Valles_Marineris
https://upload.wikimedia.org/wikipedia/ … oom_64.jpgFossil Ice in Valles Marineris:
http://www.sciences.univ-nantes.fr/lpgn … 85&lang=en
http://www.dmzone.org/papers/Gourroncetal2014_VM.pdf
Interestingly this one had the NASA emblem on the page, but not when I paste it here:
http://adsabs.harvard.edu/abs/2014Geomo.204..235G
I really like this one:
https://planetarygeomorphology.wordpres … eris-mars/
And just observe the brilliance of this guy!
http://www.newmars.com/forums/viewtopic.php?id=7291To me the rift valley information suggests that during the final phases of the transition, a troposphere still existed in the low basins, which would include the Northern Hemisphere, and the Valles Marineris, and that the areas above that were already approaching conditions similar to those on Mars today.
So, returning to habitation and terraformation, as I see it:
Once you start your mega-city in the fossil ice deposits somewhere, the atmosphere is primarily a raw materials resource. Carbon and Oxygen, primarily Carbon.Of course as you have indicated it is also to a degree a radiation shield.
So, in order to make your underground mega-city with solar towers with heliostats, you will use a fair amount of materials incorporating Carbon and Hydrogen in their structures. You will generate hydrocarbon pollution to the atmosphere naturally. (Or unnaturally if you prefer to say it).
So, you will have a bias to begin ridding Mars of CO2 condensation, by warming, to bring the atmospheric pressure up to 11 mb CO2.
If desired, at first and if affordable they may also manufacture and release a small amount of super greenhouse gasses to start the process up sooner.
At that point I have read that in addition to not having your seasonal CO2 caps anymore, you would have real snowfalls, and snowmelts and temporary streams. For the southern hemisphere low latitudes this will be valuable as you could create a method to capture those snow melts and use the water locally perhaps in a mining operation for instance. Your minerals will be where they are, and if the Northern Hemisphere is covered with sediments, it means that many minerals will not be accessible there.
Back to the Mega-city:
Although other solar methods are not against the law, I focus on bio-solar towers with heliostats. Among the things to grow being spirulina, which is eatable, and will generate oodles of Oxygen, and will capture Carbon from compressed atmosphere, and Hydrogen from water to produce hydrocarbons which may be used to create city structure under the ice and in sandstone under the ice.
So, you harvest Carbon from the atmosphere, Hydrogen from water ice, release O2 to the atmosphere, build a very massive underground mega-city which might cover 1/2 of the planet. You import massive amounts of people from Earth (If you have massive advances in technology).
You end up with a 11 mb atmosphere of O2 with a pinch of Nitrogen, Argon, and Carbon Dioxide, and;
You get an Ozone layer (I hope) and;
You may grow Lichens, Cyanobacteria, Algae on the open surface.
Should the inhabitants elect to up the greenhouse effect and release more CO2 from the ground (Presumably available), or get it from asteroids, then the atmosphere could be brought up to higher levels of pressure. But that would be up to the inhabitants.
I will point out to others that 11 mb of O2 should leave Mars approximately as cold as 7 mb CO2, so if going to a O2 atmosphere, I think you would want to bring it up to 22 mb O2 minimum in order to sustain snowfalls, snow melts, and temporary streams.
22 mb O2 would do a little more perhaps to reduce the temperature swings day and night, and would also circulate heat from equator to poles a little more, but not that much.
Sounds like a plan. I have always been of the opinion that by the time Mars was terraformed, the planet would already be substantially paraterraformed. Even with the present Martian atmosphere, there is more than enough gas to parraterraform the planet. This could be done using simple modular steel frames with glass pane windows, counter weighted against Martian rock.
A million cubic km of ice is a lot, enough to cover the whole planet to a depth of several metres if it were smooth.
Last edited by Antius (2015-11-07 11:44:04)
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Is there a way to calculate how much gavity would need to change by in order to stop the lose rate due to the solar winds and then from that amount of gravity change we could then solve for the amount of mass to make that happen. If that mass is centered around the equator to concentrate the effect.
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Is there a way to calculate how much gavity would need to change by in order to stop the lose rate due to the solar winds and then from that amount of gravity change we could then solve for the amount of mass to make that happen. If that mass is centered around the equator to concentrate the effect.
Lack of gravity isn't the problem. The catastrophic loss started when the planet lost its magnetic field. The (then) more extensive atmosphere was scoured by solar winds from the nascent sun. The present loss rate appears to be quite modest in comparison, but the damage is done.
