Author Topic: Envisioning Amazing Martian Habitats  (Read 105513 times)

Offline uhuznaa

  • Full Member
  • *
  • Posts: 104
  • Liked: 57
  • Likes Given: 8
Re: Envisioning Amazing Martian Habitats
« Reply #20 on: 10/12/2016 02:43 PM »
Ice Dome Construction for Large Scale Habitats on Atmosphere Less Bodies

as attached with examples
Method only works at high altitudes on Mars.
You need to insulate the dome if you want to have above 0 temperatures inside.
I believe there is a limit to the altitude the ITS can land because it requires aerodynamic braking.  Do the two match up?
On the other hand, the mechanical characteristics of ice can be improved significantly by additives, to create a material similar to fiber reinforce plastics, Pykrete.  The same dome could be build from the outside, rather than from the inside, using hoses and a supply of fibrous material. 
Wouldn't be transparent, though, although perhaps translucent, depending on the fiber used.
What is the cheapest fiber than can be obtained/produced on Mars?

What is the heat balance of a Martian building?  Houses are not very energy intensive, but the heat load from an efficient plantation may be quite high, for example.  A greenhouse (or more aptly a grow house) in ice might be a significative challenge, at the lighting levels can reach hundreds of watts per m2.  Intensive grow houses on Earth require active cooling. 
So you may have a cheap building, but if it requires constant active cooling and a radiative cooling system, it may not be the safest place to live.

Thermal management will just be one of the problems you will have to solve. But if you're sitting in the midst of a glacier stretching for tens of miles and half a mile thick, some water coolant loops that dump the heat somewhere else (or heat your insulated fish pool) shouldn't be that hard. It's basically only slightly used energy, you will find a use for it...
People who lives in meltable houses need to worry about heat ;-)
In a more serious vein (of underground water) coolant loops and piping can get expensive.  You can simply dump melted water into the atmosphere, where it will sublimate nicely enough.  Should just need a fairly small pool.  but you can't cool your ice house with liquid water, since it is necessarily hotter than the ice.  You would need to use salt water (brine), or a glycol.  then you will be using salt and recycling it, which can get intensive on a large scale.
Or you can use large arrays of piping, but large arrays of piping are extremely expensive, just talk to geothermal heat pump vendors...

You can dump a lot of heat into ice that is at -50C without melting it. Well, I'm still at the glacier idea and not at ice domes of course... If you have enough water, you can even use sublimation cooling as the Apollo suits used on the Moon. And what you need to cool is not the house, but either the air in it or the equipment and all of this will necessarily be above the freezing point of water. The ice will need to be insulated anyway.

And whatever you do, thermal management will be a thing you have to care for, but this much easier on Mars than in space where you can only radiate heat away or evaporate water (which you will have only a very limited supply of).

Offline lamontagne

  • Full Member
  • ****
  • Posts: 857
  • Liked: 1035
  • Likes Given: 198
Re: Envisioning Amazing Martian Habitats
« Reply #21 on: 10/12/2016 03:26 PM »
I find this thread would be more fun and Amazing if we thought and planed for the larger scale installations required for 1 million colonists.

We could skip the first 20 years, that are probably going to be systems that are prefabricated and come from Earth, and think about the longer term, large scale infrastructures?

-Can you fit one million people and their food production systems in a glacier?  How long will the heat sink last?
-How far away can resources be?
-What is the energy required?
-How large will the spaceport be?
-What will be the ground level infrastructures?
-What is a good size for a community in the Mars environment?


Offline Ludus

  • Full Member
  • ****
  • Posts: 663
  • Liked: 221
  • Likes Given: 94
Re: Envisioning Amazing Martian Habitats
« Reply #22 on: 10/12/2016 04:44 PM »
It really depends on where on Mars the base is and what the local resources and circumstances are.

