Before NASA prepares to fly out to Mars, it intends to go back to a familiar location in order to establish a permanent settlement: the moon. The plan conveniently declines to answer one of the most important questions, namely: How does anyone create a permanent settlement on the moon?
Thanks to the European Space Agency, we might have an answer.
The ESA, architectural firm Foster + Partners, and 3D printing company Monolite are currently exploring the possibility of using 3D printers to transform lunar soil into habitable domes capable of shielding astronauts from radiation and micrometeoroids. The soil-based outer structure would house an inflatable dome that astronauts would live in; this inflatable skeleton would, of course, be sturdy enough to support the layers of moon-based material the 3D printers spread over it.
"Terrestrial 3D printing technology has produced entire structures," said Laurent Pambaguian, heading the project for ESA. "Our industrial team investigated if it could similarly be employed to build a lunar habitat."
The whole plan is predicated on the idea that it'd be significantly easier to build a settlement if humans didn't have to haul all the materials they needed from earth. Transporting a single pound of material to space costs $4,000, so the less taken, the better.
That's where 3D printing comes in. If astronauts can use material already on the moon (rocks, dirt, aliens... you know, moon stuff), then all space agencies will really need to send are the 3D printers and inflatable domes.
"3D printing offers a potential means of facilitating lunar settlement with reduced logistics from Earth," said Scott Hovland of ESA's human spaceflight team.
So can engineers really make a habitable building out of space dirt? They've already tested out many of the capabilities they're touting, simulating lunar soil and actually constructing walls in recreated moon-like environments.
"First, we needed to mix the simulated lunar material with magnesium oxide. This turns it into 'paper' we can print with," explained Enrico Dini, founder of Monolite. After this material is sprayed into something resembling a block, they added a binding salt to transform the paper into a stone-like solid that could be used for a building.
Yes, it sounds very impressive. As for whether or not it'll work up in space, Foster + Partners' Xavier De Kestelier doesn't see any reason why it wouldn't.
"As a practice, we are used to designing for extreme climates on Earth and exploiting the environmental benefits of using local, sustainable materials," he said. "Our lunar habitation follows a similar logic."
Okay, say we use this technology to build houses on the moon. What about food? What about water? The ESA doesn't venture into that territory, but NASA's breakthrough RASSOR prototype can prove to be an especially useful way to supply water.
As we reported on Wednesday, the American space agency is currently testing a new robot that would help astronauts extract water, ice, and fuel from the moon's surface. RASSOR would collect as much lunar soil as it could, then deliver its haul to a small processing plant that could separate water and store it for later use by astronauts. After the water is removed, whatever dust is left would be converted into air and fuel.
Granted, these technologies are still in development, but for the first time we're starting to piece together a picture of life beyond earth. The portrait is still blurry to be sure, but at this rate it might be completed much sooner than originally anticipated.