How could we make an atmosphere in Mars?

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Offline lungo

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How could we make an atmosphere in Mars?
« on: 05/07/2015 08:13:18 »
Dear forum,

I am a screenwriter currently working on a story that takes place in Mars several hundred years after the start of an extensive terraforming program. I turn to you for ideas as to what exactly might terraforming Mars would involve. I welcome your competing ideas regarding how and why this would be possible OR impossible, however coldly realistic or creatively far fetched they might be [;D]
I am aware of Mars' lack of a molten core and a sizeable moon and of the consequences involved for such a young atmosphere. Obviously, for the story to take place, I make a basic assumption: terraforming Mars with a breathable atmosphere IS possible, even if this means that the slow loss of atmospheric gasses due to low gravity makes the terraforming process necessarily ongoing.

Thanks a lot,

lungo

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Offline Colin2B

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Re: How could we make an atmosphere in Mars?
« Reply #1 on: 05/07/2015 09:49:51 »
Im assuming any workable process would need to be biological eg algae or bacterial vats to get started, moving on to plants that can work in oxygen poor conditions. I assume water is available.
Don't know g on Mars so would need to look up to determine which useful breathing gasses would leak.
Look fwd to some interesting suggestions.
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Offline PmbPhy

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Re: How could we make an atmosphere in Mars?
« Reply #2 on: 05/07/2015 11:49:28 »
Dear forum,

I am a screenwriter currently working on a story that takes place in Mars several hundred years after the start of an extensive terraforming program. I turn to you for ideas as to what exactly might terraforming Mars would involve. I welcome your competing ideas regarding how and why this would be possible OR impossible, however coldly realistic or creatively far fetched they might be [;D]
I am aware of Mars' lack of a molten core and a sizeable moon and of the consequences involved for such a young atmosphere. Obviously, for the story to take place, I make a basic assumption: terraforming Mars with a breathable atmosphere IS possible, even if this means that the slow loss of atmospheric gasses due to low gravity makes the terraforming process necessarily ongoing.

Thanks a lot,

lungo
From what I read Mars may have once had rivers of water on the surface. See:
http://www.space.com/17048-water-on-mars.html
Once you have water you can easily release the oxygen in it by passing an electric current through it. The electricity to do that can come from solar panels or nuclear power plants like the ones on a sub or aircraft carrier.

Another idea would be to release the oxygen from CO2 using cyanobacteria. See:
http://www.universetoday.com/117610/student-team-wants-to-terraform-mars-using-cyanobacteria/
« Last Edit: 05/07/2015 12:01:56 by PmbPhy »

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Offline alancalverd

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Re: How could we make an atmosphere in Mars?
« Reply #3 on: 05/07/2015 12:11:13 »
I strongly advise reading Andy Weir's book "The Martian". The story is a concatenation of carefully constructed cockups and cliffhangers but the underlying science has been very well researched.

There's little point in making the entire atmosphere breathable, any more than we have tried to make the whole surface of the earth like Yorkshire (why Yorkshire? Ask any Yorkshireman!) People only live on a tiny fraction of the dry bit, which itself is only about 25% of the surface, and we are mostly constrained by the need for potable water.
« Last Edit: 05/07/2015 12:15:14 by alancalverd »
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Offline PmbPhy

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Re: How could we make an atmosphere in Mars?
« Reply #4 on: 05/07/2015 13:23:34 »
Quote from: alancalverd
There's little point in making the entire atmosphere breathable, any more than we have tried to make the whole surface of the earth like Yorkshire (why Yorkshire? Ask any Yorkshireman!) People only live on a tiny fraction of the dry bit, which itself is only about 25% of the surface, and we are mostly constrained by the need for potable water.
I don't see it that way. Assuming that the pressure can be maintained at something similar to earth then having an entire atmosphere over the entire planet has several benefits such as being able to fly everywhere over the planet in regular simple aircraft. It also allows people to spread out their living habitats anywhere on the planet and not simply within a container where the atmosphere is maintained. There is also a psychological benefit of having an open atmosphere rather than living in a bubble such as a feeling of security where one doesn't have to worry about the bubble breaking or leaking. Then there's the possibility for rain which can water huge crops in farming areas. I can go on and on but that illustrates my point. The idea of terraforming is not simply to make living on Mars physically possible but that one can eventually have an environment approaching that of earth. We evolved on earth so its natural to want to live in an environment as close as possible to that of earth.

