Building Habitats for future Martian colonists is a very big concern for the colonists and critical to quality of life. This article is about the practical issues in designing safe and highly livable Martian Habitats, a little dreaming of what might be possible. If you don’t want to read too much of the technical details you can go down and look at the drawings and pictures to get the fantasy ideas in the Aesthetics section. I am very open to anyone who has their own ideas about habitats on Mars or knowledge of issues or opinions.
People frequently think that life on Mars would be necessarily very limited and certainly it could be very hard but I think we have to spend a lot of time thinking about this because small things might make a huge difference in quality of life for the colonists.
A key consideration in the life of Colonists will be the aesthetic issues of beauty and feeling of spaciousness. Since many of the things of danger on Mars conspire to force a smallness and dark underground feel it has become apparent to me that this would be a very hard sad life if we don’t think long and hard how to make it better.
If at all possible we would like to find a way to make the most of the Martian environment and beauty without compromising the safety of colonists. Therefore, we should think how we could make living on Mars truly beautiful and awe inspiring.
I really believe we will have a colony on Mars. It might be in 30 years or 100 years but it will happen. I would like to split my life in 2 and spend some time on Mars as a colonist but I also have reasons to stay here. So, these are dreams but very practical dreams. This is definitely possible. Whether these end up being the real way habitats are built is simply speculation. Fun speculation. Hopefully somebody who ends up designing such things finds these ideas useful but even if it inspires scifi authors or simply the imagination of some people that is good too.
Building The Safest Habitat
The ideal habitat from a safety and practical point of view would have the following characteristics:
a) Located with 15′ of soil between the outside wall and the residents
b) Small rooms with locking doors like a submarine
c) Be composed of materials that are hard and able to withstand damage mostly metallic or hard plastics
Frequently Mars habitats in popular media are pictured as bubbles with expansive views of the Martian terrain and sky like this but we really don’t know how to build such a structure today that would be practical.
One of the most magical things we are generally unaware of on Earth is the magnetic field of the planet. Mar’s magnetic field is barely able to register at 1/100th the strength of the Earths. While we know life can exist in high radiation environments it is generally very primitive single cellular life. Such life has numerous repair and protective elements for the DNA continuity. These mechnisms are amazingly good because if the DNA degrades from generation to generation any life at all would cease after a short time. Humans don’t have this enhanced level of protection and there is no imagined way we could attain such enhanced DNA protection intrinsically in our cells.
Unprotected Martian colonists will receive 0.3 Sieverts of radiation on their voyage to Mars. 1 Sievert is considered about a normal dose on Earth for a lifetime. Thus a round trip to Mars would subject people to a large and potentially cancer causing dose but not a death sentence. However, living on Mars is about 10-15 times the radiation of living on Earth which means a person of normal lifespan would expect to get 10 sieverts of radiation if they were exposed constantly to Martian environment. This is probably unacceptable and would probably result in 5 times the cancer of normal Earth population.
Worse, SPE are events where the sun emits large bursts of gamma rays can dose humans with vastly more radiation.
It is estimated that people could receive up to 3 sieverts of radiation and have approximately twice the risk of cancer. If we assume residents will have to expect this level of radiation then we have some flexibility on how much time residents can spend in open Mars terrain. If a resident spent 30% of their time in unprotected environment and the rest in a highly protected environment then they could keep exposure to roughly 3 sieverts over a lifetime.
Other Techniques to avert Radiation issues
A cure for cancer would be the best alternative possibly. If the cure is dangerous maybe this isn’t the greatest option but it is likely that before long we will greatly reduce the mortality of cancer. If this is the case residents could be exposed to larger doses up to 5 or even the 10 sieverts from full exposure and we will just deal with the consequences.
The first residents may be willing to accept higher death rates from cancer given the overall danger of death is so much higher anyway. Cancer may be one of the smaller risks overall so maybe protecting people is not as important but ultimately as we bootstrap our colony there will be a need to protect people. We should also assume that over time we will figure this out better so we will be willing to dose early colonists more and figure out how to improve our protection over time.
