SpaceX Mars City Buildings / Plan

[YNM]

1 minute ago, tater said:

Here in NM, traditional houses have walls about a meter thick. You can have quite large windows that have no lateral view at all once you're a step or two to the side.

Anyway, I think it is entirely possible to make real window openings that mitigate exposure. Just don't put beds next to them, lol.

Yeah, honestly I'd only check windows if I want to see what it's like outside too.

[tater]

28 minutes ago, YNM said:

Yeah, honestly I'd only check windows if I want to see what it's like outside too.

I think that the idea of public spaces where people can have a sense of where they are is pretty important. Bars, restaurants, whatever.

Even with views at home, you notice them only at certain times for most people. I am probably pretty spoiled in that regard, we have frankly spectacular views. In my old house, the view outside was to the street on two sides, a narrow space between ours and the next house on another (only high windows for light/ventilation on that side), and to the back yard on the last side. The back yard was the real "view," and that sort of view could be done inside on Mars. Have internal green parklike areas, and residences have views to them. I have lived in the current house for almost 20 years now, and now I notice the outside rather a lot. I can see a peak below me out the window behind this computer that is ~145 km away (just dragged a ruler on google earth to check, lol).

(edit: it's a ~3300m peak, but is slightly below level LOS due to curvature of the Earth even though I'm at closer to 1900m alt)

Edited February 26, 2021 by tater

[kerbiloid]

And again should we respectfully refer to the historical stuff.

(Except the big "gothic" buildings)

Caponier

Spoiler

Look at these skewed window openings.

The caponier protects you from fire galactic and solar radiation from front with a thick wall, but allows to shoot look along the wall at the opponent's flank Martian sunset.

And now look inside.

Spoiler

The thick internal wall ledges/bulges absorb the solar radiation to prevent the room irradiation from flanks.

So, until you get to th window to look outside to ensure that nobody has stolen your precious piece of useless lifeless wasteland, you are under the wall protection and still have a feeling that you are not encased in the safe, reliable bunker, but somebody has opened the windows to the amazing new world (-100°C, 0.001 bar).

When you come to the window, you can look outside through the window.

Similar scheme in medieval fortress towers.

[YNM]

3 hours ago, tater said:

I think that the idea of public spaces where people can have a sense of where they are is pretty important. Bars, restaurants, whatever.

idk, over here most of those are in malls, other times it's just simply a view of where I am. Here it's very lush so what you tend to see is just dense trees anyway, either that or dense houses but that's more on the housing areas. From where I live on the second floor your view is houses with trees sticking out here and there.

3 hours ago, tater said:

The back yard was the real "view," and that sort of view could be done inside on Mars. Have internal green parklike areas, and residences have views to them.

Hmm... EPCOT ? (as Walt Disney envisioned it)

2 hours ago, kerbiloid said:

And now look inside.

That's just natural lighting.

 

That being said, even if outside views might prove difficult, I think natural lighting on Mars, even if it's somewhat dim, would be appreciable compared to continuous artificial lighting, even if it's not as bright as here on Earth... Maybe we could incorporate something like this light tube thing ? It's basically bottle filled with water.

[kerbiloid]

47 minutes ago, YNM said:

That's just natural lighting.

Yes. Isn't that the intention?

[YNM]

39 minutes ago, kerbiloid said:

Yes. Isn't that the intention?

idk but for "windows" I want more than merely natural lighting. Plus you can use light pipes or something instead where it can be filled with water or just made out of clear acrylic.

[kerbiloid]

20 minutes ago, YNM said:

idk but for "windows" I want more than merely natural lighting.

It's a simple window but in skewed direction, what can be more natural?

[YNM]

1 minute ago, kerbiloid said:

It's a simple window but in skewed direction, what can be more natural?

... alright, I guess the image you put there was with the lighting on on the inside ?

[kerbiloid]

4 minutes ago, YNM said:

... alright, I guess the image you put there was with the lighting on on the inside ?

Just a daylight through the windows.

[tater]

Light pipes are clearly a good idea, I have some of those as well:

 

Highly reflective tubes, and they can deliver light several meters from the roof penetration.