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Offline evan_au

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Re: How could we make an atmosphere in Mars?
« Reply #5 on: 05/07/2015 14:50:00 »
I know you want to produce something original, but you could do worse than to look at some well-researched prior art - Kim Stanley Robinson's Mars trilogy.
Starting with todays red Mars, this series imagines a progression through the primary colors to the greening of Mars, and eventual production of a blue ocean.

Of course, we now know more about Mars than in the 1990s when this series was written - for example, we know that there is a layer of frozen water under the red dusty surface of Mars.

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Offline PmbPhy

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Re: How could we make an atmosphere in Mars?
« Reply #6 on: 05/07/2015 15:24:43 »
Quote from: evan_au
... - for example, we know that there is a layer of frozen water under the red dusty surface of Mars.
Correction. We speculate that there's water there. We don't know it for certain.

Where did you get the idea that we "knew it" as some sort of fact?

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Offline David Cooper

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Re: How could we make an atmosphere in Mars?
« Reply #7 on: 05/07/2015 18:11:05 »
What you need to research is how long a thick atmosphere could be maintained before it's blown away by the solar wind and you lose the ability to produce more gas to replenish it. It may be that you can get enough gas out of rocks to keep going for billions of years, in which case that could be the best approach - a thick atmosphere is useful for many reasons.

If that's impractical though, it would be best to put up lots of glass domes, and if one gets smashed by a meteorite every now and then, that's a small loss. It's no riskier for any individual than being in the ISS, so you wouldn't need to spend the whole time living in fear. Also pay attention to the problem of the moons - at least one of them is in an orbit that's losing altitude over time and it will collide with Mars at some point, leading to lots of debris crashing down potentially for thousands of years afterwards which will smash all your glass, so you're going to have to see if you can find a way of boosting its orbit to prevent this from happening.

Another thing to think about is the health problems of living with reduced gravity. Some people may naturally cope better than others, and you can probably breed a new subspecies of humans fairly quickly to eliminate the problem altogether, but in the meantime you could use rotating accommodation modules which replicate the feel of Earth's gravity at the edge, but be aware that this rotation can be felt by the balance sensors in the ear and it will make people feel ill, unless they can be medically modified - perhaps a drug can be found to keep the problem under control.

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Offline alancalverd

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Re: How could we make an atmosphere in Mars?
« Reply #8 on: 05/07/2015 18:39:44 »
Solar wind is not the problem. Lack of gravity is. If your atmosphere is at a breathable temperature it will diffuse away into space if not held by sufficient gravitation (or a plastic bubble).

Other than that, low gravity isn't a serious physiological problem as long as you don't want to return to Earth. The body adapts by providing just enough bone calcification to meet demand: we see this in the  hip bones of policemen and agricultural workers, whose regular shock loading due to walking or lifting  results in very dense pelvic bone, and in the femurs of people with inadequately-designed hip implants where the implant relieves stress to the point that the femoral bone is reabsorbed. So our successors may walk OK on Mars but resemble jellyfish on Earth.     
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Offline lungo

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Re: How could we make an atmosphere in Mars?
« Reply #9 on: 06/07/2015 03:52:34 »
Thank you Colin2B, PmbPhy for your suggestions. The cyanobacteria suggestion definitely puts in place a step that I was missing, namely the initial production of an atmosphere appropriate for the survival of plants and trees that can be found in high altitude environments on Earth.
Some interesting questions have arisen which need to be addressed:

