The objective of the study was to investigate the performance and shielding abilities of lunar regolith-based geopolymer when reinforced with basalt fibres and cured under environmental conditions of the lunar surface. The geopolymer building materials should be suitable for
3D-printing on the Moon. Since there is a very limited supply of water on the moon, the study also focuses on lunar geopolymers with a reduced amount of water in the recipes, without the need for raw materials that cannot be resourced locally on the Moon.