I was specifically concerned with views. Looking outside, and seeing... something, the terrain, etc.

 

For clarity on view (my overhangs are probably smaller than I thought, maybe 35-40cm), my windows are high on the wall (literally against ceiling), so the relative viewer position really matters. If closer to eye level, then  the sky view would require lowering head position.

Spoiler

~3.5-4m from window (behind bush is just hill and mountain):

 

~1.5m from window:

An interior like this:

Need not require that above that dome is SKY, the light could be directed by light pipes through whatever roofing is actually required, perhaps supplemented by artificial light.

 

A space like the bar below could have the upper window gone (light pipe, instead), and an overhang mitigating much of the radiation from the sky direction. The seating could also be set into the room from the window, with a planter where the window booths are. People would experience the view , and only a sliver of sky.

 

Edited February 26, 2021 by tater

[mrfox]

Its fun and exciting to imagine what these fancy futuristic habs migh look like - but what would be the tech readiness level of these designs? 

Realistically, and for the forseeable future - the overriding structural consideration for these habs will be the pressure vessel. So the design of these habs will be similar to an underwater hab.

Like this

https://en.wikipedia.org/wiki/Helgoland_Habitat

https://en.wikipedia.org/wiki/Tektite_habitat

Skylights and panoramic  windows makes as much sense here as they do on an airplane or submarine. Think portholes.

[tater]

7 minutes ago, mrfox said:

Skylights and panoramic  windows makes as much sense here as they do on an airplane or submarine. Think portholes.

Aircraft? Sure, sorta. Subs? No. Vastly higher forces on a submarine.

Holding 1 atm is not a huge constraint, particularly when it is stationary. Nothing will break them, there is no wind loading, etc. No hail, no bird impacts.

 

[mrfox]

Its not simply material strength. You have to consider the load paths of whats holding the rest of the structure together. A large window is a large structural void, with its associated stress concentrations. More importantly there are also failure mode considerations. Part of aircraft window sizing specifications involves consideration in the case of a window blowout. On aircraft, it is related to how quickly it can descent to a safe altitude. On a Mars hab - it would be how quickly a compartment can be evacuated or emergency equipment be activated vs how long the space can be kept partially pressurised.

You can’t design a safety critical structure based on the premises that “nothing will break them”.

[tater]

20 minutes ago, mrfox said:

Its not simply material strength. You have to consider the load paths of whats holding the rest of the structure together. A large window is a large structural void, with its associated stress concentrations. More importantly there are also failure mode considerations. Part of aircraft window sizing specifications involves consideration in the case of a window blowout. On aircraft, it is related to how quickly it can descent to a safe altitude. On a Mars hab - it would be how quickly a compartment can be evacuated or emergency equipment be activated vs how long the space can be kept partially pressurised.

You can’t design a safety critical structure based on the premises that “nothing will break them”.

No, but the loads are less than here (0.38g), so I don't think the static loads are daunting.

Nothing natural will break them to be more clear. Humans? Yeah, if the building is poorly designed, maybe a truck drives into the window. Any windows that face landing areas? They need a plan B, obviously.

Holding in 1 atm is not a big deal.

Because of the safety issue vs terrestrial windows, the standards will obviously be higher. Laminated glass, certainly.

This is an interesting idea for people who have to live under ground:

Outside of the room is an aquarium. They can raise fish for people to eat, and the light can be piped in with a heliostat.

 

[mrfox]

It certainly is “possible”. I mean there are airplanes and submarines out there with bubble canopies. The question is, whats the tradeoff, and is it worth it?

Its like the old engineering proverb -

A scientist will ask whether it is possible.

Marketing will ask what it can be used for. 

Accounting will ask how much it will cost.

and engineering will ask whether its worth the effort to build.

Your underwater restaurant is the perfect example - how many have been built? And how much does it cost to dine there? 

[tater]

26 minutes ago, mrfox said:

It certainly is “possible”. I mean there are airplanes and submarines out there with bubble canopies. The question is, whats the tradeoff, and is it worth it?