Basic assumptions:
a-the terraforming process has led to the creation of a breathable atmosphere that, although thinner than here on Earth, allows atmospheric flight and survival without air domes and/or bubbles
b-water has not only been found but, although frozen, is also plentiful
c-as pointed out by Colin2B a nuclear reactor (maybe fission, but since the story takes place several hundred years in the future, why not fusion?) is used to turn the ice into flowing water (and therefore small streams and lakes) steam (leading to the establishment of some form of precipitation pattern which in turn would determine the areas suitable for agriculture, resource exploitation and life in general) and finally electrolysis, contributing to the atmosphere building effect of cyanobacteria and transplanted vegetation suitable for the prevailing conditions
d-great point about bone mass loss by alancalverd: I assume the lower gravity would lead to easily broken bones when human Martians visit Earth, maybe they could use some sort of electromechanical exo-skeleton such as the ones already being produced for industrial use (https://www.youtube.com/watch?v=VSzvVXiWkSg)
e- another interesting (and funny) consequence of the difference between both planets would be that Earth-born humans suffer from altitude disease when visitng Mars, but Mars-born humans get drunk on oxygen when visiting Earth (would this actually happen?)

Question: what about the nitrogen, which makes up the bulk of our atmosphere? being an element it cannot be synthesised but maybe it could be produced from another existing minerals on Mars? if not, could it be replaced with another gas or is it necessary for our organism?
 

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Offline chiralSPO

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Re: How could we make an atmosphere in Mars?
« Reply #10 on: 06/07/2015 04:15:37 »
The Martian atmosphere only has a few percent of nitrogen (just under 3%), but the whole atmosphere is about 1% as dense as our own (and ours is almost 80% nitrogen, 20% oxygen), so Mars only less than 0.035% of the nitrogen that we have on Earth. You would need to produce a lot of oxygen to get a reasonable pressure.

It might be possible (in a very sci-fi way) to produce argon, which is about 1% of our own atmosphere, and could be an inert gas to increase the overall pressure. Presumably there are some chloride minerals on Mars, and about 25% of chlorine is an isotope with a mass of 37 (37Cl), which can be converted into argon (which is non-toxic, whereas chlorine gas is not so healthy in high concentrations). The trick is reacting the chlorine with neutrinos (which is currently a good way to detect neutrinos, but not a practical way of making argon, by any measure--however, it could potentially be possible to make this a more efficient process...) Argon would also be somewhat more likely to stick on Mars (molar mass of 40, which is almost the same as CO2, which is 44, and substantially more than nitrogen, which comes in at a paltry 28... Unfrotunately, oxygen is 32 and water is 18, so as pointed out above--holding on to a thick atmosphere at a reasonable temperature will not be very easy, given the low gravity on Mars.)

I think bubbles or space-suits would likely be a must on Mars.

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Offline chiralSPO

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Re: How could we make an atmosphere in Mars?
« Reply #11 on: 06/07/2015 04:28:59 »
Another thought (probably a bad one, but hear me out)

Perhaps crashing the two Moons, as well as several asteroids from the asteroid belt, into Mars could help (a little) on several fronts:

(1) increased mass-- at 6.4x1023 kg, Mars is only about 11% as massive as the Earth is, . Adding Phobos (1.1x1016 kg), and Deimos (1.5x1015 kg), Ceres, (9.4x1020 kg) and Vesta (2.6x1020 kg)wouldn't make that much of an increase, but it wouldn't hurt either. (in all about a 1% increase in mass...) Collecting the whole asteroid belt could increase the mass by about 3%...

(2) increased temperature--the heat released from so many bodies crashing into mars would substantially increase the temperature (possibly too much, I don't know)

(3) more water and useful minerals--possibly better to mine the minerals before crashing them into Mars and distributing them across the whole planet, but the water (if it doesn't all vaporize and go into space), could turn into oceans.

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Offline lungo

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Re: How could we make an atmosphere in Mars?
« Reply #12 on: 06/07/2015 05:00:33 »
Another thought (probably a bad one, but hear me out)

Perhaps crashing the two Moons, as well as several asteroids from the asteroid belt, into Mars could help (a little) on several fronts:

(1) increased mass-- at 6.4x1023 kg, Mars is only about 11% as massive as the Earth is, . Adding Phobos (1.1x1016 kg), and Deimos (1.5x1015 kg), Ceres, (9.4x1020 kg) and Vesta (2.6x1020 kg)wouldn't make that much of an increase, but it wouldn't hurt either. (in all about a 1% increase in mass...) Collecting the whole asteroid belt could increase the mass by about 3%...

