Starfish Prime: The Day the US Detonated a Megaton Bomb in Space

The explosion remains the largest nuclear test ever conducted in space. Its consequences were immediate and persistent, damaging multiple satellites and creating radiation belts that lingered in Earth's orbit for over five years. The sheer scale of the disruption signaled the volatile risks of high-altitude testing, prompting a global shift in nuclear policy.

By 1963, the United States, the Soviet Union, and the United Kingdom signed the Partial Nuclear Test Ban Treaty, effectively outlawing tests in the atmosphere, underwater, and in outer space. This momentum culminated in the 1967 Outer Space Treaty, which remains the cornerstone of international space law. Today, the agreement binds 115 nations to the principle that space must be used strictly for peaceful purposes. It explicitly forbids the placement of weapons of mass destruction in orbit and mandates that celestial bodies remain free from territorial claims by any single nation.