Space

MIT's prize-winning Mars city concept topped by domed tree habitats

MIT's prize-winning Mars city concept topped by domed tree habitats
An MIT team won first place for urban design with the Redwood Forest, a series of woodsy habitats enclosed in open, public domes that would reside on the Martian surface
An MIT team won first place for urban design with the Redwood Forest, a series of woodsy habitats enclosed in open, public domes that would reside on the Martian surface
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Left to right: Team members George Lordos, Alpha Arsano, Caitlin Mueller, and Valentina Sumini
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Left to right: Team members George Lordos, Alpha Arsano, Caitlin Mueller, and Valentina Sumini
The habitats include an intricate network of subsurface tunnels
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The habitats include an intricate network of subsurface tunnels
An MIT team won first place for urban design with the Redwood Forest, a series of woodsy habitats enclosed in open, public domes that would reside on the Martian surface
3/3
An MIT team won first place for urban design with the Redwood Forest, a series of woodsy habitats enclosed in open, public domes that would reside on the Martian surface
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Most plans for Mars bases make becoming a colonist about as desirable as setting up house in an oil drum, but an MIT team has come up with a plan for a Mars city based on the architecture of a tree. Taking out first place in the Architecture section of the Mars City Design 2017 competition, the Redwood Forest concept is intended to provide settlers with not only protection against the harsh Martian environment, but open public spaces filled with plants and abundant water.

As Sir Elton John said, Mars ain't the kind of place to raise your kids. Though the Red Planet is the most habitable of the planets, aside from our own, in the Solar System, it is still a terribly hostile place. The nighttime temperatures put the Antarctic to shame, the air is only a hundredth the pressure of Earth's and is composed mostly of carbon dioxide, deadly UV radiation rains down during the day, and cosmic rays are present 24/7. It's also dry to the point where the soil is composed of corrosive substances with very unpleasant properties.

Due to these drawbacks, it's difficult to come up with designs for manned outposts that don't look like a collection of tins that make the Amundsen-Scott South Pole Station look like a luxury resort. To break away from this stereotype, the MIT team of nine students led by MIT postdoc Valentina Sumini and Assistant Professor Caitlin Mueller took an interdisciplinary approach that uses location and system architecture, as well as water harvested from the Martian polar ice caps to supply tree-like habitats, for a design capable of housing 10,000 inhabitants in shirt-sleeve comfort.

The habitats include an intricate network of subsurface tunnels
The habitats include an intricate network of subsurface tunnels

At first glance, the MIT habitats don't look very tree-like. They look more like giant glass balls sitting on the Martian plains, each housing 50 people. But, like real trees, much of the habitat is below the surface in the form of intricate tunnels that connect the spheres and provide protection from cold, radiation, micrometeorites, and other surface hazards.

"On Mars, our city will physically and functionally mimic a forest, using local Martian resources such as ice and water, regolith or soil, and sun to support life," says Sumini. "Designing a forest also symbolizes the potential for outward growth as nature spreads across the Martian landscape. Each tree habitat incorporates a branching structural system and an inflated membrane enclosure, anchored by tunneling roots. The design of a habitat can be generated using a computational form-finding and structural optimization workflow developed by the team. The design workflow is parametric, which means that each habitat is unique and contributes to a diverse forest of urban spaces."

The habitats rely heavily on water, but not just for drinking, agriculture, or public fountains. It's a key ingredient in making the domes habitable.

Left to right: Team members George Lordos, Alpha Arsano, Caitlin Mueller, and Valentina Sumini
Left to right: Team members George Lordos, Alpha Arsano, Caitlin Mueller, and Valentina Sumini

"Every tree habitat in Redwood Forest will collect energy from the sun and use it to process and transport the water throughout the tree, and every tree is designed as a water-rich environment," says Department of Aeronautics and Astronautics doctoral student George Lordos. "Water fills the soft cells inside the dome providing protection from radiation, helps manage heat loads, and supplies hydroponic farms for growing fish and greens. Solar panels produce energy to split the stored water for the production of rocket fuel, oxygen, and for charging hydrogen fuel cells, which are necessary to power long-range vehicles as well as provide backup energy storage in case of dust storms."

The team believes that the Mars tree habitats could find a niche on Earth as well, at high latitudes, deserts and the sea floor, for example. In addition, the hydroponics technology could provide city dwellers with fresh food and the tunnels could be used to ease congestion in urban areas.