If I was stuck on Mars for the rest of my life, um, yeah, it's worth it. I want to see outside.

 

26 minutes ago, mrfox said:

Its like the old engineering proverb -

A scientist will ask whether it is possible.

Marketing will ask what it can be used for. 

Accounting will ask how much it will cost.

and engineering will ask whether its worth the effort to build.

Why would windows not be worth it?

Literally every design in the NASA contest for 3D printed habs has windows. Not just light pipes to save power, windows, to look out.

Windows are a source of heating and cooling issues in the overwhelming majority of houses (unless you live in an earth ship or something similar)—but I assume you have not walled in all your windows as not worth the lost heat in the winter, and cooling problems in the summer, right?

What is the psychological cost of being trapped inside all the time? I maintain "non-zero."

I'm not a fan of Mars colonization, but if you are going to consider it, it needs to be someplace people want to live. Won't catch me moving there, I'd buy a second house in Italy instead. Pretty views, better food.

 

26 minutes ago, mrfox said:

Your underwater restaurant is the perfect example - how many have been built? And how much does it cost to dine there? 

No idea, that one is in Dubai, so I imagine a lot. That one is also under actual ocean. I used to take my kids to the restaurant next to the shark tank at our aquarium all the time. For public spaces in a city where people are forced to live underground, they will need pools of water for various reasons, and raising seafood is once of them. Throwing some cool plexiglass tubes through them seems like a cool idea (our aquarium has one of those, too), and putting some tables in and serving food, even better. Retasking facilities they need anyway to also improve psychological wellbeing seems a no-brainer. Hydroponics might be most efficient for most of their food needs, but some areas with crops growing in a way that people can walk among them in a more naturalistic way, or look out across them as a view from their apartments seems to make sense to me. If large water tanks are needed, then make them also serve as decorative features.

[mrfox]

 

2 hours ago, mrfox said:

A scientist will ask whether it is possible.

Marketing will ask what it can be used for. 

Accounting will ask how much it will cost.

and engineering will ask whether its worth the effort to build.

Forgot the last and most important line -

“Finally, the CEO will ask - can we afford to do it?” (Or not do it, in this case)

2 hours ago, tater said:

If I was stuck on Mars for the rest of my life, um, yeah, it's worth it. I want to see outside.

Why would windows not be worth it?

Because we will likely have limited resources. And there will be so many priorities ahead of “a pretty but expensive view”.

2 hours ago, tater said:

Windows are a source of heating and cooling issues in the overwhelming majority of houses (unless you live in an earth ship or something similar)—but I assume you have not walled in all your windows as not worth the lost heat in the winter, and cooling problems in the summer, right?

What is the psychological cost of being trapped inside all the time? I maintain "non-zero."

Igloos don’t have windows. And this is the level of austerity I imagine a Mars colony will be operating under using current tech. Now if we can hand-wave in some magical future tech which drastically lowers the cost of building, transporting, and erecting Mars infrastructure - in that case this is more of a sci-if then a science-tech discussion, and I defer the podium to Elon’s, yours and everyone else fancy renderings.

There are way cheaper and easier ways to provide psychological relief from enclosed spaces. The cost-benefit ratio of windows makes no sense at our current tech level. 

 

[tater]

1 hour ago, mrfox said:

 

Forgot the last and most important line -

“Finally, the CEO will ask - can we afford to do it?” (Or not do it, in this case)

Because we will likely have limited resources. And there will be so many priorities ahead of “a pretty but expensive view”.

I'll say again, I'm not a Mars colonization fanboy. I've said on this forum I think the first town should be called "New Donner."

That said, there is no CEO with such priorities, since there is no possible economic incentive to colonize Mars.

If you want people to move to Mars, you must make Mars a destination humans want to go to. All off-earth environments are 100% designed/built. The only real estate on Mars is stuff that people can walk around in naked.

So yeah, obviously the first places are gonna be bare.