This isn't to say that no terraforming could take place. There would appear to be substantial gas remaining. But we need to temper our expectations. A strictly Earth analogue environment is probably not achievable given the extent of past volatile losses. Transporting mass or volatiles from other solar system bodies would be a very expensive long term project and more than a little risky. In my opinion it just doesn't work economically. But who knows? In a thousand years immortal beings of infinite wealth might decide to make that very long term investment.
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I prefer that someone else will do the last post on this thread, but I feel like adding further encouragement.
In my view, Mavin by itself is fairly scary. However for my mind, evidences from articles, and calculations from Antius paint a picture of Mars that may be better than what was supposed.
A good reason to set some people up on Mars, is so that they can be in a place which is not a strong analog of Earth. It must however provide the real potential for substantial rewards for those willing to struggle. I believe that the Mars I think I am seeing is better for that than the one which was previously supposed.
I have always been a slow and incomplete learner, so I will review this:
https://en.wikipedia.org/wiki/Conflict_(narrative)
2.1 Man against man 2.2 Man against society 2.3 Man against nature 2.4 Man against self
Man against nature is the one where technologies are developed which can truly benefit humans.
I am afraid that on Earth we have too much of the other ones, particularly Man against man.
They will all follow humans to Mars, but Mars will give rewards to people of tools more then might otherwise be. Earth currently gives more and more rewards to people of words and weapons. This is the pathway to the death of consciousness.
The people who rule with books can both be demons or angels perhaps.
So, the typical pattern is for well damaged societies to obtain technology from tool inventing cultures, and use excessive language and communication skills to invent a story of how "Those other people" are bad for some reason. In it's worst form you will see them using advanced weapons, skills invented by others, violence, and a actual lack of true intelligence to conquest neighbors. Yes every nation does a bit of that, but some can only do that. And we have one that emerged that thinks it has a right to take other people as slaves, or to kill them for not submitting. Completely depriving them of free will.
This unfortunately is what happens when people stumble on to a vast bucket of wealth, without having to struggle technologically. They are idiot savants at cruelty, violence, and domination.
A good way to turn the human race at least partially away from this degeneracy, is a new frontier, and if it has rewards and requires technological struggle for reward, then it is good for the quality of future humans.
The Mars I am seeing now may very well have very large pockets of water ice at the equator, which in my mind makes the level of struggle needed to inhabit Mars proportioned appropriately. Social orders there will just not have that much room for slave masters. Sure they can go there and try to set up their Man over Man feeding frenzy, but as their slave, I might just forget how to maintain their life support. Oops!
Last edited by Void (2015-11-08 18:16:48)
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Gas is surely just a form of matter. The reality is there are many, many trillions of tonnes of matter in the regolith of Mars which can be converted into gas - just think of all the iron oxide, with oxygen bound in it. Talking about gas as gas on Mars is irrelevant. All you need to convert the solid matter into gas is energy - and that can come either through nuclear power or solar satellites.
SpaceNut wrote:Is there a way to calculate how much gavity would need to change by in order to stop the lose rate due to the solar winds and then from that amount of gravity change we could then solve for the amount of mass to make that happen. If that mass is centered around the equator to concentrate the effect.
Lack of gravity isn't the problem. The catastrophic loss started when the planet lost its magnetic field. The (then) more extensive atmosphere was scoured by solar winds from the nascent sun. The present loss rate appears to be quite modest in comparison, but the damage is done.
This isn't to say that no terraforming could take place. There would appear to be substantial gas remaining. But we need to temper our expectations. A strictly Earth analogue environment is probably not achievable given the extent of past volatile losses. Transporting mass or volatiles from other solar system bodies would be a very expensive long term project and more than a little risky. In my opinion it just doesn't work economically. But who knows? In a thousand years immortal beings of infinite wealth might decide to make that very long term investment.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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This topic ties in with Artificial Magnetosphere - Electromagnetic Induction
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I feel that it has to be remembered that the western notion of how to exist usually is a bit light on methods harmonization. China is centered on that concept I believe.
Humans, and really all life forms, are more like a sea lamprey when you drill down deep.
https://en.wikipedia.org/wiki/Sea_lamprey
There, that's what we really look like in the mirror.
Even Cyanobacteria/Algae, intercept the path of hapless photons, and chemicals, and feed off of them. And it all appears to be driven by entropy.
As in some true eastern (Not Middle Eastern) thinking, we are like a whirl pool.
https://en.wikipedia.org/wiki/Whirlpool
So, being truthful to ourselves we admit that we do feed off of the universe, like a baby on a parent:) Ha ha found a way to say it without the creepy police getting on the issue. It's the nicer view, we are children and the universe our parents, or perhaps we are just parasites.
Whatever you feel works for you.
