With the increasing emphasis on space exploration, global space agencies are advancing toward the establishment of human settlements on the Moon, which is considered as a pivotal step for future extraterrestrial missions. In this context, the In Situ Resource Utilization (ISRU) strategy promotes the use of local lunar resources, such as regolith, to produce durable building materials. Alkali activation of lunar regolith emerges as a promising approach, minimizing dependence on terrestrial supply chains by generating cementitious binders capable of withstanding lunar environmental conditions. This study explores the potential of using lunar regolith simulants to synthesize alkali-activated materials suitable for lunar construction, with a particular focus on optimizing their fresh and hardened properties. It was observed that the high content of reactive silica and alumina provided by metakaolin significantly enhances the formation of N-A-S-H gel phases, thereby increasing both yield stress and compressive strength. Response surface methodology revealed that under a defined optimal condition the material reached a yield stress of 19.77 Pa and a compressive strength of 27.6 MPa. Additionally, incorporating 3% urea as an admixture markedly improved workability and reactivity, enabling a reduced liquid-to-solid ratio and enhanced compressive strength. Preliminary vacuum-curing tests simulating lunar environments further emphasized the importance of optimizing water content and additive selection to minimize void content and maintain dimensional stability under low-pressure conditions. This work represents a critical advancement toward sustainable lunar infrastructure, contributing both to scientific knowledge and practical applications in extraterrestrial engineering.