Astronomy
Customary International Law and Space Resource Extraction
Quick fact
Even though the Outer Space Treaty forbids national appropriation of celestial bodies, the U.S. Commercial Space Launch Competitiveness Act of 2015 asserts that U.S. citizens can own resources they extract from space, a claim supported by emerging customary practice.
Why this is interesting
As companies plan to mine the Moon, a 1967 treaty is being reinterpreted. But can a nation really claim a piece of an asteroid?
Read the full explanation
Understanding Customary International Law and Space Resource Extraction
International law isn't always written down; some rules become law through general acceptance and practice. Customary international law arises from states' consistent behavior (state practice) and their belief that such behavior is legally required (opinio juris). For space mining, there is currently no treaty that explicitly permits or forbids extraction. The Outer Space Treaty's Article II says that outer space and celestial bodies are not subject to national appropriation, but it doesn't clearly address resources. This ambiguity has led to two rival interpretations: one that treats celestial bodies as 'common heritage of mankind' (prohibiting any appropriation) and another that sees them as 'res nullius' (things belonging to no one, but free for taking). Recent national laws and the Artemis Accords, signed by some states, lean toward the latter view, potentially shaping what becomes accepted as customary international law.
A deeper explanation
Customary international law requires two elements: widespread and consistent state practice and a belief that such practice is legally obligated (opinio juris). For space resource extraction, state practice is sparse because only a few nations have enacted domestic laws, e.g., the U.S., Luxembourg, and the UAE. These laws assert that private entities have the right to own extracted resources. The Artemis Accords, signed by several countries (but not all major space powers), go further by affirming that resource extraction is consistent with the Outer Space Treaty and by promoting safety zones around resource extraction sites. However, because a significant number of states, like Russia and China, reject this interpretation, there is not yet a 'general' practice. The doctrine of 'persistent objector' allows states to refuse to be bound by a new customary rule they consistently and openly oppose. Thus, the role of customary law in space resource extraction remains uncertain: it is a field where customary law is still crystallizing, and its acceptance depends on how many states adopt this practice and whether they feel legally obligated to do so.