For Hellas basin glaciers covered in a few meters of Regolith, assuming it's a relatively pure water ice glacier, maybe designs that consume the ice of the glacier, taking advantage of the thicker atmosphere in the Hellas basin. As the ice is consumed for ISRU propellant, oxygen and water, the void created might be living space. The regolith cap might be held in place both by mixing with water and freezing it and building support structure.

There's room for very large underground spaces to be hollowed out since the glaciers are hundreds of meters thick and cover square kilometers. The roof over the space would be controlled architecture using regolith rather than depending on something like lava tubes natural roof. Since the roof is designed it could be strong enough to support suspended structures hanging from it.

The space would grow as a side effect of consuming the ice anyway so the main design decision would be what shape to make the cavity.

I picture a growing vertical space that gets to be over 300m deep before hitting rock. There might be a truss structure on the surface to allow suspending structures in the space. Eventually you could have a huge 3D space with structures coming up from the floor, suspended from the roof and built into the rock walls of the cavity.

At Mars gravity with sea level air pressure flight is very easy so a main mode of transport in the space is flying. There are light airy buildings with 100 levels and lots of open balconies (that people can fly to) looking out on a vast 3D cityscape. Lower gravity, suspension from the roof and materials like carbon fiber allow pretty amazing architectural expression not seen on earth. You take an elevator to the floor which is parklike and includes lakes or the Mars surface above which is mostly industrial and utilitarian.

No idea how stable the glacier is or how much it flows. I'm assuming there's a site where there's a buried Glacier that's pretty static by earth standards. The low gravity and lack of new snowfall ought to promote stability.

I think any civilization on Mars depends on plentiful energy. Hellas is near the equator so good for solar. I think nuclear is needed anyway.

I think the best middle term chance at building pleasant environments on Mars is with large open underground spaces that permit O'Neill colony like landscapes with trees and open water. Building within the voids creating by mining glaciers in Hellas might permit this with decent intermediate designs, in a space that's being created anyway and a location that has many advantages.

If residents like the idea of natural sunlight, it can be collected on the surface and piped in. The roof isn't very thick and it's not difficult. The roof is sufficient though to protect against radiation.

A single glacier in the Hellas basin could easily hold a city of million people in this mode. At some point it would start piping in water from other nearby glaciers and starting suburbs.

I'm assuming that agriculture is just another industrial activity and is done in completely controlled environments with artificial light and works just as well in vertical stacks 300 meters high underground as anywhere.
« Last Edit: 10/12/2016 05:29 PM by Ludus »

Offline uhuznaa

  • Full Member
  • *
  • Posts: 104
  • Liked: 57
  • Likes Given: 8
Re: Envisioning Amazing Martian Habitats
« Reply #23 on: 10/12/2016 05:58 PM »
I find this thread would be more fun and Amazing if we thought and planed for the larger scale installations required for 1 million colonists.

We could skip the first 20 years, that are probably going to be systems that are prefabricated and come from Earth, and think about the longer term, large scale infrastructures?

-Can you fit one million people and their food production systems in a glacier?  How long will the heat sink last?
-How far away can resources be?
-What is the energy required?
-How large will the spaceport be?
-What will be the ground level infrastructures?
-What is a good size for a community in the Mars environment?

I think a million people would require at some point digging into rock, since you will need the water for other things. It would probably be a good idea to start at a place where you can spread out to other glaciers at least for producing fuel.

Energy will be tight, nuclear power would be necessary at least to buffer solar power problems from global sand storms that you'll be guaranteed to run into at some point. You solar power farms probably would be big enough to be seen from orbit ;-)

Going underground (either ice or rock) in the long run is inevitable, not only for radiation shielding but also for protection against landing and launching (and sooner or later crashing) spacecraft. I would expect very little ground-level infrastructure. Transportation may work for water (you will need thousands of tons to fuel a single ship), maybe buried and insulated pipelines. You could put some distance between your spaceport and ISRU facilities and the actual city, although transporting people and cargo over ground would be a major PITA. Expect many tunnels. Prospecting for iron for heavy machinery would have quite high priority I guess.