The team took out first place in the Architecture section of the 2017 Mars City Design competition

Source: MIT

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10 comments
10 comments
SimonClarke
excellent habitat. Trees provide so much of what we need, the research that I have been carrying out shows that with Bamboo, Cotton and Balsa trees we can make most things that we will need. I also recommend that every dwelling within the habitat grow plenty of plants including their own salad foods.
Nik
As the Mars climate is like Antarctica, at best, and has less sunlight than the northern hemisphere in winter, the possibility of growing trees in a 'plastic bag' there, is Zero! ''The team believes that the Mars tree habitats .....etc.'' {belief = 'an acceptance that something exists or is true, especially one without proof.'} Forget solar panels, without nuclear power to provide heat and light, these people will be living in cloud coo-coo land, but not for long!
jd_dunerider
I doubt they could get one to function on Earth, let alone Mars.
Wolf0579
I will keep saying it until someone dies or I die. We need to try these things out on the MOON, first. Rescue is only 3 days away, as opposed to sixe months for Mars. Who are the bloody idiots fueling this Mars death-wish?
Matt Fletcher
Good concept, to spit the surface capsule into numerous capsules rather than one big capsule. The saying, "don't put all your eggs in 1 basket," comes to mind but the spheres shown sticks out to much. exposure should be at a shallower angle to deflect high speed wind storms. Spheres would probably have double door entry to both tunnels and outside, with pressure sensors to alarm people of accidents and extra panels for replacing damaged panels sitting inside for emergencies. Remember trees run on Turgor pressure and are less fragile then animals to pressure changes. Regardless, underground nuclear power would be a must for survival at first.
ctein
Dear Nick,
That isn't the way the physics work (and why do you imagine that the MIT folks couldn't do basic physics?)
Mars has less than 1% the atmosphere of earth's (which absorbs about 25% of the insolation). Combined with Mars' greater distance, a solar panel on Mars gets 50-70% (Mars' orbit is very eccentric) as much sunlight as one would on a sunny day on earth. Which is still a lot of power.
But wait (as they would say on the late night commercials), there's more! A high percentage of days on earth are not sunny. Whereas a very low percentage of days on Mars are not sunny. This varies LOTS with location, but overall it means roughly a 20+% efficiency loss on earth. That means Martian solar panels will generate between 65% and 90% of the power they would on earth. A very rough calculation, to be sure, but good enough to indicate that solar panels would work perfectly well on Mars.
Which is not to say you also don't want nuclear. (non-interruptible and diverse power supplies — good idea!)
As for the temperature differential, again, look to the atmosphere. Most heat loss from greenhouses on earth are due to conduction and convection with the atmosphere. Radiation is a very inefficient remover of heat. On Mars, conduction and convection losses through the atmosphere are less than 1% of what they are on earth. Even with very large temperature differentials it's likely that a bigger problem for the colony will be disposing of excess heat, not keeping things warm. Humans and human activity create lots of waste heat!
pax / Ctein
Nik
ctein--To keep heat in, you first have to have some heat! Thats something in short supply on Mars, thats why most of it is colder, very much colder than Antarctica. If there was sufficient heat to grow trees and plants on Mars, then Antarctica would be covered in forests. It isn't. Solar panels are very inefficient at converting light to electricity, so it would be impossible to use solar panels to produce enough additional electric light to grow trees. If you've not noticed it, trees in the Northern hemisphere lose their leaves in winter, due to low sunlight conditions, sunlight conditions that Mars never reaches, even on a good day. Pines in those extreme conditions are very slow growing. It may surprise you, but the heat in green houses mostly comes from the suns radiation, and the losses go out the same way. On Mars, they would need to be multiple glazed to keep heat in, and use special coated glass or plastic that reflects heat inwards, to limit heat loss by re-radiation. All this in a space capsule sent from Earth? Mars also gets major sand storms that would be likely to cause sever damage to any lightweight structures, and would just blow the structures shown away, or sandblast them into uselessness. Then, trees need water, lots of it, which is something that is noticeable for its significant absence on Mars, and they also need adequate nutrients, of the correct kind, another thing that cannot be guaranteed. Before I would trust my life to such fantasies, I would want to see them set up in a high cold desert, say in the Himalayas, and become fully productive. Before you start waffling about how physics works, you first have to understand how trees ''work'' otherwise your physics is irrelevant. To give you an example of the problem, Iceland has been attempting to reforest for years, and has planted millions of trees. They are hardly noticeable, as it has long winters with low light, and lots of cold, but still nothing even near as extreme as Mars.
ctein
Dear Nick,
No Sigh.
That really isn't the way any of that works.
Heat is not in short supply on Mars. Mars would only be 6% colder than Earth, due to less insolation, except for the fact that Earth has a nice thick insulating atmosphere that keeps the heat in. That boosts the earth's temperature by another 12%.
Mars still gets plenty of heat from the sun. Solar thermal is easy to collect, with high efficiency — look at the specs for well-designed solar water heaters on earth. On Mars, peak value is 500-700 W per square meter. Furthermore, all human activities generate heat and ultimately any energy consumed degrades to heat. Without an atmosphere to conduct/convect heat away, you have to WORK to get rid of the heat humans produce.
You're wrong about the primary source of heat loss in greenhouses - do the math, do the physics. Really, this is not arguable.
You're also wrong about what trees require. Go measure the light levels interior to a heavily forested area, and you'll find that the non-canopy trees (and other plants) get 10%-20% as much sunlight as trees out in the open. As already mentioned, the average sunlight on Mars is 50-70% of Earth's. Plenty of varieties of trees will be quite happy.
And, again, you just assume that the folks at MIT wouldn't bother to look up something this elementary. Because, really, it is very elementary. Instead of just arguing, try paying attention and learning Something. Maybe even look up their study and try seeing what they actually did consider and didn't consider? Instead of just assuming you're so much more brilliant and knowledgeable than people in MIT.
You keep harping on the "inefficiency" of solar panels, but that doesn't mean they're not adequate for generating electricity. A high-efficiency unit on Mars will produce about 2.5 kWh per square meter per day. A 20 m x 20 m array, which is hardly unreasonably large, gets you a megawatt hour per day. Oh yeah, and the stuff that doesn't get converted electricity can be captured as heat (because the panels absorbed most of the light that hits them)… and all that electricity ultimately goes back into heat. Like I said, heat is not in short supply! (Not so aside — your preferred solution of a nuclear power plant generates copious waste heat. Plenty for everyone.)
Again, this doesn't preclude the need for alternative power sources — storing overnight isn't a problem, but since dust storms on Mars can last for weeks you either need huge storage capacity or alternative ways of producing power. Probably you have both. Belt and suspenders.

