Between Sovereignty and Freedom : Legal Challenges and Prospects for Delimiting Airspace and Outer Space
Keywords:
Space Delimitation, Airspace Sovereignty, Kármán Line, Functional Theory, Spatial Theory, Soft law, Interspace TheoryAbstract
This article investigates the longstanding legal dilemma of how to define the boundary between airspace, where states exercise full sovereignty, and outer space, which is governed by principles of freedom of use and non-appropriation. The lack of a universally accepted delimitation creates legal and operational uncertainties for both states and commercial actors, especially amid emerging technologies. Drawing on international treaties, state practice, soft law instruments, and scholarly theories, including spatialist, functionalist, and interspace approaches, this paper analyzes the competing legal doctrines and assesses their practical viability. The analysis shows that while fixed altitude boundaries such as the Kármán line provide clarity, they may become obsolete with technological advances, whereas functionalist solutions risk legal unpredictability. The paper argues that hybrid legal concepts like the interspace theory offer promising paths forward but face significant political and legal hurdles. It concludes that, although a binding treaty remains elusive, incremental progress is possible through soft law, regional agreements, and the gradual development of customary international law. Clarifying the legal status of near-space operations is essential to mitigate regulatory fragmentation, enhance legal certainty, and enable the sustainable growth of commercial space activities.
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