# Can Mars colonies use the interior of mountains and hills rather than the surface?

I am writing a fiction about Mars, 300 yrs after colonization. Earth turns hyper-fundamental and cuts off all communication, so they've been on their own for the past two centuries. In constructing this world, I think perhaps the place to build the three redundant settlements is in the interiors of hills or mountains, rather than on the surface with all the radiation, dust storms, and very low temperatures. Is this feasible? Also, rather than the old moon-buggy or hab-lab transports, what about underground tunnels. Sound way better. Thanks

• how big are those colonies, amount of people. Sep 20 '16 at 23:23
• You mean they dig habitats underground? Why specifically hills not plains? Sep 20 '16 at 23:43
• I wouldn't dig into hills. Mars hat a lot of desert between them. Shoveling sand is far easier than breaking though volcanic rock.
– Karl
Sep 22 '16 at 2:48
• Hello Phyllis and welcome to Worldbuilding. Your question, I can see, is a valid one but you phrase it very vague and kind of flippant, and by the end you are nearly answering the question on your own. This makes it a bit unclear as to what it is you really wish to know and that you think that the SE:WB community can help you with. I would suggest that you structure this question like so: Premise, Problem, Question. That is: first you explain what the setting is. Then you explain your "dilemmas" or the choices that you as an author have. And finally you have one or more clear-cut questions. Sep 28 '16 at 13:42
• Excellent suggestion @MichaelKarnerfors Sep 28 '16 at 14:07

If you want to live on Mars, tunnels are a great idea. The radiation is one very good reason, and insulation efficiency until you can raise surface temperatures is another. You don't HAVE to live in tunnels, but if your civilization is xenophobic and trying to survive on its own, then tunnels are a great low tech way to make your life more pleasant.

The be-all-end-all of Mars colonization information is Red Mars. Its probably the most widely read fiction on the topic, and has all the science you want and more. If you are writing a story about Mars colonization and haven't read that, you are wrong. There are two sequels (Green Mars and Blue Mars) that are alright, but I wouldn't say are required reading.

• I am staying away from fictionalized accounts. I've read most of them and, although I enjoyed them, they do not inform this particular circumstance. I am trying to construct a real-world alternative, but the crux of the story is far more personal and, to me, interesting. No love stories, no invaders. Sep 21 '16 at 23:00

You can but why would you go to all the effort of burrowing underground?

The dust storms are not that bad http://www.nasa.gov/feature/goddard/the-fact-and-fiction-of-martian-dust-storms

YEs you also have to protect against radiation and cold, which make your walls thicker and more expensive.

But even underground you would need to pressurize your tunnels. Mars's Atmosphere is 1% as dense as earth's so you tunnels will either leak atmosphere or explode unless you lined them with a strong pressure resistant wall. A wall that will resist the pressure change could be as expensive as one to resist the temperature change, and you have already incurred the cost of digging.

• First, burrowing underground isn't the point. Building into the side of a mountain is. Thick walls are not expensive. They are already there. The "expensive" part is hollowing out the living spaces. There's no money, no NASA support. Just the equipment they brought with them and obtained as they saw what was happening on Earth. Dust storms are that bad. They can last for months and cover hundreds of kilometers. Sep 21 '16 at 23:06
• @PhyllisStewart Inside a mountain is underground (there is ground above you). You are right digging is the most expensive part but then you also need hundreds of meters of air tight corridor lining and that adds to the cost. By expensive and cost I mean the cost in time, energy, tools and people required, its still hard if they don't have money. The storms last a long time but they are not that strong, the air is 1% and dense so the force exerted by a 60 mph wind is the same as a .6MPH wind on earth you could walk in bare skinned, it wouldn't really impede someone with a pressure suite Sep 22 '16 at 0:13
• Earth money is irrelevant, € or US $are useless on Mars. You don't even have a river to throw them in, and i don't know if smoking is even allowed in your story, so lighting cigars is also doubtful. – Karl Sep 22 '16 at 2:41 • @Karl the cost is not money, it is time and machinery and energy. You will need hundreds of people manning a massive energy consuming machine then you need to keep in good repair as is slowly boors into a mountain. Sure you aren't spending$ to keep it going, but you are spending recourses that you could spend elsewhere. In economics we call this the opportunity cost (the next best thing you could have done) maybe make twice as many houses if you make them above ground Sep 22 '16 at 17:10
• The boring machines we use today to lay highways through mountains are quite powerful. We would not need much more power than that. Also, the LASER tech should be well advanced, which costs little. The cave-like housing should be carved into the face of the hills or lower in mountains. tunneling would go across and below the plains to reach the other two colonies.Repair stations will be automated and roboticized by then. Each colony will have about 1000 persons. Sep 23 '16 at 2:15

Tunneling under mountains is possible, but quite difficult and energy intensive for the desired results.

Thermal and radiation protection from the Martian environment could be easily done through the simple expedient of digging a trench, building a barrel vault inside and then covering the trench over with the spoil from the digging.

Barrel vaults are strong, easy to build and can be easily extended, so the colonists won't have much difficulty keeping up with expanding needs. Tunnelling between the different colony sites for transportation is simply an extension of this technique, but the expense of digging long distance tunnels for transportation might be counterproductive unless there is a lot of traffic.

Economics will be a strong driving force for the colonists, since they will need to economize on their use of time, resources and energy, so unless there is every compelling reason, colonists will avoid tunnelling into mountains and dig trenches instead.

• Remember the lighter gravity of Mars and the superb efficiency of large tunneling machines used even now on earth. I am fairly certain that LASER technology would be used for carving out living spaces. Would you want to live in a place where you could only look up at a yellow or gray sky? Much better to live as the American Indians did at Mesa Verde. Large quartz windows for viewing would give life some normalcy. Even through colonists don't know better, there is something about being human that requires a relationship to the environment. Sep 21 '16 at 23:03
• @PhyllisStewart How do you tunnel with a laser? That is a terrible idea. To drill with a laser you are basically heating up the target so much that is vaporizes than allowing the vapor to escape. This is 2 -3 orders of magnitude worse then breaking it and moving it. Sep 22 '16 at 0:20
• Lasers are huge energy hogs, and digging trenches or tunnels would avoid using them on energy costs alone. If you really need to make your environment more Earth like (although the vaulted ceilings of cathedrals can serve as a model of what a vaulted colony structure would look like), the walls and ceilings could be lined with LCD screens and you project sky or scenery as desired. Sep 22 '16 at 4:48