Nuclear weapons tests

Over 2,000 nuclear tests have been staged by the eight nuclear powers in over a dozen different sites around the world.Main article: Nuclear testing
Nuclear testing is usually the way that a country has announced its nuclear capability in the past, with a few exceptions. Throughout the Cold War, the United States and the Soviet Union performed hundreds of test nuclear detonations. Concerns about environmental effects of nuclear fallout led to the signing of the Partial Test Ban Treaty in 1963, which prohibited everything but underground nuclear testing. In 1996, the Comprehensive Test Ban Treaty was created, banning all nuclear testing, but not all nuclear states have signed it.

Nuclear testing by country breaks down as follows:

United States: 1,050 tests (involving 1,125 devices, 331 atmospheric tests), most at the Nevada Test Site and the Pacific Proving Grounds on the Marshall Islands, with ten other tests taking place at various locations in the United States, including Alaska, Colorado, Mississippi, and New Mexico (see nuclear weapons and the United States for details).

Soviet Union: between 715 and 969 tests, most at Semipalatinsk Test Site and Novaya Zemlya, and a few more at various sites in Russia, Kazakhstan, Turkmenistan, and Ukraine. As of 2006, the WMD of the former Soviet Union are controlled by Russia.

United Kingdom: 45 tests (21 in Australian territory, including 9 in mainland South Australia at Maralinga and Emu Field, many others in the U.S. as part of joint test series)

France: 210 tests, mostly at Reggane and Ekker in Algeria, and Fangataufa and Mururoa in French Polynesia.

China: 45 tests (23 atmospheric and 22 underground, all conducted at Lop Nur Nuclear Weapons Test Base, in Malan, Xinjiang)

India: between 5 and 6 tests, at Pokhran.

Pakistan: between 3 and 6 tests, at Chagai Hills.

North Korea: 1 test, at approximately 15.4 kilometers northwest of Hwadae, in Hamgyong Province.

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Additionally, there may have been at least three alleged/disputed/unacknowledged nuclear explosions . Of these, the only one taken seriously as a possible nuclear test is the Vela Incident, a possible detection of a nuclear explosion in the Indian Ocean in 1979 hypothesized to be a joint Israeli/South African test.

Alleged tests

There have been a number of significant alleged/disputed/unacknowledged accounts of countries testing nuclear explosives. Their status is either not certain or entirely disputed by most mainstream experts.


Japan

There is a disputed report about the Japanese atomic program being able to test a nuclear weapon in Korea on August 12, 1945, a few days after the atomic bombings of Hiroshima and Nagasaki on August 6 and 9, and three days before the Japanese surrender on August 15, but this is seen as being highly unlikely by mainstream historians. See Japanese atomic program for more information.


Israel/South Africa

In what is known as the Vela Incident, Israel and/or South Africa may have detonated a nuclear device on September 22, 1979 in the Indian Ocean, according to satellite data. It is not certain whether there was actually a test, also it is not known who would have been responsible for it. See Vela Incident for more information.


North Korea

On September 9, 2004 it was reported by South Korean media that there had been a large explosion at the Chinese/North Korean border. This explosion left a crater visible by satellite and precipitated a large (2 mile diameter) mushroom cloud. The United States and South Korea quickly downplayed this, explaining it away as a forest fire which had nothing to do with the DPRK's nuclear weapons program. See Ryanggang explosion for more information.


Germany

Hitlers Bombe, a book published in German by the historian Rainer Karlsch in 2005, has alleged that there is evidence that Nazi Germany performed some sort of test of a "nuclear device" (a hybrid fusion device unlike any modern nuclear weapons) in March 1945, though the evidence for this has not yet been fully evaluated, and has been doubted by many historians.



From the first nuclear test in 1945 until the latest tests by North Korea in 2006, there was never a period of more than 22 months with no nuclear testing. The period from June of 1998 to the 2006 North Korean nuclear test was by far the longest period since 1945 with no acknowledged nuclear tests.


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Tests of live warheads on rockets

The Frigate Bird explosion seen through the periscope of USS Carbonero (SS-337)Missiles and nuclear warheads have usually been tested separately, because testing them together is considered highly dangerous (they are the most extreme type of live fire exercise). The only US live test of an operational missile was the following:

Frigate Bird - on May 6, 1962, a UGM-27 Polaris A-1 missile with a live 600 kt W47 warhead was launched from the USS Ethan Allen (SSBN-608); it flew 1900 km, re-entered the atmosphere, and detonated at an altitude of 3.4 km over the South Pacific. The test was part of Operation Dominic I. Planned as a method to dispel doubts about whether the USA's nuclear missiles would actually function in practice, it had less effect than was hoped, as the stockpile warhead was substantially modified prior to testing, and the missile tested was a relatively low-flying SLBM and not a high-flying ICBM.
Other live tests with the nuclear explosive delivered by rocket by the USA include:

Operation Argus - three tests

On August 1, 1958, Redstone rocket #CC50 launched nuclear test Teak that detonated at an altitude of 77.8-km. On August 12, 1958, Redstone #CC51 launched nuclear test Orange to a detonation altitude of 43 km. Both were part of Operation Hardtack and had a yield of 3.75 Mt
On July 9, 1962, Thor missile 195 launched a Mk4 reentry vehicle containing a W49 thermonuclear warhead to an altitude of 248 miles (400 km). The warhead detonated with a yield of 1.45 Mt. This was the Starfish Prime event of nuclear test operation Dominic-Fishbowl
In the same series in 1962: Checkmate, Bluegill, Kingfish, and Tightrope
The Soviet Union tested a number of nuclear explosives on rockets as part of their development of a localised anti-ballistic missile system in the 1960s.

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