When unmanned objects, such as satellites, are used for military purposes, do they become valid military targets according to international law?
No, the Outer Space Treaty, which represents the basic legal framework of international space law has no provision for this.
One main provision that is not allowed is:
Article IV
- States shall not place nuclear weapons or other weapons of mass destruction in orbit or on celestial bodies or station them in outer space in any other manner;
The treaty does not explicidly prohibit the placement of conventional weapons in orbit.
The use of satellites, whether they are used for taking images or secure communications, is not restricted by the Outer Space Treaty.
Article VIII
A State Party to the Treaty on whose registry an object launched into outer space is carried shall retain jurisdiction and control over such object, and over any personnel thereof, while in outer space or on a celestial body.
The destroyment by Party A of a satellite belonging to Party C simply because these services were made available to Party B would have the same legal effect as when Party C destroyed a Fighter Jet, belonging to Party A, that is firing a missile into the territory of Party B.
The Outer Space Treaty was opened for signature in the United States, the United Kingdom, and the Soviet Union on 27 January 1967, and entered into force on 10 October 1967. As of February 2022, 112 countries are parties to the treaty, while another 23 have signed the treaty but have not completed ratification.
Russia (ratification as the Soviet Union), the United States, the United Kingdom, most of the European Union countries, Australia, India have ratified the treaty. China accessed it after the ratification process was compleated.
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