(2) increased temperature--the heat released from so many bodies crashing into mars would substantially increase the temperature (possibly too much, I don't know)

(3) more water and useful minerals--possibly better to mine the minerals before crashing them into Mars and distributing them across the whole planet, but the water (if it doesn't all vaporize and go into space), could turn into oceans.

Loving it, loving the whole thing mate. Since I'm writing a piece of sci fi it doesn't need to be feasible, merely verisimilar. Fits nicely with your previous comment on the need to generate a whole lot of gas to achieve sufficient pressure. Had thought about lassoing a comet and crashing it on the surface, but crashing moons definitely has a more heroic undertone to it.

questions:
-wouldn't it rip the planet apart?
-wouldn't it lead to extremely wild weather without a stabilising gravitational influence such as our own Moon exerts on Earth?

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Offline Colin2B

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Re: How could we make an atmosphere in Mars?
« Reply #13 on: 06/07/2015 08:50:07 »
Have you considered that not everyone would be in favour of destroying this pristine wilderness? Your terraforming team might contain at least one saboteur, but who is doing the damage, human or underground Martians?

and the misguided shall lead the gullible,
the feebleminded have inherited the earth.

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Offline lungo

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Re: How could we make an atmosphere in Mars?
« Reply #14 on: 06/07/2015 09:22:49 »
Great point Colin2B. The terraforming is mostly done by the time the story takes place and Mars is inhabited by 2nd and 3rd generation native human beings, descendants of the original settlers who took part in the final stages of the terraforming process, who proudly call themselves Martians. The exploration of their cultural identity and their relationship with the species' home planet are central elements of the plot, including the appearance of a growing, extremist faction fighting for environmental preservation, self rule and independence from Earth through terrorism and sabotage of ongoing immigration efforts.
So although we don't focus on the team conducting the terraforming the idea is to deal with its consequences.

About my Martians: What does it mean to belong to a species that originally evolved in a different planet? Is Mars’ specific environment, with its lower gravity and thinner atmosphere, taking human evolution on a different path? If so, are they still humans?
I welcome speculation on these matters
« Last Edit: 06/07/2015 09:41:19 by lungo »

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Offline Colin2B

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Re: How could we make an atmosphere in Mars?
« Reply #15 on: 06/07/2015 10:54:34 »
About my Martians: What does it mean to belong to a species that originally evolved in a different planet? Is Marsí specific environment, with its lower gravity and thinner atmosphere, taking human evolution on a different path? If so, are they still humans?
I welcome speculation on these matters
Although this is a physiology question, physics has a big influence.
If the air has less oxygen would they develop larger lungs or is it more likely that blood would change as in high altitude peoples on earth.
Would they grow taller because of lower gravity, effects on musculature, heart efficiency etc
If the gas mix is different eg Argon as suggested by ChiralSPO then you might get an effect on voice pitch similar to breating high Helium mix when diving.
Would the difference in UV have an effect on skin function and colouring etc
See also bone mass as suggested by AlanCalverd


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the feebleminded have inherited the earth.

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Offline PmbPhy

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Re: How could we make an atmosphere in Mars?
« Reply #16 on: 06/07/2015 11:07:58 »
Quote from: alancalverd
Solar wind is not the problem. Lack of gravity is. If your atmosphere is at a breathable temperature it will diffuse away into space if not held by sufficient gravitation (or a plastic bubble).   
And what would that be for Mars? Consider the fact that Earth has a surface pressure of about 1 bar whereas Venus has a surface pressure of about 92 bars. The mass of Venus is about 80% the mass of Earth. The atmosphere or Venus didn't exactly diffuse away into space.

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Offline PmbPhy

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Re: How could we make an atmosphere in Mars?
« Reply #17 on: 06/07/2015 11:13:08 »
Quote from: lungo
b-water has not only been found but, although frozen, is also plentiful
Why are you treating this as a fact when at present it is merely speculation? Where did you hear or read that water was found on Mars. All I've seen is observations which might imply that water was there. That's about it.

