When astronauts return to the lunar surface they are probably going to be doing more driving than walking – but to keep billowing moondust at bay they are going to need roads. An ESA-led project tested the creation of roadworthy surfaces by melting simulated moondust with a powerful laser.

ESA’s PAVER — Paving the road for large area sintering of regolith – project investigated the feasibility of lunar roadmaking, led by Germany’s BAM Institute of Materials Research and Testing with Aalen University in Germany, LIQUIFER Systems Group in Austria, Germany’s Clausthal University of Technology and the Institute of Materials Physics in Space of the German Aerospace Center, DLR .

The PAVER consortium made use of a 12-kilowatt carbon dioxide laser to melt simulated moondust into a glassy solid surface, as a way of constructing paved surfaces on the face of the Moon. This laser is serving as a light source for our experiments, to take the place of lunar sunlight which could be concentrated using a Fresnel lens a couple of metres across to produce equivalent melting on the surface of the Moon.

During testing at BAM, the team achieved a spot size of 5-10 cm. Proceeding through trial and error, they devised a strategy using a 4.5 cm diameter laser beam to produce triangular, hollow-centred geometric shapes approximately 2.5 m in size. These could be interlocked to create solid surfaces across large areas of lunar soil which could serve as roads or landing pads.

This project originated from a call for ideas run by the Discovery element of ESA's Basic Activities through the Open Space Innovation Platform (OSIP), asking for research ideas related to off-Earth manufacturing and construction.