List of nuclear weapons tests

The following is a list of nuclear test series designations, organized first by country and then by date. For more information on countries with nuclear weapons, see List of countries with nuclear weapons. For more information on nuclear weapon arsenals, see List of nuclear weapons.

United States of America
The United States conducted around 1,054 nuclear tests (by official count) between 1945 and 1992, including 216 atmospheric, underwater, and space tests. Some significant tests conducted by the United States include:
 * The "Trinity" test on 16 July 1945, was the first-ever test of a nuclear weapon (yield of around 20 kt).
 * The Operation Crossroads series in July 1946, was the first postwar test series and one of the largest military operations in U.S. history.
 * The Operation Greenhouse shots of May 1951 included the first boosted fission weapon test ("Item") and a scientific test which proved the feasibility of thermonuclear weapons ("George").
 * The "Ivy Mike" shot of 1 November 1952, was the first full test of a Teller-Ulam design "staged" hydrogen bomb, with a yield of 10 megatons. This was not a deployable weapon: With its full cryogenic equipment it weighed some 82 tons.
 * The "Castle Bravo" shot of 1 March 1954, was the first test of a deployable (solid fuel) thermonuclear weapon, and also (accidentally) the largest weapon ever tested by the United States (15 megatons). It was also the single largest U.S. radiological accident in connection with nuclear testing. The unanticipated yield, and a change in the weather, resulted in nuclear fallout spreading eastward onto the inhabited Rongelap and Rongerik atolls, which were soon evacuated. Many of the Marshall Islands natives have since suffered from birth defects and have received some compensation from the federal government. A Japanese fishing boat, the Fifth Lucky Dragon, also came into contact with the fallout, which caused many of the crew to grow ill; one eventually died.
 * Shot "Argus I" of Operation Argus, on 27 August 1958, was the first detonation of a nuclear weapon in outer space when a 1.7-kiloton warhead was detonated at 200 kilometers' altitude during a series of high-altitude nuclear explosions.
 * Shot "Frigate Bird" of Operation Dominic I on 6 May 1962, was the only U.S. test of an operational ballistic missile with a live nuclear warhead (yield of 600 kilotons), at Christmas Kiritimati Island in the Pacific. In general, missile systems were tested without live warheads and warheads were tested separately for safety concerns. In the early 1960s there were mounting questions about how the systems would behave under combat conditions (when they were "mated", in military parlance), and this test was meant to dispel these concerns. However, the warhead had to be somewhat modified before its use, and the missile was only a SLBM (and not an ICBM), so by itself it did not satisfy all concerns.
 * Shot "Sedan" of Operation Storax on 6 July 1962 (yield of 104 kilotons), was an attempt at showing the feasibility of using nuclear weapons for civilian, peaceful purposes as part of Operation Plowshare. In this instance, a 1280-feet-in-diameter and 320-feet-deep explosion crater, morphologically similar to an impact crater, was created at the Nevada Test Site.

Soviet Union


The Soviet Union conducted 715 nuclear tests (by official count) between 1949 and 1990, including 219 atmospheric, underwater, and space tests. Most of them took place at the Semipalatinsk Test Site in Kazakhstan and the Northern Test Site at Novaya Zemlya. Additional tests were conducted at various locations in Russia and Kazakhstan, while a small number of tests were conducted in Ukraine, Uzbekistan, and Turkmenistan.

In addition, a large-scale military exercise was conducted by Soviet army to explore the possibility of defensive and offensive warfare operations during nuclear war. The exercise, under code name of "Snowball", involved detonation of a nuclear bomb twice as powerful one used in Nagasaki and approximately 45,000 soldiers coming through the epicenter immediately after the blast The exercise was conducted on September 14, 1954, under command of Marshal Georgy Zhukov to the north of Totskoye village in Orenburg Oblast, Russia.

Some significant Soviet tests include:
 * Operation First Lightning/RDS-1 (known as Joe 1 in the West), August 29, 1949: first Soviet nuclear test.
 * RDS-6s (known as Joe 4 in the West), August 12, 1953: first Soviet thermonuclear test using a sloika (layer cake) design. The design proved to be unscalable into megaton yields, but it was air-deployable.
 * RDS-37, November 22, 1955: first Soviet multi-megaton, "true" hydrogen bomb test using Sakharov's "third design", essentially a re-invention of the Teller-Ulam.
 * Tsar Bomba, October 30, 1961: largest nuclear weapon ever detonated, with a design yield of 100 Mt, de-rated to 50 Mt for the test drop.
 * Chagan, January 15, 1965: large cratering experiment as part of Nuclear Explosions for the National Economy program.

The last Soviet test took place on October 24, 1990. After the dissolution of the USSR in 1992, Russia inherited their former nuclear stockpile, while Kazakhstan inherited the Semipalatinsk nuclear test area including one unexploded bomb, later blown up with conventional explosives by a team invited from the USA. No testing has occurred in the lands of the USSR since its dissolution.

United Kingdom
The United Kingdom has conducted 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). Tests include:


 * Operation Hurricane, October 3, 1952 (first atomic bomb)
 * Operation Totem, 1953
 * Operation Mosaic, 1956
 * Operation Buffalo, 1956
 * Operation Antler, 1957
 * Operation Grapple, 1957–1958 (first hydrogen bomb)

Last test: Julin Bristol, November 26, 1991, vertical shaft.