Managing your thermal and energy budgets wisely would be crucial, especially as both depend on each other: Any heat you have to reject by basically heating the ground, air or sky (by radiating it away) is wasted energy. Trying to do things as efficient as possible would be much more important than down here on Earth. I'm sure though that this would be easier with a million people than with a dozen (relatively, not absolutely).

You'd probably wise to simulate things beforehand, so you don't realize you've started it wrong too late...

At a million people population density would be high or you would need to spread out very far.

In situ research to find the best place before even starting is important. Even the first crews though have to start out where the water is or they and their ship will never make it back.

All of this would be a major undertaking, the biggest in the history of mankind. And building the spacecrafts would be just the feeble beginnings.

But even now you will find that people roughly fall into two groups: The first says "Why? I just want to sit on my couch, leave me alone, you're crazy!" and the second says "Hey, let's start! What do I have to do?". But I think anyway that not having anything to do is the curse of modernity...

Online b0objunior

  • Member
  • Posts: 83
  • Liked: 20
  • Likes Given: 0
Re: Envisioning Amazing Martian Habitats
« Reply #24 on: 10/12/2016 06:20 PM »
It really depends on where on Mars the base is and what the local resources and circumstances are.

For Hellas basin glaciers covered in a few meters of Regolith, assuming it's a relatively pure water ice glacier, maybe designs that consume the ice of the glacier, taking advantage of the thicker atmosphere in the Hellas basin. As the ice is consumed for ISRU propellant, oxygen and water, the void created might be living space. The regolith cap might be held in place both by mixing with water and freezing it and building support structure.

There's room for very large underground spaces to be hollowed out since the glaciers are hundreds of meters thick and cover square kilometers. The roof over the space would be controlled architecture using regolith rather than depending on something like lava tubes natural roof. Since the roof is designed it could be strong enough to support suspended structures hanging from it.

The space would grow as a side effect of consuming the ice anyway so the main design decision would be what shape to make the cavity.

I picture a growing vertical space that gets to be over 300m deep before hitting rock. There might be a truss structure on the surface to allow suspending structures in the space. Eventually you could have a huge 3D space with structures coming up from the floor, suspended from the roof and built into the rock walls of the cavity.

At Mars gravity with sea level air pressure flight is very easy so a main mode of transport in the space is flying. There are light airy buildings with 100 levels and lots of open balconies (that people can fly to) looking out on a vast 3D cityscape. Lower gravity, suspension from the roof and materials like carbon fiber allow pretty amazing architectural expression not seen on earth. You take an elevator to the floor which is parklike and includes lakes or the Mars surface above which is mostly industrial and utilitarian.

No idea how stable the glacier is or how much it flows. I'm assuming there's a site where there's a buried Glacier that's pretty static by earth standards. The low gravity and lack of new snowfall ought to promote stability.

I think any civilization on Mars depends on plentiful energy. Hellas is near the equator so good for solar. I think nuclear is needed anyway.

I think the best middle term chance at building pleasant environments on Mars is with large open underground spaces that permit O'Neill colony like landscapes with trees and open water. Building within the voids creating by mining glaciers in Hellas might permit this with decent intermediate designs, in a space that's being created anyway and a location that has many advantages.

If residents like the idea of natural sunlight, it can be collected on the surface and piped in. The roof isn't very thick and it's not difficult. The roof is sufficient though to protect against radiation.

A single glacier in the Hellas basin could easily hold a city of million people in this mode. At some point it would start piping in water from other nearby glaciers and starting suburbs.

I'm assuming that agriculture is just another industrial activity and is done in completely controlled environments with artificial light and works just as well in vertical stacks 300 meters high underground as anywhere.
There's a third group of people, the ones that think Mars is not the solution.