So, if we propose to do anything the first thing to admit is that we feed off of entropy.
So, we have a choice in manipulations. We can manipulate in ways that do not harmonize with entropy and pay a greater cost, or we can admit that we are not generative, but rather a path for entropy, and so do our manipulations in greater harmony or cost effective harmony with entropy so as to earn a living, amplifying our investment from the forces of the universe.
At this time I consider an artificial enhancement of a magnetic field worth conversation, but likely to be non-harmonious with our abilities to extract wealth from the universe.
The Mars I now see, may be within the grasping capabilities of humans to harness it's potential entropy pathways, and that seems likely to be a profitable proposition, which is necessary if we would want to foster the continuation of our pattern types through at least the four dimensions commonly perceived by us.
Study of magnetics on Mars will be wise, but it will have to be some very unlikely trick of fate that we might find that we can simply flick a light switch and turn its magnetic field back on, and generation of an artificial one would be a horrendous cost.
Last edited by Void (2015-11-09 11:15:22)
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Yes, Louis, the regolith as well. Specifically the dunes perhaps.
Design solar powered robots that will eat the dunes, extract special materials such as metals if that is possible, create reduced materials such as metal parts, and ceramic blocks, ect, and expel Oxygen and perhaps other gasses.
Some of those parts, metal and ceramic, being used to build still other of the dune eating robots.
Nice, not quite https://en.wikipedia.org/wiki/Von_Neumann_machine
But I would think that perhaps humans and https://en.wikipedia.org/wiki/Telepresence
could be used to assemble those new machines. As the dunes got eaten, more atmosphere, more machines, more humans.
Why not?
Parts manufactured for the new machines, or repairs of such machines, and then might include parts to make stone towers, for future purposes such as wind towers. If the planet is going to be windy later, might as well take advantage of it. And of course parts for buildings and other machines, if that much materials are available.
I would presume if manufactured correctly it would take a long time for ceramic parts to become Oxidized again.
Louis wrote:
Gas is surely just a form of matter. The reality is there are many, many trillions of tonnes of matter in the regolith of Mars which can be converted into gas - just think of all the iron oxide, with oxygen bound in it. Talking about gas as gas on Mars is irrelevant. All you need to convert the solid matter into gas is energy - and that can come either through nuclear power or solar satellites.Antius wrote:
SpaceNut wrote:
Is there a way to calculate how much gavity would need to change by in order to stop the lose rate due to the solar winds and then from that amount of gravity change we could then solve for the amount of mass to make that happen. If that mass is centered around the equator to concentrate the effect.
Lack of gravity isn't the problem. The catastrophic loss started when the planet lost its magnetic field. The (then) more extensive atmosphere was scoured by solar winds from the nascent sun. The present loss rate appears to be quite modest in comparison, but the damage is done.
This isn't to say that no terraforming could take place. There would appear to be substantial gas remaining. But we need to temper our expectations. A strictly Earth analogue environment is probably not achievable given the extent of past volatile losses. Transporting mass or volatiles from other solar system bodies would be a very expensive long term project and more than a little risky. In my opinion it just doesn't work economically. But who knows? In a thousand years immortal beings of infinite wealth might decide to make that very long term investment.
Lack of gravity isn't the problem. The catastrophic loss started when the planet lost its magnetic field. The (then) more extensive atmosphere was scoured by solar winds from the nascent sun. The present loss rate appears to be quite modest in comparison, but the damage is done.
This isn't to say that no terraforming could take place. There would appear to be substantial gas remaining. But we need to temper our expectations. A strictly Earth analogue environment is probably not achievable given the extent of past volatile losses. Transporting mass or volatiles from other solar system bodies would be a very expensive long term project and more than a little risky. In my opinion it just doesn't work economically. But who knows? In a thousand years immortal beings of infinite wealth might decide to make that very long term investment.
Last edited by Void (2015-11-09 15:26:41)
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I proposed a slow inflation of the Mars atmosphere, where we might hope to convert it to O2, so as to maintain an Ozone layer early on.
For me this makes more sense than a fast inflation of a atmosphere which would potentially reduce the need for pressure suits, but would involve maintaining a CO2 dominated atmosphere.
My concerns were the melting of permafrost under the fast inflation model, and Antius brought up the dust storm problem, and also if I recall correctly indicated that their would be a wind load problem from a thicker atmosphere, due to the day/night extremes of temperature, even at say 250 to 300 mb of atmosphere.
I choose to list some further thoughts on this.
First of all a potential problem with the slow inflation O2 dominated model. As in the biosphere experiments, it may prove true that O2 will react with the surface materials of Mars. This could be detrimental, or beneficial.
