Making it on the Moon — 3D printing useful stuff with moon dust

Researchers at the European Space Agency have developed a 3D printing technology that would use lunar dirt to produce a range of parts and building materials that could be essential components of a future moon base.

The team has produced screws, gears, and assorted other small objects from a simulated moon-dust, and a light-activated glue-like chemical binder. They are built up in layers by a 3D printer, and the resulting objects have a strength and consistency similar to a ceramic.The printing can construct extremely fine detail to a precision of 50 microns or one-twentieth of a millimetre.

Any future moon base will rely heavily on materials and supplies shipped from Earth at prices on the order of millions of dollars per kilogram, says Advenit Makaya, an advanced manufacturing engineer at the European Space Agency, who was part of the team. Being able to make use of whatever local resources are available would be enormously valuable.

One resource that's going to be plentiful is lunar dirt, also known as moon-dust or regolith. Apollo astronauts brought back samples of this fine, powdery sand. Some of it they collected intentionally, but they also brought some back inadvertently because it thoroughly coated their space-suits and equipment, sticking on contact.

Since this material was so common on the moon, it made sense to see if it could be useful. However Makaya's team couldn't test their printer using real lunar regolith. The samples the astronauts returned in the 1970s were simply too valuable to use up this way.

Fortunately analysis of those samples showed that lunar dirt is made of materials that are quite common in sand on Earth: mostly silicon oxide, aluminum oxide and iron oxide. In fact some volcanic sands, are very close — both chemically and physically — to lunar regolith, and these sands were the materials the team used as their test material.

Making small parts will be useful, but the team is also interested in scaling this up to make building materials that could be used to construct a lunar habitat. For example, 3D printed bricks made using this method could be used for structural purposes.

This would, of course, require a lot of the glue-like binder, which would have to be shipped from Earth. That's why the team has also experimented with using heat to fuse lunar dirt into bricks.

The research is part of the European Space Agency's Urban project which is looking at different ways to use 3D printing to help construct a lunar base.

ESA Urban Project video summary