Offline RoboGoofers

  • Full Member
  • *
  • Posts: 153
  • NJ
  • Liked: 61
  • Likes Given: 133
Re: Envisioning Amazing Martian Habitats
« Reply #25 on: 10/12/2016 06:32 PM »
Somewhat jokingly: what common things would have to be reevaluated considering Mars Gravity? Earth stairs would probably be awkward. Sinks would have to be wider or deeper to catch splashing water. Walking with a cup full of water might be messy as it sloshes over the brim.

It might be impossible to assume what will work beforehand, and a comfortable solution will only be found after people get there.
« Last Edit: 10/12/2016 06:36 PM by RoboGoofers »

Offline uhuznaa

  • Full Member
  • *
  • Posts: 104
  • Liked: 57
  • Likes Given: 8
Re: Envisioning Amazing Martian Habitats
« Reply #26 on: 10/12/2016 08:08 PM »
There's a third group of people, the ones that think Mars is not the solution.

Of course Mars isn't a solution. Mars is an interesting problem.
« Last Edit: 10/12/2016 08:08 PM by uhuznaa »

Offline Impaler

  • Full Member
  • ****
  • Posts: 1283
  • South Hill, Virgina
  • Liked: 362
  • Likes Given: 0
Re: Envisioning Amazing Martian Habitats
« Reply #27 on: 10/12/2016 08:32 PM »
None of the flaws in the ice house or any other ice based structure such as inside a glacier have been addressed, the living space inside is simply uncomfortable and high maintenance on par with living in an arctic region, if your going to go to the trouble of making an enclosed space with breathable air and temperatures still substantially above the outside temperature it makes little sense to not go all the way and go to a comfortable indoor temperature.

If people want to speculate about million inhabitant level construction methods then I will give you my take.  It will consist of an arcade https://en.wikipedia.org/wiki/Arcade_(architecture) of columns and groin-vaults several stories tall and covering the ground in all directions as it grows at the edges with the first meter or two of regolith on the ground being used to make each addition.  The column interiors are regolith as is a covering over the top of all the vaults for radiation protection.  Some form of plastic, carbon-fiber or basalt fiber made from local materials is jacketed around the column to give it tensile strength and forms the vaulting as well.  Between the columns of the arcade a lattice works connect to the columns and form floor joists onto which thin bubble pressure vessels are inflated and connected to each other.  Heavy systems like liquid storage is at ground level and some kind of light-rail tram system provides horizontal transport while elevators and stairs provide vertical transport.

Offline nacnud

  • Extreme Veteran
  • Full Member
  • ****
  • Posts: 1761
  • Liked: 101
  • Likes Given: 83
Re: Envisioning Amazing Martian Habitats
« Reply #28 on: 10/12/2016 09:17 PM »
I don't think there is any problems with the low temperatures on the 'shed' part of the ice house. The conditions inside that part are much better than outside. You have

* Pressure, enough not to need a pressure suit
* Breathable atmosphere
* Protection from radiation

It gives a usable space for very little landed mass.

Inside that space you have a second chamber, lets call it a 'conservatory', which is insulated with aerogel on the inner surface of the ice so to can be warmed to 20C. This be used to grow plants and as space to hang out.

Inside that you have the landed aluminium hab with all the ECLSS etc.

Unless there is some big flaw that I'm missing it seems you get a much bigger hab for very little extra landed mass.


« Last Edit: 10/12/2016 09:18 PM by nacnud »

Offline uhuznaa

  • Full Member
  • *
  • Posts: 104
  • Liked: 57
  • Likes Given: 8
Re: Envisioning Amazing Martian Habitats
« Reply #29 on: 10/12/2016 09:38 PM »
None of the flaws in the ice house or any other ice based structure such as inside a glacier have been addressed, the living space inside is simply uncomfortable and high maintenance on par with living in an arctic region, if your going to go to the trouble of making an enclosed space with breathable air and temperatures still substantially above the outside temperature it makes little sense to not go all the way and go to a comfortable indoor temperature.