Artificial Magnetic Fields
One approach is simply to replicate the Earth’s magnetic field. NASA and the EU have a project called SR2S which has developed a superconducting cable that can be wrapped around the ship or habitats. This cabling once running and kept at 25K would provide continuous shielding of 100 times the strength of the Earths magnetic field and would allow at least a 10 meter or 30 feet protection zone. This approach requires very little power as the current through the superconducting cable would be self-sustaining. The magic of superconductors.
It is also possible to do this without superconductors using regular high powered electro-magnets. Sufficient solar power on Mars might enable significant magnetic field protected zones to be built and we could use less soil shielding. Electro-magnets would use about 1KW to keep a continuous shield of 100 meters. This is a lot of power and would require a substantial fraction of any colonies power. Nonetheless, solar power is plentiful on Mars given the lack of atmosphere and it is simply a matter of mass to transport enough solar panels of sufficient power
Superconducting cable while expensive to deliver would be ideal around large outside habitats as they would require low power consumption. More mobile environments may use a combination of some cabling or just pure electro-magnet. A single typical Telsa S car battery for instance could provide a week or more of magnetic shielding possibly much more depending on the space needed to be shielded.
It would be desirable to have underground and protected environments that don’t depend on any power requirements or superconductors to provide protection that can work in case of power interruption.
We may also want to use magnetic shielding as a supplement in case of SPE events. We will likely want an area in the colony where residents can gather during SPE events which has tremendous protection using a combination of natural shielding from soil and magnetic shielding. SPEs can last from minutes to 5 days. Most are shorter and less than a day. There are from 2 to 10 such events a year.
Different materials provide different levels of shielding. It is possible that we will discover new materials that could protect people. I wonder if anyone has thought of a electromagnet lined spacesuit or clothing that could be juiced up instantaneously based on the radiation in the immediate area. A personal magnetic field would be especially useful if you are caught outside when a SPE hits.
In general magnetic materials are heavy and inflexible. Being able to mine them from Mars would be an important factor in reducing costs to carry such weighty material to Mars.
Surprisingly one of the easiest to manufacture and most protective materials is also light. Polyethylene is well known as common plastic and produces a 90% reduction in radiation for a 1 inch layer. If we use polyethelene as one of the layers in a habitat or mobile facility combined with a much smaller magnetic field may produce terrific protection with lower power requirements.
Polyethelene or some variant is generally flexible and strong and could be used all over in space suits to reduce dramatically the total exposure of colonists in the field. Combined possibly with electromagnets the combination might be an effective lightweight shield for most radiation.
]I am sure over time we will discover other materials even more flexible and having other properties. The problem is how to manufacture more exotic materials on Mars before we have significant manufacturing capacity there.
The combination of things we know that are available and ways we have suggest we will be able to engineer good solutions for the colonists with flexibility in the design of the structures.
Overall, there are good ways to shield from radiation using a combination of materials, electromagnetic fields generated by magnets or by superconducting cable, soil from the planet. Each structure, habitat and living environment will use some combination of these things.
Since Mars atmosphere at the surface is extremely low and less than 1% of Earths density it is critical to prevent decompression. Humans can take about a minute of serious decompression before dying. Serious injury can result from much shorter duration.
The vision of many of large open areas of bubble like spaces suffers from practical considerations of breakage. Numerous proposals have been made over the years of double or triple layer materials that are transparent to build such domes. Unfortunately, I don’t know of any such material practical today.
There are materials being developed that have self-healing ability. We have seen materials in the lab that automatically rejoin when they are pierced assuming the structural damage isn’t too great.
All of these fancy materials are not likely to be easily manufactured on Mars initially so the colony would be greatly dependent on supplies from Earth. It will be a great improvement if we can find a way to 3D print layers or entire surfaces.
Recently, glass 3D printers have made great strides as well as printers for other exotic materials. In 9 years or so when these missions may take place we don’t know the state of this rapidly evolving field. We may be able to print many of the habitat structures instead of having to take them from Earth and assemble them.
The inflatable BEAM habitat being tested on the ISS as I write this article is opaque but has a double layer structure similar to the structure of the ISSs walls. It is not transparent. Building transparent versions of BEAM will be interesting. However, in my opinion the more likely kind of “transparent dome” would be built similar to the geodesic domes envisioned by Buckminster Fuller many years ago and still available at Epcot center in Florida.