Musk is right about needing a decent number of people for such a colony to survive. He throws around "1 million," but perhaps fewer still works. Probably not less than 100s of thousands, though. They must have every single discipline/trade there, and for some jobs that scale to population, more and more. If you want to attract a population of people the size if a small city to Mars, it needs to be nice. I mean, they need several of every single medical specialty. No one making a few hundred grand wants to move to live in a tube the size of their walk in closet on Earth to "colonize Mars." A few loons will go no matter how awful it is. Others will need convincing, so the "business model" needs to be to make it someplace people WANT to go to. (and good luck with that, lol)

 

Quote

Igloos don’t have windows. And this is the level of austerity I imagine a Mars colony will be operating under using current tech. Now if we can hand-wave in some magical future tech which drastically lowers the cost of building, transporting, and erecting Mars infrastructure - in that case this is more of a sci-if then a science-tech discussion, and I defer the podium to Elon’s, yours and everyone else fancy renderings.

There's a chicken and egg problem, see above. If it's not worth going to, no one goes.

As for the magical tech... the most important is being worked on, it's the transportation. They'd have to send ahead equipment to build stuff using indigenous materials. Equipment to mine and crush regolith for concrete, 3D printers to print early structures (more igloo like than shopping mall, to be sure), boring company drills? Eracting it is a job for robots/people I guess (preferably more robots).

You seem to lump me in with Elon—I'm only commenting on what I think is required if the goal is a self-sustaining colony, since the number of people is huge, and it better be NICE, else it's a few dozen people deciding who they will eat first when the resupply ships don't come.

 

Quote

There are way cheaper and easier ways to provide psychological relief from enclosed spaces. The cost-benefit ratio of windows makes no sense at our current tech level.
 

The artificial skylights I actually posted in some other Mars colony thread, they're cool. Screens? Maybe, but fairly pointless, might as well send just 1 as a TV/computer. I don't stare at live cams of cool places  instead of looking out my windows here, I wouldn't there, either.

As for tech level, laminated glass is not terribly expensive, nor terribly high tech.

Spoiler

 

 

MARSHA won the NASA contest, this was second place:

 

It's important to remember that initial bases, even "camps" for construction crews are not the final "city." If they want to build a city, they're gonna need all kinds of capability, the ability to make steel or aluminum, glass, etc., and fabricate complex parts with those basic materials as well. (and for the Nth time I don't personally find it likely, I'm just saying what they need to do)

Edited February 27, 2021 by tater

[kerbiloid]

Make the structure out of local concrete, then put pressurized modules on the floors and connect them with tubes.

3 hours ago, tater said:

What is the psychological cost of being trapped inside all the time? I maintain "non-zero."

On the Earth the windows is a look at freedom, on Mars it's a view of death.
What is a psychological cost of looking at the place which looks so comfy but would kill in seconds?
From time to time somebody will go out to take a breathe.

On the Earth there is something changing outside. Birds, cats, people, clouds, cars, trees with leaves, grass  under wind, etc.
On Mars it's a static picture with sudden dust whirls in deadly vacuum. And if there is a town, its houses should be placed so closely to each other (to keep the infrastructure compact) that actually nothing but walls.
The picture of walls and motionless wasteland can be just painted. An on-wall display is just a luxure for it.

Do Arctic/Antarctic stations have a lot of windows?
Imho, it's enough to have a windowed gallery on top and good displays on walls.
Maybe also concrete caponiers with pressurized modules inside.

It's more important to develop the internal recreational infrastructure.
Human eyes need a distance to unfocus. And this can be done with several tens meters wide gardens and atriums.

What about undersea habitats? There is always a darkness and lethal pressure outside.
The best lamps could lighten just first several meters, and even they would have fishes to look at.
 

4 hours ago, mrfox said:

Its like the old engineering proverb -

A scientist will ask whether it is possible.

Marketing will ask what it can be used for. 

Accounting will ask how much it will cost.

and engineering will ask whether its worth the effort to build.

And a designer won't ask. He will do. Others will ask him. 
What the thing has he drawn, how can such thin pillar carry the whole balcony, and why three different walls have a common corner, and how to carry 93 cm wide things through the 89 cm wide door.

45 minutes ago, tater said:

As for tech level, laminated glass is not terribly expensive, nor terribly high tech.