If people want to speculate about million inhabitant level construction methods then I will give you my take.  It will consist of an arcade https://en.wikipedia.org/wiki/Arcade_(architecture) of columns and groin-vaults several stories tall and covering the ground in all directions as it grows at the edges with the first meter or two of regolith on the ground being used to make each addition.  The column interiors are regolith as is a covering over the top of all the vaults for radiation protection.  Some form of plastic, carbon-fiber or basalt fiber made from local materials is jacketed around the column to give it tensile strength and forms the vaulting as well.  Between the columns of the arcade a lattice works connect to the columns and form floor joists onto which thin bubble pressure vessels are inflated and connected to each other.  Heavy systems like liquid storage is at ground level and some kind of light-rail tram system provides horizontal transport while elevators and stairs provide vertical transport.

Nobody is saying that habitats in ice would need to be cold. Insulating walls really isn't rocket science, even your deep freezer manages this. My house has snow on the roof in the winter without being cold inside. Polyethylene can be synthesized from hydrogen and carbon, you wouldn't even have to bring it.

Building big pressure vessels is HARD. Really. Drilling into rock or melting into ice gives you the big advantage of not having to build pressure vessels because you have all the weight of the ice or rock on top to counter the pressure. This weight comes for free, it's already there.

And with "pressure" I mean 10 tons for every square meter of your arcade trying to rip it apart from the inside. The tension the walls have to keep up against goes up proportionally with the radius of the vessel. Plastic just isn't going to work, you'll need aluminum or steel or carbon fibre, and lots of it. And you will have to build it as a sphere or a cylinder, because it will pop out immediately otherwise. And the smallest weakness somewhere can make it fail catastrophically.

And you will still have to insulate it, because the regolith on top and beneath and with it the skin of your building will be at the same temperature as the ice in a glacier.

Offline renclod

  • Extreme Veteran
  • Full Member
  • ****
  • Posts: 1663
  • EU.Ro
  • Liked: 8
  • Likes Given: 2
Re: Envisioning Amazing Martian Habitats
« Reply #30 on: 10/12/2016 09:49 PM »
Most people crazy enough to leave Earth for Mars will treasure mobility above all else, probably. They will hate to be pinned down for long whiles. They will work on building large rovers and then move to another site.  They will build robots, start them on a site task and then move on.  Airlocks will be plenty and large mobile habs likewise, probably. For a century at least.

Offline Lumina

Re: Envisioning Amazing Martian Habitats
« Reply #31 on: 10/13/2016 12:20 AM »
(Reposting from general discussion thread)

Here's my vision for amazing habitats on Mars. I imagine networks of cliffside cities with many panoramic windows dug out from mesas, natural canyon walls or even Tatooine-style dugouts, featuring:
 
- multiple levels,
- dozens of windows and dome-covered verandas with panoramic views,
- excellent protection from radiation,
- robustly stable indoor temperatures, so one less thing that can go wrong,
- shirtsleeve access via tunnels to surface facilities above or nearby (e.g. power generation, greenhouses, landing pads),
- redundant protection from decompression with segments protected by automatic airlocks,
- grand and inspiring elaborate carved entrances with inspiration from all ancient cultures on Earth,
- direct shirtsleeve access (via tunnels / airlocks) to mines for resource extraction

Besides excavation equipment and the usual internal equipment needed for habitats, the following will be needed:

- a scalable and flexible solution for a flooring and false ceiling system that can eventually use in situ resources,
- a scalable solution for sealing excavated tunnel surfaces that can also eventually use in situ resources (some kind of epoxy?),
- automatic airlocks and door systems to separate segments for safety,
- a modular system to create windows or external domes to cover "verandas", also evolvable to use in situ resources for the future.

