Partial Nuclear Test Ban Treaty
The Partial Test Ban Treaty (PTBT), formally known as the 1963 Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water, prohibited all test detonations of nuclear weapons except for those conducted underground. It is also abbreviated as the Limited Test Ban Treaty (LTBT) and Nuclear Test Ban Treaty (NTBT), though the latter may also refer to the Comprehensive Nuclear-Test-Ban Treaty (CTBT), which succeeded the PTBT for ratifying parties.
The Ivy Mike test of 1952, an early thermonuclear detonation
Eisenhower and Strauss discuss Operation Castle, 1954
Macmillan (second from left) with Eisenhower in March 1957
US test detonation (part of Operation Hardtack II) conducted shortly before the start of the moratorium in 1958
Nuclear weapons tests are experiments carried out to determine the performance, yield, and effects of nuclear weapons. Testing nuclear weapons offers practical information about how the weapons function, how detonations are affected by different conditions, and how personnel, structures, and equipment are affected when subjected to nuclear explosions. However, nuclear testing has often been used as an indicator of scientific and military strength. Many tests have been overtly political in their intention; most nuclear weapons states publicly declared their nuclear status through a nuclear test.
The mushroom cloud from the Castle Bravo thermonuclear weapon test in 1954, the largest nuclear weapons test ever conducted by the United States
Subcritical experiment at the Nevada National Security Site
The Phoenix of Hiroshima (foreground) in Hong Kong Harbor in 1967, was involved in several famous anti-nuclear protest voyages against nuclear testing in the Pacific.
The first atomic test, "Trinity", took place on July 16, 1945.