For the last decade or so, there has been a low hum of talk about returning to the moon and potentially setting up some type of moon base. Such a venture would be enormously expensive, but breakthroughs in terrestrial 3D printing could lower that price tag by a substantial amount.
The ESA is investigating the possibility of using lunar soil as fuel for 3D printers and printing a moon base on site. Laurent Pambaguian, the head of this investigatory project, said, “Terrestrial 3D printing technology has produced entire structures. Our industrial team investigated if it could similarly be employed to build a lunar habitat.”
When you build your base on site, out of materials found around you, all of the sudden, the need to bring along your own building materials disappears. A few industrial 3D-printers are much more manageable than entire sections of a habitat complex. The research team designed a lunar base to maximize the strength of 3D printing techniques and printed a 1.5 ton building block for the proposed lunar habitat as a demonstration.
Hypothetically, the lunar 3D printer will mix lunar dust with magnesium oxide which will allow the material to be molded into the desired shape. The final application of a structural “ink” will turn that pliable substance into a stone-like material and you are one your way to printing a lunar outpost. Working in a vacuum poses the most immediate obstacle.
The printing material behaves very much like a liquid. In the vacuum of space, liquids have a nasty habit of boiling away. When your building material won’t stay pliable long enough to work with, you can see how this causes problems. Fortunately, Pambaguian and his team have already started working on this problem with small-scale printing jobs. The “proof of concept” test printed an object using 2mm droplets and worked like a dream.
The temperature extremes on the lunar surface are the next obstacle to address, which should be “easy” compared to printing in a vacuum. Then again, there is also the matter of the Moon's toxicity which is a whole other can of worms.