Offline Ludus

  • Full Member
  • ****
  • Posts: 663
  • Liked: 221
  • Likes Given: 94
Re: Envisioning Amazing Martian Habitats
« Reply #32 on: 10/13/2016 06:23 AM »
None of the flaws in the ice house or any other ice based structure such as inside a glacier have been addressed, the living space inside is simply uncomfortable and high maintenance on par with living in an arctic region, if your going to go to the trouble of making an enclosed space with breathable air and temperatures still substantially above the outside temperature it makes little sense to not go all the way and go to a comfortable indoor temperature.

If people want to speculate about million inhabitant level construction methods then I will give you my take.  It will consist of an arcade https://en.wikipedia.org/wiki/Arcade_(architecture) of columns and groin-vaults several stories tall and covering the ground in all directions as it grows at the edges with the first meter or two of regolith on the ground being used to make each addition.  The column interiors are regolith as is a covering over the top of all the vaults for radiation protection.  Some form of plastic, carbon-fiber or basalt fiber made from local materials is jacketed around the column to give it tensile strength and forms the vaulting as well.  Between the columns of the arcade a lattice works connect to the columns and form floor joists onto which thin bubble pressure vessels are inflated and connected to each other.  Heavy systems like liquid storage is at ground level and some kind of light-rail tram system provides horizontal transport while elevators and stairs provide vertical transport.

I agree with most of your critique of the ice house. None of those things apply to occupying space inside a glacier. You need to insulate the ice face, but there's no reason the temperature in the space opened up inside the glacier can't be like Hawaii. If you start at the edge where the glacier meets rock and expose it as you consume the ice going down, you can build into the rock or attach to it as well as suspend structures from the roof.

I don't think any sort of surface structure can provide a pleasant or safe city environment on Mars. That requires very large open spaces with normal atmosphere and as you suggest pleasant temperatures. It all has to be shielded from surface conditions and permit construction in an earthlike "outdoor" environment.

If you build anything on the surface it has to be a separate pressure vessel. It's just incredibly wasteful of materials and effort to build tiny volumes of habitable space on the surface when you are creating a huge habitable volume that can be very efficiently pressurized as a side effect of consuming the glacier anyway. The image of ice near you suggests cold but there's no real issue with the void in the glacier being cold. The ice face just has to be insulated to protect it from the waste heat of the settlement. Unlike the icehouse design nothing is built out of ice.

Offline guckyfan

  • Senior Member
  • *****
  • Posts: 6025
  • Germany
  • Liked: 1483
  • Likes Given: 1209
Re: Envisioning Amazing Martian Habitats
« Reply #33 on: 10/13/2016 06:30 AM »
Inside that space you have a second chamber, lets call it a 'conservatory', which is insulated with aerogel on the inner surface of the ice so to can be warmed to 20C. This be used to grow plants and as space to hang out.

Growing plants inside that ice house would require tremendous energy for lighting. It would be very hard to keep temperatures low enough to not melt the ice dome. Not impossible but for greenhouses I think there would be better solutions. The plants don't need radiaton protection.


Offline Ludus

  • Full Member
  • ****
  • Posts: 663
  • Liked: 221
  • Likes Given: 94
Re: Envisioning Amazing Martian Habitats
« Reply #34 on: 10/13/2016 06:32 AM »
(Reposting from general discussion thread)

Here's my vision for amazing habitats on Mars. I imagine networks of cliffside cities with many panoramic windows dug out from mesas, natural canyon walls or even Tatooine-style dugouts, featuring:
 
- multiple levels,
- dozens of windows and dome-covered verandas with panoramic views,
- excellent protection from radiation,
- robustly stable indoor temperatures, so one less thing that can go wrong,
- shirtsleeve access via tunnels to surface facilities above or nearby (e.g. power generation, greenhouses, landing pads),
- redundant protection from decompression with segments protected by automatic airlocks,
- grand and inspiring elaborate carved entrances with inspiration from all ancient cultures on Earth,
- direct shirtsleeve access (via tunnels / airlocks) to mines for resource extraction

Besides excavation equipment and the usual internal equipment needed for habitats, the following will be needed:

- a scalable and flexible solution for a flooring and false ceiling system that can eventually use in situ resources,
- a scalable solution for sealing excavated tunnel surfaces that can also eventually use in situ resources (some kind of epoxy?),
- automatic airlocks and door systems to separate segments for safety,
- a modular system to create windows or external domes to cover "verandas", also evolvable to use in situ resources for the future.

