A proof-of-concept study published in the Oct. 12 issue of Scientific Reports suggests that using lasers to melt lunar soil could create a harder, layered material that could be used to build roads and landing pads on the moon. Although these experiments were conducted on Earth using a moondust substitute, the demonstration of the technology's feasibility suggests that it could be replicated on the Moon.
Moon dust is a major challenge for lunar rovers because of the low gravity, and moon dust floats around when disturbed and can damage equipment. Infrastructure like roads and landing pads are therefore critical to mitigate dust problems and facilitate transportation on the Moon. However, transportation of construction materials from Earth is costly and it is necessary to use existing resources on the Moon.
Scientists at the University of Applied Sciences in Ahlen, Germany, the Federal Center for Materials Research and Testing and other institutions, this time used a carbon dioxide laser to melt a fine-grained material known as EAC-1A (developed by the European Space Agency as a replacement for lunar loam) in order to simulate how moondust is melted into a solid substance on the Moon by focused solar radiation. The team experimented with laser beams of different intensities and sizes (up to 12 kilowatts and 100 millimeters wide, respectively) to create the solid material. However, they found that employing crossed or overlapping laser beams could lead to breakage. For this reason they developed a strategy to use 45-millimeter-diameter laser beams to create a triangular-like structure with sides of about 250 millimeters and a hollow center, which could be embedded in each other to create solid surfaces in large areas of lunar soil to serve as roads and landing pads.
The team calculated that to reproduce this method on the Moon, a lens of about 2.37 square meters would need to be transported over from Earth to act as a sunlight focuser instead of a laser. The small size of the equipment required could be an advantage on future lunar missions.
