Any human feat of exploration needs roads – and the same goes for the Moon. But how do scientists hope to build lunar roads? Using lasers and moondust, of course.
When rovers drive on the Moon, the low levels of gravity mean dislodged moondust flies up and does not settle. This dust is ultra-fine and abrasive – and if it gets into equipment it can cause a lot of damage (moondust even eroded the Apollo missions’ spacesuits).
For transport systems on the Moon to be successful, solid roads and landing pads will be essential. But sending road-building materials to the lunar surface is expensive.
So researchers at Aalen University, Germany, hit a space exploration milestone when they discovered they could melt lunar soil to form a more solid, robust substance that locks in the extremely fine dust.
This material, which is essentially fused layers of moondust, will prevent dust disturbance not only from rovers – but also from rocket thrusters landing and starting up again.
For the study, published in Nature Scientific Reports, the team’s experiments on Earth used a substitute for lunar dust called EAC-1A, which the European Space Agency (ESA) developed for these kinds of experiments.
The team melted the EAC-1A using a carbon dioxide laser. However, on the Moon, this laser will be replaced with focused solar radiation – a giant lens of 2.37 square metres (25.5 square feet) would concentrate sunlight to melt moondust into 20cm wide triangular paving stones.
“We were able to consolidate material up to a depth of more than 20mm, which is quite massive,” Prof Jens Günster, corresponding author of the study, told BBC Science Focus. “We were very happy with the mechanical properties of the consolidated material.”
Once the solar lens is sent to the Moon, the road-building process will only use lunar resources.
Further research is needed to refine the process before it is fully operational on the Moon. However, Günster believes it could be possible within the next decade – in time for missions such as the Artemis return to the Moon, and NASA’s Lunar Gateway.
About our expert
Prof Jens Günster is the Head of Advanced Multi-materials Processing at Germany’s Bundesanstalt für Materialforschung und -prüfung (Federal Institute for Materials Research and Testing). His research has been published in the journals npj Microgravity, Frontiers in Bioengineering and Biotechnology, and Advanced Materials.
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