And hardly repairable.
And their structural integrity depends on the structural completeness (?). Unlikely they can just replace a piece of wall on those pictures, if they want to have it pressurized after the repair.
In a metal wall they could just replace a panel, or patch a hole, because the trusses carry, the envelopes keep the air.
The same wit printed habitats. Nice on Earth, maybe useful outside of it for rough external constructions, say for wloors and walls, but not for being pressurized.

[NFUN]

21 minutes ago, kerbiloid said:

Do Arctic/Antarctic stations have a lot of windows?

[YNM]

7 hours ago, mrfox said:

Its not simply material strength. You have to consider the load paths of whats holding the rest of the structure together. A large window is a large structural void, with its associated stress concentrations.

In the case of a Mars hab the load paths are closer to what you have on the ISS, ie. mostly pressure load from within the structure rather than self-gravity like on Earth buildings or external pressure like in a sub. Most of the stress you'd see are tensile ring stresses rather than compression stress. And as long as there aren't quakes on Mars the same magnitude that there are on Earth then the strengths and redundancy required are actually very low (PGA from earthquakes can exceed the 0.38g Mars gravitation so consider that an earthquake-resistant building can support itself being cantilevered from a vertical wall on Mars gravity). Probably the only cataclysmic event that could happen are either sudden depressurization, sudden overpressurization from the inside (say, if there was a conflagration and explosion inside) or overpressurization from the outside (say, the lander exploded or small meteorite impact) which are usually one-peak non-oscillating loads, which doesn't need as much redundancy and ductility as proper cyclic loads like earthquake loads back on Earth.

Edited February 27, 2021 by YNM

[mrfox]

An interesting example is the cupola module in the ISS. It took over 2 decades of inter-departmental and international squabbling to eventually get something built and sent up that was half its original design size.
 

And this is after 40 years of space station design iterations and experience - from the Salyuts, Almaz, and Skylabs, to Mir. 40 years - and 10 stations - with nothing but portholes. 
 

IMHO the cupola was lucky to have been built when it was, any further delays would’ve put it squarely against the remote video monitoring tech of today, and made its primary observational role superfluous and its risk even harder to justify. Still looks cool though.

1 hour ago, kerbiloid said:

And a designer won't ask. He will do. Others will ask him. 

A CAD monkey does as he/she is told. A “good” designer must ask and evaluate what the the risk-reward balance is worth.
Otherwise, you risk being remembered in posterity in engineering ethics textbooks as an example of what not to do.

Edited February 27, 2021 by mrfox

[tater]

I suppose given the thread title of SpaceX Mars city it would be interesting to think about what you could actually bring with Starship (assuming it works).

I'm not thinking of materials to build with, I'm thinking of bootstrapping tech. What's the lowest mass you could get the equipment to mine, then a blast furnace, etc? What about other equipment to work that metal into something useful? Drilling gear. Then smaller hab concepts like MARSHA need the stock for printing habs (and whatever gear is required to create the basalt filler).

 

6 minutes ago, mrfox said:

IMHO the cupola was lucky to have been built when it was, any further delays would’ve put it squarely against the remote video monitoring tech of today, and made its primary observational role superfluous and its risk even harder to justify. Still looks cool though.

This is heading to the ISS over the next few years:

https://www.nasa.gov/press-release/nasa-selects-first-commercial-destination-module-for-international-space-station

Kinda large windows, plus more porthole types on the other elements. Of course ISS requires a different level of safety, as there is a good chance any given bit gets clobbered with paint chips, etc at orbital velocity. Not a factor on Mars. Meteor risk exceeds risk on Earth, but as the roof of most structures will have fair bit of regolith, not really an issue, either.

The arguments against windows for a sort duration hab for sortie missions might make engineering sense, but for places where humans live, the sub-discipline is really architecture. In the (unlikely) even large numbers of humans are trying to live on Mars, how they interact with their built environment is nothing short of critical. It is not a mechanistic problem, else they could be sealed into featureless metal and plastic cells, or whatever is most "efficient."