If you start at the edge of the glacier where it meets rock and expose the rock face as you consume the glacier you can attach to or build into the rock as well as suspend structures from the roof. The process of using the ice opens up space for this sort of thing in a volume that can have a comfortable atmosphere.

Offline guckyfan

  • Senior Member
  • *****
  • Posts: 6025
  • Germany
  • Liked: 1483
  • Likes Given: 1209
Re: Envisioning Amazing Martian Habitats
« Reply #35 on: 10/13/2016 06:33 AM »
Moving my post from the IAC thread here.

Glaciers may move on Mars but sure at a much slower rate. The ice is much colder and harder. Also forces moving them are smaller. On earth glaciers move because they are on a slope or because there is new precipitation which produces thrust. Both would be absent or much smaller on Mars.

Habitats could be well insulated houses. The caves in the glacier could be very large so heat from the habitats can dissipate into the glacier without causing melting. The caves would be pressurized so people could be outside without spacesuit though they would need heavy arctic clothing. If temperatures could be kept at -10-15C and the air dry, being outside could be even fun with little air movement. This would likely not be the only type of habitat but it could be one option.

I have visited a salt mine with huge caves. That should look somewhat similar and it was gorgeous.

Offline guckyfan

  • Senior Member
  • *****
  • Posts: 6025
  • Germany
  • Liked: 1483
  • Likes Given: 1209
Re: Envisioning Amazing Martian Habitats
« Reply #36 on: 10/13/2016 06:46 AM »
Another concept that could give wide open spaces though with columns.

Place columns made of Marscrete, reenforced with basalt fibre and space them equally in a hexagonal pattern. Build prefab hexagonal domes to place them on top of the columns. Place a regolith cover on top of the domes heavy enough to counteract pressurization. That's heavy and the columns need to be strong enough to support them. The structure should be strong enough to stand up when one column fails and needs to be replaced. That pattern can be extended gradually.

The structure would need safety features in case of breaches. It should have sections that can be sealed off. They should also have small pressurized shelters and maintain pressure when breached long enough for people to reach those shelters.

The advantage would be a large connected area where people can roam without pressure suits.

Offline Ludus

  • Full Member
  • ****
  • Posts: 663
  • Liked: 221
  • Likes Given: 94
Re: Envisioning Amazing Martian Habitats
« Reply #37 on: 10/13/2016 06:58 AM »
None of the flaws in the ice house or any other ice based structure such as inside a glacier have been addressed, the living space inside is simply uncomfortable and high maintenance on par with living in an arctic region, if your going to go to the trouble of making an enclosed space with breathable air and temperatures still substantially above the outside temperature it makes little sense to not go all the way and go to a comfortable indoor temperature.

If people want to speculate about million inhabitant level construction methods then I will give you my take.  It will consist of an arcade https://en.wikipedia.org/wiki/Arcade_(architecture) of columns and groin-vaults several stories tall and covering the ground in all directions as it grows at the edges with the first meter or two of regolith on the ground being used to make each addition.  The column interiors are regolith as is a covering over the top of all the vaults for radiation protection.  Some form of plastic, carbon-fiber or basalt fiber made from local materials is jacketed around the column to give it tensile strength and forms the vaulting as well.  Between the columns of the arcade a lattice works connect to the columns and form floor joists onto which thin bubble pressure vessels are inflated and connected to each other.  Heavy systems like liquid storage is at ground level and some kind of light-rail tram system provides horizontal transport while elevators and stairs provide vertical transport.