This is all I'm going to say. If you want to come back with more irrelevant facts, be my guest. I'm posting this so that other people reading this article have accurate facts. Done here.
pax / Ctein
Nik
ctein: LOL! Your naivety is showing! This plan is based on using redwood trees to provide a climate within the enclosures. For that they will need water, one hell of a lot of it. Also,the soils are currently considered unsuitable for Earth plant life, so ALL the soil for these trees would require excavating, cleaning, and conditioning to make it suitable. That would also require water to wash the soil, which so far, is somewhat lacking on Mars. One average size tree, can transpire 40,000 gallons [151,000 litres] of water per year. That water has to be fluid. To raise it from the Mars average of -51 deg C to plus 20 deg C would require about 11 megawatts, supplied continuously for just ONE tree. All water on Mars, if any, is considered to be in the form of ICE! Trees cannot function in ice. If you travel the world, you will find there is something called 'the tree line' above which trees will not grow, because it is too cold, even if it is not frozen. This is apparent even in the the tropics, which has more than abundant sunshine. For trees to grow on Mars, the roots of the trees would need the soil to be defrosted and kept that way every day, 365 days of the year. The root system of a tree, takes up roughly the same volume as the canopy. So, that together with the water flow through just one tree, will consume multiple megawatts per year. It is proposed that these enclosures will have many trees. Therefore your 20x20 m solar panel array would have the equivalent effect to spitting in the Pacific. In addition, there has yet to be any confirmation that Mars actually has any significant amount of water, so all that is pure fantasy until such time as water is confirmed, and in sufficient quantity, and quality. Trees dont like salt water either. Also, given that solar panels have yet to exceed 25% efficiency, just to match the existing sunlight arriving on the surface of Mars, would require four times the area, covered by the panels, and a lot more than that will be required. So, to produce enough heat AND light for the proposed trees to thrive, solar panels would be useless. Only nuclear power will provide sufficient power, as I said in my first comment. However, at present, that also requires abundant water, of which there is none, so far, on Mars. It may be possible to site the power plants near the poles to use the cooling effect, but that would then require electric transmission lines over hundreds of miles. Which can be provided by their local Walmart I suppose? Mars has less sunlight than the northern forests on earth in winter, so, as the northern forests trees go into hibernation, during the winter, any trees on Mars, would be in permanent hibernation, without artificial lighting, or in simple terms, dead! Keep sighing!