Colonizing the moon in the post-terrestrial era? Challenges for the management of the commons

Introduction The beginning of the 21 st century has fundamentally changed how humans interact with space, as we have moved past the characteristic rivalry of the Cold War into a new period where space is more accessible and holds major economic and strategic importance. This new “post-terrestrial era” seems to also require, though, a new regulatory approach to space and lunar activities, as it shifts from traditional, state-focused geopolitics to a bipolar governance perspective which sees the Moon not just as a new territory to be commercially exploited, but as a global strategic commons where economic interest must be balanced with defense, governance, and environmental protection. In this context, the rapid increase in Moon missions, fueled by strategic goals to control its important resources and build permanent bases, highlights the major shortcomings of current International Space Law (ISL) initiatives: rather than fostering a unified governance system, they seem to pave the way for regulatory fragmentation, which is prone to tensions and rivalry. At the same time, this dynamic underscores a pressing need to re-evaluate the rules that should govern humanity’s future on the Moon. Methods This study conducts a systematic comparative analysis of the legal frameworks shaping lunar activities. The methodology is based on the evaluation of two distinct generations of governance instruments, through the selection of four core thematic pillars: Lunar Governance (addressing authority and access), Peaceful Purposes (concerning non-militarization), State Accountability (for national activities), and Responsible Utilization (encompassing environmental and safety standards). The first generation is represented by the multilateral treaties of the 1960s-70s: the Outer Space Treaty (OST) of 1967 and the Moon Agreement of 1979. The second generation comprises the two competing contemporary frameworks: the U. S.-NASA Artemis Accords (2020) and the Sino-Russian International Lunar Research Station (ILRS) initiative (2021). Results The analysis identifies a critical paradigm shift in lunar governance. Thus, the first-generation treaties established a foundational, principle-based model of democratization, enshrining space as the “province of all mankind,” mandating exclusive peaceful use, and prohibiting national appropriation. However, their general provisions and/or low ratification rate created a legal vacuum for resources use and management, which now appears to be feasible. In response, the second-generation instruments offer more practical rules for operational challenges –particularly concerning resource extraction– but they do so through a fragmented, coalition-based approach. Consequently, the emergence of two competing visions paves the way for the securitization of lunar activities, legitimizing proprietary rights over resources, reflecting terrestrial geopolitical divides, and indirectly accelerating the militarization of space by prioritizing national strategic interests over collective governance. Discussion The findings reveal that the governance of space, and lunar activities in particular, is at a crossroads, shifting from inclusive multilateralism and commons-based management, to exclusive bilateralism, privatization and militarization. The research concludes that while the existing core of International Space Law (ISL) remains resilient, its foundational principle of non-appropriation is being reinterpreted to the point of alteration, to serve national and commercial agendas. In this context, it appears that the perceived necessity for space and lunar militarization stems not only from the technical requirements of mining operations and the protection of related sites, that could well be managed under an adapted international regime (i.e., similarly to other commons), but also from a weakening commitment to multilateral cooperation itself. Such weakening of cooperation encourages competitive and exclusionary policies. A more sustainable and peaceful path forward in the post-terrestrial era will therefore necessitate a clearer commitment to inclusive, widely ratified international frameworks that balance emerging economic ambitions with the original cosmopolitical vision of the Moon as a shared commons for humanity; such an approach is essential to prevent any destructive arms race and ensure the Moon’s equitable and responsible exploration and utilization.