3D printers are devices that extrude successive layers of material to form 3D objects. Scientists contemplating human travel to Mars have proposed that using this technology to create shelters for astronauts after they land could increase the viability of such missions. With this approach, materials found on Mars like the rusty iron oxide that makes the planet look red could be turned into shelters, doing away with the need to bring construction supplies from Earth.
If humans are ever to spend any time on Mars, they’ll need places to stay. Although Mars is the planet nearest to Earth and also the one that seems most suitable for eventual colonization, it is by no means easy to reach. The difficulty of getting there increases with every additional bit of cargo, so minimizing the load will be an important goal.
As one of its Centennial Challenges, NASA issued a call for the design of 3D-printed habitats that could be used for space exploration, like a mission to Mars. The agency picked 30 finalists for the $2.25 million challenge midway through Sept. 2015 and settled on the three top designs at the NYC Maker Faire on Sept. 27.
Over 160 design teams from around the world submitted their entries to NASA’S 3D Printed Habitat Challenge. Team Space Exploration Architecture and Clouds Architecture Office took home the $25,000 top prize for their ICE HOUSE design, a proposal that would leverage shallow permafrost on Mars to create frozen shelters. The second-place design envisions using regolith, the chunky, red mix of soil and rocks that is found all over Mars, to 3D print structures that could house up to four researchers.
Even with well over a hundred entries, the proposed designs share some important things in common. One is that virtually all of them make use of materials indigenous to Mars, as being able to do this is the most valuable thing that 3D printing might bring to the table. The best designs also directly address the challenges inherent in the not-especially hospitable environment on Mars.
Every viable design includes a way of turning something that is found in abundance on Mars into construction materials suitable for 3D printing. The high-profile proposal advanced by French firm Fabulous, for instance, centers around the extraction of iron oxide from Martian soil. The design also incorporates a layer of water sandwiched between 3D-printed walls to shield residents from solar radiation, another important requirement. Finally, the rounded shape of the habitat, a common feature of many proposed designs, will help the pressurized building maintain its structural integrity in the low-density atmosphere of Mars.
Structures of this kind would first be used to shelter small teams of astronauts as they settle in and conduct research. Decades from now, they could be used for the development of whole cities of Martian colonists.
While all of the top design proposals are well grounded in today’s technology and what is known about Mars, plenty of work remains to be done. The most compelling designs will require advancements in 3D printing capability, especially insofar as they center around materials that are not commonly used for that purpose today. As scientists learn more about what Mars is like in general, they will also be able to focus in further on the top requirements and the approaches that are most likely to work out in practice.