To help in this I just wrote to NASA to find an answer to the question of whether its a fact that there is water on Mars or if its just our best guess at this point.
« Last Edit: 06/07/2015 11:16:18 by PmbPhy »

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Offline lungo

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Re: How could we make an atmosphere in Mars?
« Reply #18 on: 06/07/2015 11:33:57 »
Quote from: alancalverd
Solar wind is not the problem. Lack of gravity is. If your atmosphere is at a breathable temperature it will diffuse away into space if not held by sufficient gravitation (or a plastic bubble).   
And what would that be for Mars? Consider the fact that Earth has a surface pressure of about 1 bar whereas Venus has a surface pressure of about 92 bars. The mass of Venus is about 80% the mass of Earth. The atmosphere or Venus didn't exactly diffuse away into space.

Really interesting line of discussion, eager to see where it leads.

About my Martians: What does it mean to belong to a species that originally evolved in a different planet? Is Marsí specific environment, with its lower gravity and thinner atmosphere, taking human evolution on a different path? If so, are they still humans?
I welcome speculation on these matters
Although this is a physiology question, physics has a big influence.
If the air has less oxygen would they develop larger lungs or is it more likely that blood would change as in high altitude peoples on earth.
Would they grow taller because of lower gravity, effects on musculature, heart efficiency etc
If the gas mix is different eg Argon as suggested by ChiralSPO then you might get an effect on voice pitch similar to breating high Helium mix when diving.
Would the difference in UV have an effect on skin function and colouring etc
See also bone mass as suggested by AlanCalverd

LOL! Love the high-pitch voices! Had considered their decreased bone mass, and they would need to wear some sort of exo-skeleton while visiting Earth as mentioned above. Had also considered the increased pulmonary capacity, and this brings me back to an unanswered question from above: if this was the case, would martians get drunk on oxygen when visiting Earth?

Quote from: lungo
b-water has not only been found but, although frozen, is also plentiful
Why are you treating this as a fact when at present it is merely speculation? Where did you hear or read that water was found on Mars. All I've seen is observations which might imply that water was there. That's about it.

To help in this I just wrote to NASA to find an answer to the question of whether its a fact that there is water on Mars or if its just our best guess at this point.

The comment is absolutely correct, although I will point out that I never called it a fact, merely an assumption that allows me to propel the script forward. Without water in Mars (whether because it was once liquid and was lost to space as it evaporated or because it was never there and recent observations are misleading) the sustainability of life is beholden to more ambitious schemes such as the ones discussed above: lassoing and crashing a comet/s on the surface or, as per chiralSPO's spectacular idea, crashing Phobos and Deimos into Mars to create oceans. I fully appreciate the criticism though, and thank you for writing to NASA seeking an answer.

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Offline PmbPhy

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Re: How could we make an atmosphere in Mars?
« Reply #19 on: 06/07/2015 11:56:03 »
Quote from: lungo
The comment is absolutely correct, although I will point out that I never called it a fact, merely an assumption that allows me to propel the script forward.
You wrote water has not only been found which means that it was stated as a fact. When one write something like that it's assumed that the author intended it to be taken as true. It makes no difference whether you used the word "fact". It's the context in which you wrote it and the way you phrased it which makes it appear as though you were saying that water had actually been found. Otherwise you would have said something like "they think water may be on mars".

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Offline lungo

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Re: How could we make an atmosphere in Mars?
« Reply #20 on: 06/07/2015 12:28:33 »

Basic assumptions:
a-the terraforming process has led to the creation of a breathable atmosphere that, although thinner than here on Earth, allows atmospheric flight and survival without air domes and/or bubbles
b-water has not only been found but, although frozen, is also plentiful
c-as pointed out by ...

Mate, the list of bulletpoints rests under a header reading "basic assumptions" Not looking for controversy,  but since you make reference to "the context in which I wrote it" please re visit the first post, in which it is clearly explained that the purpose of the original question is to integrate some informed opinions (more informed than my own, ideally) into what is meant to be a sci-fi script about life on Mars after an extensive terraforming effort. Because the success of such effort is the premise of the script and its starting point some basic assumptions are made, such as the one you point out.