Various glass like surfaces would be hard to bring to Mars both because of weight and potential breakage concerns. Nonetheless, we see tremendous advances in consumer glass like surfaces on all kinds of devices and with 3D printers now able to print glass we may be able to produce the structures on Mars from raw materials either acquired directly from Mars or delivered from Earth. The new Apple headquarters is built with new super strong glass to enable large panels not before possible. It is hard to anticipate what might be possible in 10 years.
We may be able to utilize soil of Mars for many of the walls. Having a material that can be sprayed for instance on the internal walls and seal them as well as provide insulation would be ideal.
Design and Safety Ideas
It is necessary for any habitat wall to contain a number of layers. We have learned on the ISS that a double layer structure is effective. The first layer can absorb most of the impact and then hopefully the source of the impact is mitigated so that it breaks up and disperses causing less damage to the second layer. I suspect we will want to use some insulation material between layers and possibly something that would help with magnetic field generation to deflect cosmic radiation. Standard design may incorporate 3 layers as standard.
Another concern for any wall material will be durability to Martian winds and soil exposure.
We will want to build greenhouses that are exposed to more direct sunlight. Therefore spending a good amount of time trying to have transparent surfaces that are safe in the martian environment is going to be important.
In the event of failure
In addition to the prevention of leaks and breakage very real thought will have to go into how to deal when such events occur. Fast re-compression, available air supplies, safety vehicles or suits, fast repair, autonomous repair should all be considered carefully in the design of any spaces.
In the case of breakage of the surface it would be ideal if the surface prevented somehow in most cases large escape of air so there is more time to get to safety or to evoke repair or simply to conserve lost resources. Materials that can be easily repaired, patched, replaced with minimal time is critical. Patch kits should be available everywhere. Detection of leaks should be possible and pinpointed quickly.
I can imagine that domes might have a “quick deploy” cover that can be very quickly put in place possibly automatically so that any breach is immediately replaced with an entirely new surface undamaged that can form a seal immediately. One could imagine a folded surface buried around the structure. When a breach is detected independent power supply immediately deploys the new canvas or whatever explosively possibly so that like an airbag it is deployed in a second or less. Possibly air is included in this device so that when the seal is made an emergency air supply is pumped in instantly.
Headsets with air supply contained could be located in close proximity to residents so any loss of pressure could at least protect the head quickly with a minimal supply of air. The main causes of permanent damage to humans is extended loss of pressure around the head. Protecting the head would extend dramatically the time before repressurization before death occurs.
Many solutions to this problem are possible but they all require careful analysis to make them practical for Mars and readily available to colonists.
Raising the air pressure on Mars (Minimal Terraforming)
Much has been made of terraforming Mars. Here is a great article on the topic. It is definitely a possibility at some point. What occurs to me is that we could raise the air pressure at the surface of Mars considerably to make living on Mars significantly easier without full terraforming. Using natural mining techniques leveraging known CO2 sources at the poles or underground we could pump more and more atmosphere into Mars to at least make safety less of a concern.
The atmosphere of Mars is around .01 Earth at the surface but a pressure of just .17-.24 Earth would be enough for people to walk around and live with some kind of headgear. You would still need to be protected from the temperature which is literally around -80F(-60C) for most of the surface and times of the day. Additional surface pressure might increase the temperature a little but I think it would be deadly cold without protective gear. The surface a few inches high at the equator of Mars during the day reaches 0C today.
Terraforming Mars will require gigantic amounts of power and tremendous amount of materials that will take decades to develop but it has been thought of quite extensively and seems possible. Elon Musk has suggested a quick way to generate a lot of atmosphere would be to nuke the poles. A simpler way to do this in more controlled way might be to place underground a nucelar reactor that would generate massive heat consistently for 30-100 years and gradually melt all the ice. Measures such as these will require extensive studying before adoption.
Eventually as the temperature rose people would be able to wear lighter garments when on the surface. In order for such gases not to immediately freeze and come out of atmosphere we will have to depend on a greenhouse effect of sorts. We could imagine building mining devices using solar power and would run continuously on Mars pumping whatever we could into the atmosphere, ideally greenhouse gases of some sort to help raise the temperature. This wouldn’t be trivial but given the abundance of solar power and materials on Mars it is not at all impractical to consider immediately starting such a project especially to see how it works, if the expected supply can be attained and how reliable it is, what problems we run into.
