Operation Ivy was a series of nuclear tests conducted by the United States in 1952. It marked the first successful detonation of a thermonuclear device, also known as a hydrogen bomb. The tests took place at Bikini Atoll in the Marshall Islands and were part of the broader Cold War nuclear arms race. The most notable test, Ivy Mike, occurred on November 1, 1952, and yielded an explosion equivalent to 10.4 megatons of TNT. This test demonstrated the potential power of thermonuclear weapons and significantly influenced military strategy and international relations during the Cold War era.