One of the challenges of building a habitat on Mars is going to be materials. Transporting enough materials to build shelter will add to the shuttle payload, so a plan for a shelter can be built from materials that are already available on Mars would be really useful.
To solve this interesting conundrum, one designer turned to a substance that has been the topic of much speculation and research about Mars: ice.
And, for its 3D-printed frozen habitat, called, appropriately, the Mars Ice House, Team Space Exploration Architecture and Clouds Architecture Office was awarded first prize and $25,000 in NASA's 3D Printed Habitat Challenge to design a 3D-printed Mars habitat.
"As water is the baseline resource for future outposts on a number of extra-terrestrial carbon-bodies, NASA has adopted a 'follow the water' approach towards exploration. As such, water, the essential building block of life, is our Team's primary material resource in the formation of the Ice House habitat design," the team wrote on their Mars Ice House website.
"Given the predicted abundance of water in certain areas on Mars, our approach takes full advantage of its properties as an indigenous material that acts both as a life-force to sustain a human and plant ecosystem, and, when 3D printed, as our primary fabrication material."
The translucent ice construction of the conical habitat would allow natural light to enter the space. Meanwhile, because water provides a highly effective radiation shield, it would protect the inhabitants from radiation that's stronger on Mars than Earth due to its thinner atmosphere.
The habitat's construction consists of an outer ice shell, with the habitat inside, for a double layer of protection. Inside the habitat, which has multiple levels, private and communal spaces are provided, as well as vertical hydroponic garden facilities for supplementing the crew's oxygen and food supplies.
The habitat would be built on a section of Mars that is known to have access to an ice table at a shallow depth of less than a foot beneath the surface, as well as a climate that maintains temperatures below freezing year-round.
Theoretically, when the ice is exposed to the thin, low-pressure Martian atmosphere, it would immediately sublimate, or turn into a gas. The idea would be to capture this gas and use the sun's radiation to heat it, turning it into a liquid. This liquid would then be pumped through a robot that climbs the walls and sprays a composite of water, fibre and aerogel along the layered ring structure of the habitat, using a low-volume, close-range nozzle that ensures that any water that freezes mid-trajectory will melt and refreeze upon impact with the wall. The team has successfully demonstrated this technique on Earth.
In order to protect the ice structure from sublimating, a membrane of Dyneema-reinforced EFTE plastic, manufactured on Earth and deployed by the Mars lander, would coat the exterior. An artificial interior atmosphere with higher pressure would keep the ice inside from sublimating too.
NASA also announced the second- and third-place winners. Team Gamma's rock habitat built around an inflatable hub won second place, with a prize of $15,000; and Team LavaHive's basaltic lava habitat won third place.
You can view all 30 finalists on the NASA 3D Printed Habitat Challenge website.