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Offline PmbPhy

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Re: How could we make an atmosphere in Mars?
« Reply #21 on: 06/07/2015 12:41:47 »
Quote from: lungo
Mate, the list of bulletpoints rests under a header reading "basic assumptions"
I understood that. That's why I wanted to know why you assumed that water had been found and not merely been speculated.

Quote from: lungo
.. but since you make reference to "the context in which I wrote it" please re visit the first post, ..
No worries. I know what I'm doing and I read what you wrote already so you need not repeat it. The point I was trying to make clear was that you wrote this as if these assumptions were what you made about Mars, i.e. what you assumed to be true. If you meant that you were postulating them as part of the story then that's a different thing altogether.

Quote from: lungo
in which it is clearly explained that the purpose of the original question is to integrate some informed opinions (more informed than my own, ideally) into what is meant to be a sci-fi script about life on Mars after an extensive terraforming effort. Because the success of such effort is the premise of the script and its starting point some basic assumptions are made, such as the one you point out.
The point that you failed to make clear was that the assumptions stated under "basic assumptions" weren't what you believed to actually be the case but which you made as part of the story. That wasn't clear in any of the posts. Remember that you're talking to physicists and enthusiasts and not sci-fi writers. Don't expect us to write the same way. When there is something that is unclear to be I ask questions and that was the purpose of those questions. E.g. since I know that we don't know that there's water on Mars as a fact then I wanted to know why you assumed it. You could have simply said that you were making it part of the story or you could have told me that you read it somewhere, whatever the case may have been.
Quote from: lungo
Not looking for controversy, ..
No worries. You just have to be prepared for people to ask you questions. Don't get bothered by them. Just answer them as honestly and straight forward as you can. Okay? You seem to think that I'm attacking you when it was never my aim to do so. I've just been at this a long time and wanted to let you know how what you write can be interpreted by a physicist. So when you basically said 'I'm assuming that water has been found on mars' all I wanted to ask was why you assumed (i.e. why you had a basic assumption) that it was so. Okay. So I'm dropping it here and suggest that you do the same since this is not the purpose of the thread. But it was important for me to understand it. After all if we do know that there's water on Mars as a fact then that would make a good part of the story.

Were you aware that Arthur C. Clarke referenced a real life journal article in one of his books to make it more true to life? I suggest that you try to do the same. It makes for better reading.

May I ask what other sci-fi books you've written? You can PM me if you prefer not to tell the entire world.
« Last Edit: 06/07/2015 14:58:14 by PmbPhy »

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Offline evan_au

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Re: How could we make an atmosphere in Mars?
« Reply #22 on: 06/07/2015 14:14:38 »
Quote from: PmbPhy
We speculate that there's water there. We don't know it for certain.
We have some fairly strong hints from the Phoenix mission that there is frozen water near the poles of Mars.
But it's hard to be sure with a sample size of 1.

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Offline PmbPhy

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Re: How could we make an atmosphere in Mars?
« Reply #23 on: 06/07/2015 15:01:10 »
Quote from: evan_au
Presence of shallow subsurface water ice Phoenix mission that there is frozen water near the poles of Mars.
But it's hard to be sure with a sample size of 1.
I don't understand, Evan. If that's the case then why did you write
Quote from: evan_au
...we know that there is a layer of frozen water under the red dusty surface of Mars.
I.e. we know is quite different than it's hard to be sure. If you don't mind me asking, that is? :)

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Offline Colin2B

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Re: How could we make an atmosphere in Mars?
« Reply #24 on: 07/07/2015 00:25:09 »
Going a little off topic.
Have you considered items that might be in short supply and change the way Martians live? We use a lot of plastic, but Mars without access to oil (except by expensive import) might need to find alternatives eg plant fibres, casein plastic from milk, etc.
I don't know the geological make up of Mars but some minerals will be plentiful and others very rare, this will influence what can be made locally.
and the misguided shall lead the gullible,
the feebleminded have inherited the earth.

