Governance Frameworks for Multigenerational Space Programs: From Mission Command to Autonomous Polity

Permanent human settlements beyond Earth will require governance structures that evolve from centralized mission command to autonomous self-governance as populations grow, communication delays increase, and economic independence emerges. Existing frameworks for space governance -- the Outer Space Treaty (1967), the Moon Agreement (1979), and the International Space Station Intergovernmental Agreement (1998) -- were designed for temporary expeditions, scientific outposts, and orbital laboratories, not for permanent, growing polities with populations measured in thousands. This paper proposes a four-phase Governance Evolution Model (GEM) for off-Earth settlements: Mission Command (6-50 crew), Governed Outpost (50-500), Self-Governing Settlement (500-10,000), and Autonomous Polity (10,000+). For each phase, we define decision rights, authority structures, dispute resolution mechanisms, and the relationship between the settlement and Earth-based institutions. We identify five quantitative transition triggers -- population threshold, ISRU self-sufficiency ratio, communication delay, economic independence index, and governance capacity score -- that determine when a settlement should advance to the next governance phase. A constitutional framework is proposed that includes unamendable foundational principles, a structured amendment process, explicit rights of off-Earth populations, and dissolution conditions. Institutional continuity mechanisms -- overlapping terms, distributed capability, endowment models, knowledge preservation protocols, and AI-assisted institutional memory -- address the multigenerational challenge of maintaining governance coherence across complete personnel turnover. The model is applied to a case study of a Venus atmospheric settlement at 50 km altitude, projecting a timeline from first crew arrival through autonomous polity status. We address open challenges including transition authority disputes, Earth-settlement sovereignty conflicts, and resource rights under existing international law. The framework has broad applicability to any off-Earth settlement scenario including Mars, the Moon, and free-space habitats.