Three Treaties Everyone Signed. One Almost No One Did.
The Outer Space Treaty set the foundation. Four more instruments followed to fill in specifics — three became routine, widely ratified plumbing. The fourth, the Moon Agreement, never won over a single major spacefaring nation, and why is a genuinely contested question, not a settled one.
Three Working Instruments
These three treaties fill in operational specifics the Outer Space Treaty left open — and unlike Module 1's principles, there isn't much of a "who benefits" story here. Every spacefaring nation has a practical interest in all three working as intended.
Rescue Agreement (1968)
What It Does
Requires states to render assistance to astronauts in distress or accident, and to return both astronauts and recovered space objects to the launching state. Broadly ratified — every spacefaring nation benefits symmetrically from a rule that could someday apply to its own crew.
Liability Convention (1972)
What It Does
Makes a launching state absolutely liable for damage its space object causes on Earth's surface or to aircraft in flight, and liable based on fault for damage elsewhere. Widely ratified, including all major spacefaring states.
Registration Convention (1976)
What It Does
Requires states to register the space objects they launch with the United Nations, creating a public record of what's in orbit and who launched it — basic tracking transparency every operator relies on.
The Liability Convention in Practice: Kosmos 954
In 1978, the Soviet nuclear-powered satellite Kosmos 954 broke up on re-entry and scattered radioactive debris across northern Canada. Canada invoked the Liability Convention's absolute-liability standard, and the USSR paid compensation for the cleanup — a concrete, real-world case of the treaty functioning exactly as written, not just a theoretical framework.
The Moon Agreement (1979)
The Rule: The Moon Agreement extends the Moon and other celestial bodies to be the "common heritage of mankind" — going further than the Outer Space Treaty's non-appropriation principle (Module 1) by calling for an international regime to govern any future resource exploitation, with benefits shared equitably among all states, developing nations included.
Who Signed, Who Didn't: Only a small number of states have ever ratified it — and critically, not one major spacefaring nation is among them. Not the US, not Russia (or the USSR before it), not China. A treaty specifically about how to share space resources has essentially no participation from any nation currently capable of extracting any.
Why the major powers stayed away is a real, unresolved dispute — not a question with one agreed answer.
A Practical Disincentive
One Reading
"Common heritage" was read as a direct disincentive to investment: no state or company will spend the billions required to extract lunar water ice or asteroid metals if the legal framework requires sharing the proceeds with every non-spacefaring nation on Earth, contributions notwithstanding.
Protecting a Head Start
Another Reading
The treaty's failure reflects powerful spacefaring interests choosing to preserve their first-mover advantage rather than a genuine practical objection — the same dynamic Module 1 raised about the original non-appropriation freeze, now applied to why the follow-up treaty that would have closed that gap was quietly abandoned.
Both are live positions in space law scholarship today. This course states them and stops there.
Because the Moon Agreement never took hold, the resource-rights question it tried to settle is still open — which is exactly why the US Commercial Space Launch Competitiveness Act, the Artemis Accords, and the objections to both need their own dedicated treatment in Module 4.
Key Terms
- Rescue Agreement
- The 1968 treaty requiring states to assist astronauts in distress and return them, and recovered space objects, to the launching state.
- Liability Convention
- The 1972 treaty making a launching state absolutely liable for damage its space object causes on Earth or to aircraft, and fault-based liable elsewhere.
- Absolute Liability
- A legal standard holding a party responsible for damage regardless of fault or negligence — the standard the Liability Convention applies to Earth-surface and aircraft damage.
- Registration Convention
- The 1976 treaty requiring states to register launched space objects with the United Nations, creating a public tracking record.
- Moon Agreement
- The 1979 treaty declaring the Moon and other celestial bodies the "common heritage of mankind" — ratified by few states and no major spacefaring nation.
- Common Heritage of Mankind
- A legal principle holding that certain resources belong collectively to all humanity, requiring international governance and equitable benefit-sharing rather than individual appropriation.
For This Module
Treaty texts and ratification status tables from the UN Office for Outer Space Affairs, historical documentation on the Kosmos 954 incident and its settlement, and published space law scholarship on the Moon Agreement's non-ratification. This module set should always be checked for current developments before publishing.
Continue the Sequence
Module 3 covers national space law and export control — how ITAR and national licensing regimes shape who can compete in satellite commerce.