Trilateral agreement between the US, USSR, and UK banning:

	•	placement of nuclear weapons or “weapons of mass 
		destruction” in orbit around the Earth.
	•	installation of nuclear weapons or “weapons of mass 
		destruction” on the moon, on any other celestial body, or 
			in  outer space itself
	•	use of the moon or any celestial body for military 
		purposes,  including weapons testing of any kind. 

Eighty-six other nations have since signed the agreement.