Living on another world isn’t going to be easy. The only way we can make it sustainable is figuring out how to use the stuff already on planets and moons to manufacture the materials we need. Bringing the base from Earth isn’t a viable option. At least, not yet.
There’s only so much stuff a rocket can carry past the pesky forces of gravity. And we are still a long way off from space platforms constructing and launching rockets from orbit. Right now, scientists have to think of ways we can use what’s on another world to help keep us there long-term.
This week, the European Space Agency revealed a proof-of-concept that could one day help moon colonists build settlements. They took simulated moondust and used concentrated sunlight to bake it. The result? A lunar brick.
“This was done on a 3D printer table, to bake successive 0.1 mm layers of moondust at 1000°C. We can complete a 20 x 10 x 3 cm brick for building in around five hours,” explains Advenit Makaya, who was overseeing the project for ESA.
The simulated moondust is volcanic material from Earth that’s been ground up to mimic the dust found on the moon.
Makaya’s team used the solar furnace at the DLR German Aerospace Center facility in Cologne to cook up the simulated lunar bricks. 147 curved mirrors focus sunlight into a beam of scorching light to melt the soil grains together. When the sun wasn’t cooperating, the scientists turned to a bunch of xenon lamps (the kind used in movie theaters).
The resulting bricks are comparable in strength to gypsum. They’ll undergo mechanical testing to see just how strong they are.
The proof-of-concept is already showing areas where improvements can be made. Several of the bricks were warped at the edges because the edges cooled faster than the middle. “We’re looking how to manage this effect, perhaps by occasionally accelerating the printing speed so that less heat accumulates within the brick,” adds Advenit.
More work needs to be done, but not too bad for a proof-of-concept. Plus, this brick-making was done in atmospheric conditions on Earth. How will the process change in a vacuum with more extreme temperatures? That’s a question a follow-up project from RegoLight is tackling right now.
RegoLight began their work in November 2015 and should wrap up in November 2017.
And like most work related to space, folks on Earth can also benefit. “Back on Earth, 3D printing of civil structures using solar power and in-situ resources could support rapid construction of post-disaster emergency shelters, removing long, costly and often inefficient supply chains,” says ESA’s Tommaso Ghidini.