Heck, when it comes to public spaces, they will need some really huge ones. At 0.38g, if they'd like to kick a ball around, the field size might have to increase (assuming humans don't just waste away in 0.38g, something the Mars fans should try and figure out before they leave, lol). Any such huge parks (assuming there is a good way to build stadium sized outside feeling areas) could be ringed with apartments.

There was a bizarre design contest for NY I saw once where someone dug Central park down to the bedrock, and made a sunken park, ringed on all sides with walls of "subterranean" apartments (that opened to a view of the new park). (I will drop a pic if I find one).

 

Sunken skyscraper (the wall of glass on the far side has the "roof" at street level, Central Park West:

Obviously that is too huge, but a smaller version with a roof over it could serve for Mars. The ground with mixed space for recreation, and maybe gardens (for food)... heck, even livestock.

 

[YNM]

3 hours ago, mrfox said:

An interesting example is the cupola module in the ISS. It took over 2 decades of inter-departmental and international squabbling to eventually get something built and sent up that was half its original design size.

And this is after 40 years of space station design iterations and experience - from the Salyuts, Almaz, and Skylabs, to Mir. 40 years - and 10 stations - with nothing but portholes.

IMHO the cupola was lucky to have been built when it was, any further delays would’ve put it squarely against the remote video monitoring tech of today, and made its primary observational role superfluous and its risk even harder to justify. Still looks cool though.

I think the primary concern with Cupola was with micrometeorite impact rather than with pressure. I imagine Mars surface should see somewhat less of it... Or even if it *does* get a lot of micrometeorite impacts at the very least we can limit the angles only to 'grazing' impacts. (will limit FoVs however.)

3 hours ago, mrfox said:

A CAD monkey does as he/she is told. A “good” designer must ask and evaluate what the the risk-reward balance is worth.

They're called "drafters". You'd still find them in any project.

In the past (as in, victorian era), if you want to become an engineer, you actually have to graduate up the scheme, from surveyors to drafters to engineers. Only today do we have people studying engineering from the start. I still often look up to CAD to see whether my calculations makes sense or whether they're just a garbage of numbers.

3 hours ago, tater said:

I suppose given the thread title of SpaceX Mars city it would be interesting to think about what you could actually bring with Starship (assuming it works).

I'm not thinking of materials to build with, I'm thinking of bootstrapping tech. What's the lowest mass you could get the equipment to mine, then a blast furnace, etc? What about other equipment to work that metal into something useful? Drilling gear. Then smaller hab concepts like MARSHA need the stock for printing habs (and whatever gear is required to create the basalt filler).

The first few habs (apart from the repurposed landers) would have to be inflatable I guess... Bring pressurized/liquefied oxygen and nitrogen for the first few missions, later on use sabatier reaction + electrolysis to provide oxygen although we'd still need regular supply of nitrogen and hydrogen.

Building the habs from scratch, I'm tempted to see more of a concrete/adobe thing rather than more inflatables or tin cans. Inflatables usually mean hydrocarbon which we don't have a lot of at hand. Blast furnaces (and later oxygen blowing for steelmaking) requires oxygen to work so I think that's a lot of oxygen used up just to refine iron/steel. I'm imagining more of reinforced earth structure with the reinforcement made out of sintered rock, back on Earth we have basalt rebars but idk what rock/mineral would be suitable on Mars. This is why I think underground is the way to go, you only need the "concrete" with reinforcement for lining the tunnels rather than building everything out of it. Either that or a massive inflatable dome where the inside would look like those villages from ancient times made out of mud.

Edited February 27, 2021 by YNM

[kerbiloid]

4 hours ago, tater said:

I'm thinking of bootstrapping tech. What's the lowest mass you could get the equipment to mine, then a blast furnace, etc?

Depends on the aim, obviously.

What about the food? Are they going to deliver it or to grow/herd?
(This depends on the population size. Is it enough large to need the local farming, or they will be happy if throw them a truck of frozen chickens once per year.)

Just everything starts from food processing, from its appearing to disappearing. And everything other is bound to that.

Edited February 27, 2021 by kerbiloid