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Offline alancalverd

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Re: How could we make an atmosphere in Mars?
« Reply #25 on: 07/07/2015 01:01:16 »
Quote from: alancalverd
Solar wind is not the problem. Lack of gravity is. If your atmosphere is at a breathable temperature it will diffuse away into space if not held by sufficient gravitation (or a plastic bubble).   
And what would that be for Mars? Consider the fact that Earth has a surface pressure of about 1 bar whereas Venus has a surface pressure of about 92 bars. The mass of Venus is about 80% the mass of Earth. The atmosphere or Venus didn't exactly diffuse away into space.

A good point. The difference is the chemical composition of the atmosphere and certainly not the solar wind, which is a lot stronger on Venus. Except that the chemical composition of both atmospheres is effectively identical - about 95% carbon dioxide.

So it must be that Mars is so much colder. But Neptune is even colder and has a surface pressure of over 1000 bar.... 

So the answer is...I don't know!

Anyone out there care to enlighten me?
helping to stem the tide of ignorance

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Offline lungo

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Re: How could we make an atmosphere in Mars?
« Reply #26 on: 07/07/2015 02:24:04 »
Going a little off topic.
Have you considered items that might be in short supply and change the way Martians live? We use a lot of plastic, but Mars without access to oil (except by expensive import) might need to find alternatives eg plant fibres, casein plastic from milk, etc.
I don't know the geological make up of Mars but some minerals will be plentiful and others very rare, this will influence what can be made locally.

Good point mate. It is a major plot point that, because oil and workable ore deposits of basic minerals on Earth were depleted a long time ago (oil replaced by better bioplastics, carbon composites) export of refined minerals is a major component of the Martian economy. Because Mars isn't entirely self sufficient and many components and supplies necessary for heavy industry are still imported from Earth this co-dependency makes the push for Martian self-determination all the more complicated, both for people on Mars and Earth.

There's suggestive evidence of large deposits of iron, aluminum, titanium and magnesium in Mars found by Spirit and Opportunity, the rovers also found trace amounts of chromium, cobalt, nickel and zinc but maybe such deposits aren't rich enough to be exploited, again putting Mars further away from sef-sufficiency. Also, haven't found any reference to existing phosphates, essential for agriculture in what could be a relatively barren soil. Maybe a major Martian import is guano?

I'm working on the basis that regular supplies from Earth arrive in Mars faster and cheaper than they would in the present day: supplies from Earth are put in orbit via a space elevator, loaded onto a ship that takes the cargo to Mars (fusion propulsion is the working assumption) On Mars the lower gravity allows heavy shipments of mined minerals, refined on site, to be loaded onto unmanned capsules and put in orbit by a giant rail gun, once there they are directed towards Earth by their own thrusters. Upon arrival on Earth's orbit the capsule is taxied, docked onto the space elevator platform and unloaded. The same capsule is loaded again and used to carry supplies from Earth to Mars, then launched from the ship and towards the Martian surface, using a parachute and the aforementioned thrusters to ease the touchdown. Although the capsule is reusable the guides that make contact with the rails on the rail gun when launching from Mars need to be changed every time.

Things to wonder about: Oil on Earth and Mars replaced by better bioplastics than we have today?  Would it be easier to transport entire heavy industrial facilities a few pieces at a time (thinking furnaces, foundries, forges) or build them from scratch? Regarding Mars ore deposits, what am I missing? What is and isn't there that would be essential?
Also (and I'm really loving writing about this bit) any better ideas on how the import/export operation to and from Mars would work?
Waiting for some suggestions!

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Offline evan_au

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Re: How could we make an atmosphere in Mars?
« Reply #27 on: 07/07/2015 10:40:36 »
Quote from: evan_au
...we know that there is a layer of frozen water under the red dusty surface of Mars.
I remember seeing the images taken by a Mars lander, showing a white patch blasted out by the landing rockets, and the white scrapes made by the sample collector - this is what led me to think that there definitely was ice on Mars.

But when I looked up which Mars lander (Phoenix), and the conclusions from its experiments, it appears that its not 100% certain that it was water ice, with some alternative hypotheses floating around (eg perhaps it was salty water or dry ice=CO2).

Apparently, some of the instruments did not work perfectly, and samples got stuck in the in-tray, making the analysis less than definitive.