Detrimental: You loose your Oxygen to from the atmosphere, and it gets locked up in the soil.
Beneficial: It is possible, that if indeed a great deal of the dust has come from off of Mars, perhaps at greater depths, a great deal of Carbonaceous material has been deposited.
https://en.wikipedia.org/wiki/Carbonaceous_chondrite
This will of course tend to absorb Oxygen, but it might also release Carbon Monoxide, Carbon Dioxide, and H20 to the atmosphere over time. So, perhaps by this method more atmospheric materials made available which would not become available if you simply did a quick inflation on CO2.
It might be interesting in fact to verify if such materials are significantly present how much Methane might be generated by warming the surface, and providing Oxygen to potential organisms which might feed off of the Carbonaceous. This is important because it might skew your warming schedule, but it might also reduce the amount of greenhouse gasses which would be required to be generated mechanically by humans and their machines.
Under the slow inflation model of O2, the dust hazard would mount up more slowly of course. So, due to the time delay, the costs can be delayed, and perhaps using special tricks reduced substantially.
One method is to feed off of the dust/sand dunes. Design robotic automation which will eat them and manufacture useful materials. Extract metals, if any, glass, if possible, and make bricks/tiles and so on. This I presume would be powered by the sun.
Another method should an Ozone layer actually be accomplished, might be to use vascular plants to hold the dunes down. I would expect this to be most possible at the poles, where more moisture might be available seasonally (Summer), and where the midnight sun would provide a minimum of say 60 frost free days each year. We would be talking about dunes covered in tundra/or steppes or some analog of them.
https://en.wikipedia.org/wiki/Steppe
If you could somehow engineer trees which might survive the hideous winters, then maybe Taiga.
https://en.wikipedia.org/wiki/Taiga
Under the slow inflation O2 method, you might contemplate forced melting of the southern ice cap to produce rivers early on. Ice covered rivers would flow even maybe under 22 mb of pressure, or perhaps even less. Allowing that water to flow down to basins such as Hellas, you might harness the hydro-electric power, and fill a small sea.
Terraformer has been contemplating a ecosystem which might generate it's own suntan lotion, so perhaps this could be done even if you don't have a good Ozone layer. But anyway presuming a pressure of 22 mb at the lowest points of the the south ice body, I would suppose maybe 44 mb at the the bottom of Hellas at that time. Perhaps possible if salt added to have patches of open water which would catch dust. And of course such a sea would become a resource, and perhaps a significant help in converting more CO2 to O2 and Hydrocarbon materials.
As for wind loads, above ground building would simply have to be made to cope with it as the pressure moved higher.
I have also tried to imagine a hybrid situation where a pool of CO2 atmosphere was below a upper atmosphere of O2, so as to be able to have an Ozone layer, and also use more CO2 to inflate the atmosphere, but I am betting that atmospheric mixing will be too intense for such a stratification to be possible.
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SOLAR SINTER:
http://techcrunch.com/2014/09/25/3d-pri … f-the-sun/
“So what are you doing this weekend, Markus?”
“Oh, you know. Heading out to the desert and harnessing the power of the sun to make a 3D printer that can print objects out of sand. You?”
“… catching up on Breaking Bad.”
You know the kid in your old neighborhood that spent his spare time frying ants with a magnifying glass? This is like that — except instead of a magnifying glass, he’s using an big ol’ fresnel lens. And instead of roasting insects, he’s melting freaking sand into stuff.
Built by artist Markus Kayser, the “SolarSinter” concept isn’t too disimmilar from laser sintering printers used by operations like SpaceX to print otherwise impossible objects out of metal. A focused sun beam is a whole lot less precise than a finely-honed laser, of course — but the core concepts are the same.
I bet this guy could make a mean sand castle.
So, I think it is cool. Of course on Mars, the sand would be dominantly basalt, so a bit different.
However I have to ask the question "What if I were to spray a stream of CO or H2 on to the melt spot? It should pluck Oxygen and perhaps some other molecules from the melt, and I guess what you did with the result would be up to you. But you would have an object that is more reduced of O2, and you would have a source of O2.
Perhaps if harvest of metals would be possible you would do that as well. That could be done magnetically, or in the melt, I think possibly with electrolysis?
Way on in the future on Mars, solar dune eating machines!
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http://www.compositesworld.com/articles … e-to-glass
http://smalltridesign.com/Trimaran-Arti … fiber.html
Agreed a slow atmospheric build up with a shield put in place to slow the winds would be a must from what Maven has given us for data.....
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That's very hopeful, when you see that humble rocks might be upgraded to a much greater value to humans.
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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.
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