Nobody is saying that habitats in ice would need to be cold. Insulating walls really isn't rocket science, even your deep freezer manages this. My house has snow on the roof in the winter without being cold inside. Polyethylene can be synthesized from hydrogen and carbon, you wouldn't even have to bring it.

Building big pressure vessels is HARD. Really. Drilling into rock or melting into ice gives you the big advantage of not having to build pressure vessels because you have all the weight of the ice or rock on top to counter the pressure. This weight comes for free, it's already there.

And with "pressure" I mean 10 tons for every square meter of your arcade trying to rip it apart from the inside. The tension the walls have to keep up against goes up proportionally with the radius of the vessel. Plastic just isn't going to work, you'll need aluminum or steel or carbon fibre, and lots of it. And you will have to build it as a sphere or a cylinder, because it will pop out immediately otherwise. And the smallest weakness somewhere can make it fail catastrophically.

And you will still have to insulate it, because the regolith on top and beneath and with it the skin of your building will be at the same temperature as the ice in a glacier.

...and any "buildings" you build on the surface have these issues that have to be addressed for each structure separately. Each ends up enclosing a tiny habitable volume at great expense. Meanwhile you have to consume vast amounts of ice in the glacier just for propellant and basics leaving a huge and growing volume that's comparatively cheap and easy to pressurize and make comfortable. That space is a resource unique to this sort of location.





Offline Ludus

  • Full Member
  • ****
  • Posts: 663
  • Liked: 221
  • Likes Given: 94
Re: Envisioning Amazing Martian Habitats
« Reply #38 on: 10/13/2016 07:11 AM »
Moving my post from the IAC thread here.

Glaciers may move on Mars but sure at a much slower rate. The ice is much colder and harder. Also forces moving them are smaller. On earth glaciers move because they are on a slope or because there is new precipitation which produces thrust. Both would be absent or much smaller on Mars.

Habitats could be well insulated houses. The caves in the glacier could be very large so heat from the habitats can dissipate into the glacier without causing melting. The caves would be pressurized so people could be outside without spacesuit though they would need heavy arctic clothing. If temperatures could be kept at -10-15C and the air dry, being outside could be even fun with little air movement. This would likely not be the only type of habitat but it could be one option.

I have visited a salt mine with huge caves. That should look somewhat similar and it was gorgeous.

This is what I was assuming about glaciers there. Without new snowfall or geological activity I'd think they'd be much slower (though it's clear from the pictures that they flow, it may not be on a human relevant timescale). I'd have to think that insulating the face of the ice from the settlement's air temperature isn't that killer an issue. A settlement with reactors and waste heat anyway could keep a huge volume at a very comfortable temperature. Reactors could be located in the rock a short distance away.

Offline guckyfan

  • Senior Member
  • *****
  • Posts: 6025
  • Germany
  • Liked: 1483
  • Likes Given: 1209
Re: Envisioning Amazing Martian Habitats
« Reply #39 on: 10/13/2016 07:31 AM »

 I'd have to think that insulating the face of the ice from the settlement's air temperature isn't that killer an issue. A settlement with reactors and waste heat anyway could keep a huge volume at a very comfortable temperature. Reactors could be located in the rock a short distance away.

Keeping the habitats warm is not what I am concerned about. Dumping waste heat while making sure the ice won't melt is the engineering challenge IMO. That would require the ice surface to be exposed and temperatures well below freezing. People do enjoy winter temperatures and snow and ice. Though some caves may be isolated and kept warm so plants can grow.

Technical solutions to dissipate low temperature heat energy would be complex and may be prone to failure. Better to have a naturally stable system.

Having some green to walk throug is nice to have. But light for plants would introduce a lot of heat that needs to be dissipated. I am not thinking of growing much food there but plants that need little light as a public park. Plants like ferns and philodendron. Plus a few separately lighted spots for plants that grow fruit like strawberries.

Tags: