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Thinking of terraforming a localized region, how (if possible) can we create an artificial high pressure zone, whether practical or not,

Initially I thought, perhaps we can arrange heatsinks to induce a pressure trap heated with laser arrays closer to the Sun. Perhaps a tunable cyclonic system or harmonic heat waves along the equator creating an interference pattern focused toward one region. I am unsure about the merits and feasibility of different methods.

This is for a video game, so does not need to be scientifically plausible given our technology and resources, though of course it is encouraged.

Certainly there will be gas lost. In the game Mars has a ring system with any desired ices/minerals designed by tractoring astroids into collisions. And the handy space elevator is available so you don't need to worry about supplies unless you want to.

Part of the larger idea is that if you can sustainably terraform a small open area, leaked gas will passively pressurize the planet in the long run.

UPDATE

I find all the answers gave me good feedback and could have a place in the game setting. I've choosen Loren Pechtel's answer because

  • most detail, effort and thought out specs
  • not as plausible as subterranean areas but gives an open-air solution thats scientifically feasible-esque
  • massively deforming mars's shape gives me some global-scale plot devices to work with

I am considering combining Loren's answer with the small neutron star and gravity tech from axsvl77's answer to reduce the size requirements and retain yet another plot device.

Finally I thought, early martian colonies will likely be subterranean due to practicality. Considering Fayth85's answer, we can have a small established underground culture have conflict with the newly formed surface culture. Perhaps different cultural movements between the time early and later technologies formed cause still greater differences.

Thanks for all the feedback!

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    $\begingroup$ A well deep enough? $\endgroup$ – SF. Jul 19 '16 at 8:18
  • $\begingroup$ @SF oh my how simple nice $\endgroup$ – Garet Claborn Jul 19 '16 at 21:01
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    $\begingroup$ Welcome to Worldbuilding (as a non-lurker)! That's very imaginative; I hope you participate more here. $\endgroup$ – JDługosz Jul 19 '16 at 21:15
  • $\begingroup$ @SF But the sides of the well are in effect walls. I would go with a very deep crater. $\endgroup$ – Loren Pechtel Jul 19 '16 at 21:59
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    $\begingroup$ Hey--my solution doesn't make a Pac-Man shape! It's simply a sphere with a slice off the side. Obviously a Pac-Man shape means less material removed but you said no walls and a Pac-Man type cut has something approximating walls. $\endgroup$ – Loren Pechtel Jul 22 '16 at 19:21
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A solution that should "work" (there will be some leakage that needs to be replenished) but requires some truly massive engineering.

Slice off a chunk of the planet—the resulting surface is truly flat, not merely "flat" like we see the surface of the planet as.

Putting some numbers to it: The scale height of the Martian atmosphere is 11.1km, the pressure is 600 pascals, Earth normal is 101 kilopascals. Thus we need to raise the pressure by 168×. For each 11.1 km we go down the pressure goes up by a factor of e. We need 5.12× this to raise it to Earth normal. Thus the maximum depth of our slice must be 56.8 km. To get a larger area of Earth-normal pressure you might want to cut deeper but then curve the bottom of your cut to maintain this 56.8 km depth.

Supply sufficient air, you have your place where humans can walk unprotected and with no walls whatsoever. Beware that the Martian gravity is too weak to hold onto this air, it will slowly leak away. Note that while the ground is truly flat (unless you go with the bulge option) it will feel like you're walking slightly uphill as you walk away from the center.

Beware that this is a truly massive cut, it's going to be over 1,200 km across. Walking from the center the 600 km to the edge you fill find the pressure dropping from Earth-normal to Mars-normal. I also suspect that the crust of Mars isn't strong enough to avoid collapsing this cut.

Edit: I realize there's a problem with my numbers here. I looked up the scale height for the Martian atmosphere but it's not right. Scale height is a property of gravity and molecular weight—and we are replacing CO2 (weight 44) with oxygen (weight 32) and probably nitrogen (weight 28) for an average of 28.8. Unfortunately, I'm out of my depth at this point. I know the slice needs to be deeper but I don't know by how much.

Using argon (weight 40) in place of nitrogen will help a bit but where are you going to get that much argon?? Krypton would be even better at almost 84 (the slice is shallower) but finding enough is an even bigger issue. Xenon at 131 would be even better but still harder to find.

Unfortunately, I'm not finding element abundance in numeric form and I'm left with eyeballing it off a Wikipedia chart. Argon seems to be 1/100th as common as nitrogen, krypton 1/1000th of argon and xenon 1/10th of krypton.

Edit again: Amazingly, I find that despite it being an exponential function scale height simply has the molecular mass in the divisor.

Thus for a typical oxy-nitrogen atmosphere we have a scale height of 17.7 km and our slice must go 90.6km into Mars and now our cut is 1,560km across. At our original cut of 56.8 we are 1.9 scale heights higher up--atmospheric pressure is only 15% of Earth-normal. You'll need to be breathing pure oxygen to survive this--and that would be a Disneyland for fire.

For oxy-argon we are looking at a molecular weight of 38.4 and a scale height of 13.3km for 42% of Earth-normal pressure--like Earth at 22,000'. Barely survivable.

Oxy-krypton gives a molecular weight of 73.6 for a scale height of 6.9km for 8.2 scale heights with the same cut. 22x Earth-normal pressure--that's about 210m into the ocean. This gas mix and pressure is lethal. You will get Earth-normal pressure with a slice only 35.3km deep. Note, however, that while I can't find good data it looks like you'll get some fairly serious rapture of the deep issues from breathing this.

Oxy-xenon gives a molecular weight of 111.2 for a scale height of 4.6km. I won't even worry about the results with the same cut, they're obviously lethal. A 23.6km cut gives Earth-normal pressure but this gas mix looks like it causes lethal rapture of the deep problems.

I'm afraid you're stuck with the deeper cut.

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  • $\begingroup$ you had me interested at 'slice of a chunk of the planet'. ok so with mars being ~3400km deep, the average crust is around 50km i think. At this point we're in the mantle a bit. That complicates things but it also opens up some possibilities..hmm.. The one tinsy little problem being gravity and collapsing the cut. Even if we made a sloped crater that deep I'm not sure if Mars would allow it seeing as that's far greater elevation difference than Valles Marineris or Olympus Mons. Maybe the magma could form supports... Physics aside it makes for a very dramatic setting so thats very good ;p $\endgroup$ – Garet Claborn Jul 19 '16 at 22:56
  • $\begingroup$ Going half the distance might be enough. At that depth we could retain most heavier gasses without filling the entire hole and pressurize the area more easily. Though I did add a note in response to your comment about resupplying air. $\endgroup$ – Garet Claborn Jul 19 '16 at 22:58
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    $\begingroup$ @GaretClaborn Mars' mantle is solid, not liquid. The fact that we have probably nicked it doesn't make the cut into a volcano. The elevation change is beyond what my understanding is of what Mars can support--but it's also so big that the gradient is low and I would think it could support more than the maximum mountain height. $\endgroup$ – Loren Pechtel Jul 20 '16 at 3:23
  • $\begingroup$ My only major issue is that, Mars being a planet (rather than a dwarf planet) would be in Hydrostatic Equilibrium. Therefore, for this to work, you would have to reinforce Mars. It would in fact be easier to blow up Mars and rebuild it from scratch...I would advise using a Freeman Dyson Planetary Spin Motor. $\endgroup$ – Aron Jul 20 '16 at 3:56
  • $\begingroup$ @LorenPechtel aaah right i realized it no longer had plate tectonics but for some reason those dots didnt connect. well that's great! good thinking $\endgroup$ – Garet Claborn Jul 21 '16 at 5:58
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I've got a few scenarios for you, some of which are based on other works of fiction.

But let's start with the WHERE After all, location, location, location, right?

There's only terraforming deep crevasses, or impact crater. This was done in 'Hoshi no Koe' (lit: 'voices of a distant star', an anime I've watched). Basically you either locate, or dig a large hole, and focus only on that. Advantages are that the walls will act as a natural insulation so that there's only one 'escape route' should failsafes... well, fail. Less damage to mitigate. I'm not overly familiar with Martian topography, but I believe there was a large canyon that might be ideal for just that, though it might well be much larger of an area than you were counting on.

Right, so how?

A few options off the top of my head. First is the ever popular force field if you want the Sci-Fi route. It would take some major power to keep that sucker running, but it's not impossible. Do keep in mind that solar-farming is less effective on Mars than on Earth, so you'd need a solid energy source that is renewable. Though, I do remember reading the the greenhouse gases we oh so hate here on Earth, would help Terraform Mars in the long run, so maybe that won't be such a bad thing for you.

Hmm, you could always build your new 'environment' underground. Either by locating a subterranean cave system, or digging one yourself. After all, you need to contend with cosmic radiation there, so the more material between you and the cosmos, the better (unless you can think of a way to keep that out). My amateur advise would be storing the water above you, so that the rays hit the water before it hits you, but that's just me. This does have the drawback of plausible leaks, so you'd need to do something about that. And it would be an undertaking that makes building a city from scratch here on Earth look like 'the projects'.

Any thing using air directly will likely fail, purely because air is apt to escape regardless of what is tried. Keep in mind that the problem on Mars is the dangerously low atmospheric pressure (other than temperature). You could try to 'fill the planet' with air, but even that is apt to fail, simply because you'd need to heat up a pocket of it, and that will make it lighter than the surrounding air and therefore rise. Without a 'retaining wall', it's a guaranteed fail.

Hope this helps ^_^

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  • $\begingroup$ These are some good suggestions.. the naturally formed large hole method seems to be one of the most plausible to start with. On the other hand I still wonder if some sort of accelerated gas would be cheaper than a literal force field. Adding a note to the post about replenishing gas, but I'm trying to keep the loss minimized and force fields do a good job there. However using air directly is a very strong goal here lol. $\endgroup$ – Garet Claborn Jul 19 '16 at 22:39
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    $\begingroup$ "Magic did it?" $\endgroup$ – Fayth85 Jul 19 '16 at 22:46
  • $\begingroup$ well yeah.. but i didnt want to go all 'The Martian' on it unless i have to xD the force field is a pretty well accepted game component tho $\endgroup$ – Garet Claborn Jul 19 '16 at 22:47
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Same as the way we do it on Earth: With Gravity!

The easy way is to generate artificial gravity in your development zone. Then any air you release will stay nearby. Just need the technology to artificially increase gravity!

While you're at it, make the artificial gravity directional, so that it doesn't destabilize the structure of the planet you are on. Or even better, make the gravity specifically more attractive for gasses than non-gasses. That way, the planet will slowly pull gases in from off-planet.

It is fiction, so there are a ton of ways to vary this idea.

Edit: How to implement this? Realistically, at this time we (I?) don't understand the source of gravity well enough for me to speculate about how to build this.

For a story, I would use a 'graviton concentrator' to create a meta-material with semi-gravi-ductor logic control, like a silicon-semiconductor. Once the semi-graviductor operates, I would amplify the gravity wave through an ultra-dence on-board nano-sized neutron star.

For directional control, I would isolate anti-gravitons in a similar manner to create a reciprocal anti-gravity device, and position it such that creates destructive interference where I don't want increased gravity.

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  • $\begingroup$ True enough! I wonder if you have any suggestions for theoretical or fictitious, large-scale gravity devices? $\endgroup$ – Garet Claborn Jul 21 '16 at 7:14
  • $\begingroup$ @GaretClaborn I added something; what do you think? Still new to SE world building. Should I elaborate further? $\endgroup$ – axsvl77 Jul 21 '16 at 7:38
  • $\begingroup$ One note- in your final paragraph, you would want to create de- structive interference instead of constructive. $\endgroup$ – Delioth Jul 21 '16 at 18:15
  • $\begingroup$ A small neutron star is pretty interesting. If we're talking about directing gravity, I wonder about using such metamaterials to create a sort of fluted container.. like the shape of an EM drive.. to house the star and also constrain the direction affected.Could be a good way to have an additional bad ending to the game as well. o_o $\endgroup$ – Garet Claborn Jul 22 '16 at 18:43

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