How to build a road on the moon? According to a recent astronomical proof-of-concept research paper published in Springer Nature's open-access academic journal Scientific Reports, it is possible to create paved roads and landing pads on the moon by using lasers to melt lunar soil to create harder layered materials.
Although the experiment was conducted on Earth using lunar dust substitutes, the findings demonstrate the feasibility of the technology and show that it can be replicated on the moon, thus becoming an important achievement of "a small step to pave the way for the moon". However, the author of the paper also reminds us that further research is needed to improve the process.
According to the paper, lunar dust is a major challenge for lunar rovers, because of low gravity, lunar dust will float everywhere when disturbed and may damage equipment. Therefore, infrastructure such as roads and landing pads are critical to alleviate the dust problem and facilitate transportation on the Moon, but the cost of transporting construction materials from Earth is high, so it is necessary to use existing resources on the Moon.
Renderings of roads and landing pads laid on the surface of the moon. Image Source: Scientific Reports
Based on this, the co-authors of the paper, Juan-Carlos Carlos Ginés-Palomares, Miranda Fateri, Alan University of Applied Technology, Germany, and Jens G Günster, Federal Center for Materials Research and Testing, Germany, together with colleagues and collaborators, A carbon dioxide laser was used to melt a fine-grained material called EAC-1A (developed by the European Space Agency as a lunar regolith alternative), simulating how lunar dust is melted into solid material by focused solar radiation on the moon. They experimented with laser beams of different intensities and sizes (up to 12 kilowatts and 100 millimeters wide, respectively) to create strong materials. The authors of the paper point out that although experiments have confirmed that crossing or overlapping laser beam paths can lead to cracking, they have developed a strategy to create a triangular, central hollow geometry with a 45 mm diameter laser beam, which is about 250 mm in size. They believe that this triangular material can be embedded in each other to create a solid surface in a large area of lunar soil, which can be used as a material for paving roads and landing pads on the lunar surface.
The authors also calculated that reproducing this experimental method on the moon would require transporting a lens of about 2.37 square meters from Earth to replace the laser as a sunlight focuser. Therefore, the equipment required is smaller, which may be an advantage in future lunar missions.