Let’s face it. Living on Mars could be really depressing. Without nature and rocks, living things or even a view of the surface, the stars and the sun people will potentially go crazy.
People need art, need beauty in their lives. I don’t believe this is optional or a luxury. It is a necessity and therefore we must find a way to bring beauty to our habitats. This means open spaces, transparent surfaces and lots of space. These are all anathema to safety and cost.
One possibility is to build structures with a combination of over and underground structures.
Virtual reality may be key to a livable world
With the advent of high resolution organic LEDs and other display technologies it is possible to create near lifelike realism. OLEDs are also flexible and could be formed into rounded surfaces. I expect that many rooms on Mars would use such monitors in many if not all rooms to provide outside views or views that were beautiful and awe inspiring to keep residents feeling a part of the Martian environment. I imagine these as being floor to ceiling type displays so that it was a totally encompassing experience.
Cameras located at strategic locations could provide real-time spectacular views of the Martian environment or any environment including Earth environments so that residents could feel less claustrophobic and surrounded by more natural and beautiful environments. Key to making such environments work besides the impressive display technology would be very high speed networking on the planet. It is likely we would have 100gbit to terabit networking all over the planet and into space as I’ve described earlier making such high resolution real-time displays possible.
I don’t believe that this is sufficient. Just because we can make any small room look like it is sitting at the edge of a precipice and for you to walk around in such environments would not replace the tactile need to feel the outside, water and natural plants and animals. Until Virtual Reality can create that for Colonists we will have to give them access to the real world by supplying real natural environments.
We must create Water and Streams, Lakes and Beach
I believe that we will have a plethora of water on Mars. Many lines of evidence point to significant water that flooded the planet at times. Here is a graphic of what Mars might have looked like:
A large amount of water is enormously beneficial for the colony. It means we can use water in life processes, manufacturing processes and for recreational activities like we do on Earth. Water is one of the critical elements of all life. We believe 50% of all life is in water. We should strive to have aquatic life on Mars as well.
One of the more important things to do early in the colony would be to create a lake of fresh water. Water cannot exist on Mars in liquid form so we would have to provide a very large protective dome. Such a dome would not necessarily have to be heated very much or even be inflated to high pressure for the water to remain in the domed environment.
We might create underwater lakes where we could control the environmental conditions. We can find depressions on Mars or existing trenches where we could wall off both sides and cover it with far less material than a full dome. However, domes may have an advantage. By leveraging special tarps that can concentrate the sun and insulate the water surface we may be able to elevate the temperature sufficiently to keep large bodies of water liquid. Having a large surface area of the lake exposed to sunlight will make it easier to keep the water above freezing.
Storing vast amounts of water would be both a long term safeguard as well building block for future industrialization and for recreation, food source or other purposes.
Due to the fact that Mars is warmer at the equator we might want to concentrate life there. However, we don’t know if that is where there is sufficient water. We may have to build aqueducts to transport water mined from around the planet to our lakes or reservoirs.
Find an existing Caldera close to one of the landing sites of the appropriate size as determined that would be feasible to fill in a couple years. Cover the Caldera with a very energy gathering blanket like transparent cover. Initially this may not need to be dome-like. Deliver water to the Caldera using piping from sources on the planet we can find reasonably closeby. Construct large solar array near the Caldera to supply power for artificial heating and to support other functions such as air generation. Provide additional space in the Caldera for beach and recreation. We should also add plants and fish to the caldera to start to build an ecosystem after it has reached a sufficient level. Eventually we may want to have artificial wave generation and wind generation.
Voila: Beach on mars.
The polar caps could turn into recreation areas of great excitement. CO2 skiing and snowshoeing could become exciting sports on Mars. It may be that some of the polar areas have significant hills that could be used for skiing. However, if not, we could reshape them for this. Anyplace on Mars is sufficiently cold that we could easily take water and spray snow as is done on the Earth to achieve snow like conditions.
Forests, Open Spaces, Nature
We need to have areas where there is large natural open space.
Building on Canyons and Sides of Mountains
Check out this incredible video flyby of Mariner Valley on Mars Fly-through