In a conceptual rendering, astronauts watch robots 3D-print structures out of processed lunar dirt. (Credit: Icon Technology)
The raw material for the first such structure is already on the Moon: the surface layer of soil, or regolith (PDF(Opens in a new window)) to geologists. NASA’s plans for long-term exploration of the Moon and, eventually, Mars rely heavily on generating needed materials and supplies from what’s on the ground there—what it calls “In situ resource utilization(Opens in a new window)”—instead of shipping everything from Earth.