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Offline David Cooper

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Re: How could we make an atmosphere in Mars?
« Reply #28 on: 07/07/2015 18:40:11 »
How certain are you, Alan, that the solar wind isn't a key factor in depleting the atmosphere on Mars? I've heard it blamed for it on science programmes which point out that the magnetic field on Mars is extremely weak and incapable of deflecting the solar wind away in the way that the Earth's does.

On the issue of whether there's water on Mars or not, there's plenty of evidence that something liquid has been running about over the surface in very recent times and will still be around in large quantities under the surface, and water is the most likely candidate. It certainly isn't CO2 or methane.

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Offline chiralSPO

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Re: How could we make an atmosphere in Mars?
« Reply #29 on: 07/07/2015 20:51:14 »
Venus doesn't have a magnetic field either (though I suppose its CO2 and SO2 atmosphere is less susceptible to depletion by solar wind...)

Mars has a substantially weaker gravitational field than Venus, Earth or Neptune. On the other hand, it is also about 5 times as massive as Titan, which has plenty of atmosphere!

It must not be a very simple explanation, but my guess is that a combination of the low mass, weak magnetic field, relative proximity to the sun, temperature, and initial composition of the atmosphere has lead to the present state of the Martian atmosphere.

It would appear that much of its CO2 is solidified, and most of its nitrogen is lost...

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Offline fmartinie

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Re: How could we make an atmosphere in Mars?
« Reply #30 on: 08/07/2015 01:42:01 »
its possible to create a sort of massive dome and from the inside of that dome you could create an artificial environment that is suitable for life and maybe an atmosphere ? depends on how you want your story to go but this is just another idea.

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Offline lungo

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Re: How could we make an atmosphere in Mars?
« Reply #31 on: 08/07/2015 07:33:09 »
Hi everyone,

Found this really interesting paper on technological requirements for the terraforming of Mars,
http://www.users.globalnet.co.uk/~mfogg/zubrin.htm
As laid out here the process would start by generating a greenhouse effect on Mars, either through crashing ammonia rich comets on the surface of by artificially producing large quantities of CFC's directly from a facility on the Martian surface, although this last effort would most likely involve at least a rotating crew of people operating it.
Second stage would start with the deployment of large mirrors of mylar or a mylar-like material (starting at a "modest" 125 km radius) to reflect sunlight onto one or both poles, likely candidates for the presence of frozen CO2 and/or water. Solar wind would prevent the mirror from orbiting and keep it in a relatively stationary position, allowing the concentration of reflected sunlight in a specific area of the planet causing a steady rise in local temperature. While contributing to raise pressure it would create an environment appropriate for moving onto stage 3, in which suitable vegetation and/or micro-organisms (perhaps genetically engineered) could thrive and self-propagate.
Most convincing study I've found so far, please let me know how you like it. An interesting observation is the fact that a mirror that big couldn't possible be launched from Earth ready to deploy, but rather would need to be assembled in zero gravity.

On a different note:

Venus doesn't have a magnetic field either (though I suppose its CO2 and SO2 atmosphere is less susceptible to depletion by solar wind...)


Sorry if the question is a bit basic, but why would certain gasses be more susceptible to solar wind than others?
The question of why bodies of a similar mass have held on to an atmosphere while Mars hasn't is definitely one the most interesting. On the matter of the absence of a strong magnetic field (as far as my understanding goes due to the lack of a molten core) why is the core solid? is the pressure itself what keeps the Earth's core molten? if so, is the lower mass of Mars to blame? and is the chemical composition of the core itself a crucial factor?
« Last Edit: 08/07/2015 07:47:25 by lungo »

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Offline lungo

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Re: How could we make an atmosphere in Mars?
« Reply #32 on: 08/07/2015 07:44:03 »
its possible to create a sort of massive dome and from the inside of that dome you could create an artificial environment that is suitable for life and maybe an atmosphere ? depends on how you want your story to go but this is just another idea.

Hi there. This was an initial consideration actually, but the presence of a breathable atmosphere gives me a much more interesting scenario to work with given the direction the story takes. Perhaps the creation of such a dome does prove necessary during stage 1 as a base to host the people working on the CFC factory mentioned above.