The Outer Space Treaty and other agreements

The Outer Space Treaty (in full: The Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and other Celestial Bodies ) entered into force in 1967. It had been preceded by a number of resolutions by the UN General Assembly and years of discussion in the UN Committee on the Peaceful Use of Space. The decisive breakthrough came when the major adversaries, the United States and the Soviet Union, finally reached an agreement.

Since then, 107 states have ratified the Outer Space Treaty (July 2017), including almost every country that is actually involved in space activities. The Outer Space Treaty remains to this day a key document of international law when it comes to fostering the peaceful use of space and securing arms control in space. Other conventions such as the Environmental Modification Convention (ENMOD) of 1977 and the Moon Agreement of 1979 also contain provisions on arms control in space. However, these agreements do not outlaw a militarization of space that is above all made possible by current innovations in conventional weapon technology.

Content of the Outer Space Treaty

The Outer Space Treaty sets out the principles to govern space activities. It is premised on a “common interest of all mankind in the progress of the exploration and use of outer space for peaceful purposes” (Preamble). Outer space and the Moon and other celestial bodies are declared to be the “province of all mankind”. This rules out their appropriation by individual nations (Article II). The Treaty states that international law, including the UN Charter, shall also apply to space, the Moon and other celestial bodies (Article I and III).

With regard to militarization, the treaty contains the following provisions (Article IV):

  • All the states parties undertake to “not to place in orbit around the Earth any objects carrying nuclear weapons or any other kinds of weapons of mass destruction, install such weapons on celestial bodies, or station such weapons in outer space in any other manner.”

  • There is a general ban on “the establishment of military bases, installations and fortifications, the testing of any type of weapons and the conduct of military manoeuvres on celestial bodies”.

While a militarization of the Moon and other celestial bodies is comprehensively forbidden, the Outer Space Treaty only partially restricts military uses of space. Only the stationing in space of nuclear and other weapons of mass destruction is explicitly outlawed. It does not forbid the destruction of objects in space, such as satellites or rockets, from the ground or the air. Even the detonation of nuclear weapons in space that are launched from Earth or from the air is still allowed. Such nuclear detonations in space are in fact a potential method of intercepting missiles, which has long been researched by US and Soviet /Russian scientists. Nor is there any rule against the stationing of conventional active weapons or military surveillance, communication and navigation satellites in space. Finally, the Treaty does not prohibit the traversing of space by conventional missiles or missiles fitted with weapons of mass destruction.

Background to the Outer Space Treaty

In 1957, the Soviet Union succeeded in placing the first ever artificial satellite in Earth’s orbit. In so doing, Moscow was also demonstrating its ability to target US territory with intercontinental missiles. Thus, for a certain period, the Soviet Union had a lead over the United States in the field of space and missile technology. It was in this situation that the US administration proposed, in 1958, a ban on any testing of weaponized intercontinental missiles. The Soviet Union declared in response that it was willing to outlaw intercontinental ballistic missiles if the ban were accompanied by an undertaking to close all military bases abroad—from which US forces could threaten the Soviet Union by deploying aircraft and medium-range missiles. Washington rejected the Soviet counter-proposal, not wishing to jeopardize American military superiority in this field.

It was soon after the Sputnik launch by the Soviet Union that discussion began within the United Nations on the need to ensure peaceful uses of space and—partly in connection with proposals for “comprehensive and complete disarmament”—on arms control in space. But when, in the early 1960s, the Soviets lost their technological lead, Washington lost interest in an agreement to ban weapons from passing through space.

There was, however, a breakthrough—aided by pressure from international public opinion—in 1963 on a partial ban on nuclear testing. The Partial Test Ban Treaty forbade nuclear tests under water, in the atmosphere and in space. In space at least, no such tests had by then been conducted. The treaty was jointly proposed and later ratified by the United States, the United Kingdom and the Soviet Union.

The early 1960 also saw, in a parallel development, discussions and negotiations mainly within UN bodies aimed at regulating space activities and prohibiting weapons of mass destruction in space. After numerous resolutions to this end in the UN General Assemblies, the parties agreed in 1967 to adopt the Outer Space Treaty. It contained a compromise position inasmuch as the military use of space was only restricted to a very limited degree. The treaty did not obstruct the military strategies of the superpowers. It did, however, at least represent an advance on the position demanded by the US-American generals. The Joint Chiefs of Staff had been insisting that the deployment of smaller nuclear weapon be exempted from the ban, but Washington ultimately rejected this stance. The Treaty has since been ratified by 107 countries (July 2017). They include all the space-faring nations apart from Iran, which has so far signed but not ratified the treaty

Developments after 1967

Arms control in relation to space continued to play a role in later agreements, especially the Anti-Ballistic Missiles (ABM) Treaty agreed in 1972 between the United States and the Soviet Union.

Space was also referred to in the 1977 Environmental Modification Convention (ENMOD) and the 1979 Moon Treaty. Under ENMOD, now signed by 77 states (June 2015), the parties undertake not to engage in the military or otherwise hostile use of environmental modification techniques on Earth, in the atmosphere or in space. As for the Moon Treaty, the section on arms control repeats the demilitarization provisions found in the 1967 Outer Space Treaty, but with special reference to the Moon. However, only fifteen states have ratified the Moon Treaty and, critically, the major space-faring nations, the USA, Russia and China, are not among them.

Bringing space law up to date

In view of technological advances and the wide gaps in the Outer Space Treaty, there have been discussions over many years, especially in the UN framework, of measures to prevent an arms race in space. Resolutions to this end have always been endorsed by a large majority in the annual UN General Assembly. In 2008, Russia and China jointly submitted to the Geneva Disarmament Conference a draft treaty aimed at “Prevention of the Placement of Weapons in Outer Space, the Threat or Use of Force Against Outer Space Objects”. International associations of scientists have elaborated proposals on how weapons and armed conflict in space can be prevented by a preventive arms control regime. They have so far remained fruitless, however, in the face of American rejection of arms control agreements for space.

Sources and further information

BICC 11/2013


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