A gray powder that looks like ash can become something closer to stone when hit with the right beam of light. Engineers have shown that simulated lunar soil can be melted and layered into solid shapes using a laser-based 3D printing technique, producing materials that tolerate heat and mechanical stress. The approach could help future astronauts build tools, landing pads, and habitat components directly on the Moon instead of hauling heavy supplies from Earth. The work, led by researchers at The Ohio State University and published in Acta Astronautica, focuses on a manufacturing strategy known as laser-directed energy deposition, or LDED. It involves feeding powdered material into a laser-generated melt pool, where it rapidly cools and solidifies into a new structure. A construction material already waiting on the Moon Lunar regolith, the dusty layer covering the Moon’s surface, comes from billions of years of meteor impacts that shattered rock into fine fragments. Because actual samples are scarce, scientists often rely on laboratory substitutes. The team used a version called LHS-1, designed to mimic soil from …