ESA creates its own “Lego bricks” to build a base on the Moon

The ESA has created its version of Lego bricks: it is a 3D print – made in collaboration with the construction company ICON – formed from the dust of a 4.5 billion-year-old meteorite (almost as old as the Solar System) discovered in 2000 in Northwest Africa. The development of these “space bricks” is part of the international Artemis program, which has aimed since 2017 to return astronauts to the Moon (by the end of 2026) and build a base there. However, since transporting construction materials from Earth to the Moon is too expensive and time-consuming, the goal is to use lunar regolith, the loose material covering the satellite’s surface, largely the result of meteorite impacts, to build the structures.

Since only a tiny amount of it exists on Earth, in the form of samples brought back during the Apollo missions, the closest possible substitute available on Earth had to be used. To obtain a material suitable for printing, pieces of meteorite were ground and then mixed with a small amount of polylactic acid – a type of biodegradable bioplastic – and a “regolith simulant,” a mixture of Earth minerals that resembles the composition of the lunar surface. Achieving the typical Lego brick shape has become a common test in this type of project, according to the ESA, even though precision is difficult to achieve at this scale with 3D printing. The construction system is the same as that of Lego. A type of interlocking connection creates that typical clutch power that makes the bricks so famously hard to separate – so much so that a special tool is now provided for this purpose. Lego will display 15 space bricks in its stores to inspire children to build their own “space shelter”.