Atmospheric tests involving nuclear material but conventional explosions:


 * Operation Kittens, 1953-1961 (initiator tests using conventional explosive)
 * Operation Rats, 1956-1960 (conventional explosions to study dispersal of uranium)
 * Operation Tims, 1955-1963 (conventional explosions for tamper, plutonium compression trials)
 * Operation Vixen, 1959-1963 (effects of accidental fire or explosion on nuclear weapons)

France
France conducted 210 nuclear tests between February 13, 1960 and January 27, 1996.
 * Operation Gerboise bleue, February 13, 1960 (first atomic bomb) and three more: Reggane, Algeria; in the atmosphere; final test reputed to be more intended to prevent the weapon from falling into the hands of generals rebelling against Charles de Gaulle than for testing purposes.
 * Operation Agathe, November 7, 1961 and 12 more: In Ekker, Hoggar Algeria; underground
 * Operation Aldébaran, July 2, 1966 and 45 more: Moruroa and Fangataufa, French Polynesia; in the atmosphere;
 * first hydrogen bomb: August 28, 1968 Canopus (Fangataufa)
 * Operation Achille June 5, 1975 and 146 more: Mururoa and Fangataufa, French Polynesia; underground
 * last test: January 27, 1996 Operation Xouthos (Fangataufa)

China
The People's Republic of China conducted 45 tests (23 atmospheric and 22 underground, all conducted at Lop Nur Nuclear Weapons Test Base, in Malan, Xinjiang)
 * First test: "596": October 16, 1964
 * First hydrogen bomb test: "Test No. 6" - June 17, 1967
 * 200 kt-1 Mt atmospheric test, June 17, 1974 (16th test)
 * Last atmospheric test: October 16, 1980. This would also be the last atmospheric nuclear test by any other country
 * Last test: July 29, 1996, underground.

India
India announced it had conducted a test of a single device in 1974 near Pakistan's eastern border under the codename Operation Smiling Buddha. After 24 years, India publicly announced five further nuclear tests on May 11 and May 13, 1998. The official number of Indian nuclear tests is 6, conducted under two different code-names and at different times.
 * May 18, 1974: Operation Smiling Buddha (type: implosion, plutonium and underground). One underground test in a horizontal shaft around 107 m long under the long-constructed Indian Army Pokhran Test Range (IA-PTR) in the Thar Desert, eastern border of Pakistan. The Indian Meteorological Department and the Atomic Energy Commission announced the yield of the weapon at 12 kt. Other Western sources claimed the yield to be around 2–12 kt. However, the claim was dismissed by the Bulletin of the Atomic Scientists and it was later reported to be 8 kt.
 * May 11, 1998: Operation Shakti (type: implosion, 3 uranium and 2 plutonium devices, all underground). The Atomic Energy Commission (AEC) of India and the Defence Research and Development Organisation (DRDO) simultaneously conducted a test of three nuclear devices at the Indian Army Pokhran Test Range (IAPTR) on May 11, 1998. Two days later, on May 13, the AEC and DRDO carried out a test of two further nuclear devices, detonated simultaneously. During this operation, AEC India claimed to have tested a three-stage thermonuclear device (Teller-Ulam design), but the yield of the tests was significantly lower than that expected from thermonuclear devices. The yields remain questionable, at best, by Western and Indian scholars, estimated at 20kt-45kt.

Pakistan
Pakistan conducted 6 official tests, under 2 different code names, in the final week of May 1998. From 1983 to 1994, around 24 nuclear cold tests were carried out by Pakistan; these remained unannounced and classified until 2000. In May 1998, Pakistan responded publicly by testing 6 nuclear devices.


 * March 11, 1983,: Kirana-I (type: implosion, non-fissioned (plutonium) and underground). The 24 underground cold tests of nuclear devices were performed near the Sargodha Air Force Base. Due to serious political repercussions, Pakistan did not announce the results of the tests and even the yield of the first weapon remains classified. Because it was a cold test, the Pakistan Atomic Scientists Foundation (PASF) estimated the yield at no more than around 12–25 kilotonnes.


 * May 28, 1998: Chagai-I (type: implosion, HEU and underground). One underground horizontal-shaft tunnel test (inside a granite mountain) of boosted fission devices at Koh Kambaran in the Ras Koh Hills in Chagai District of Balochistan Province. The announced yield of the five devices was a total of 40–45 kilotonnes with the largest having a yield of approximately 30–45 kilotonnes. An independent assessment however put the test yield at no more than 12 kt and the maximum yield of a single device at only 9 kt as opposed to 35 kt as claimed by Pakistani authorities. According to The Bulletin of the Atomic Scientists, the maximum yield was only 2–10 kt as opposed to the claim of 35 kt and the total yield of all tests was no more than 8–15 kt.


 * May 30, 1998: Chagai-II (type: implosion, plutonium device and underground). One underground vertical-shaft tunnel test of a miniaturized fission device having an announced yield of approximately 18–20 kilotonnes, carried out in the Kharan Desert in Kharan District, Balochistan Province. An independent assessment put the figure of this test at 4–6 kt only. Some Western seismologists put the figure at a mere 2 kt.

North Korea
On October 9, 2006 North Korea announced they had conducted a nuclear test in North Hamgyong Province on the northeast coast at 10:36 AM (11:30 AEST). There was a 3.58 magnitude earthquake reported in South Korea. There was a 4.2 magnitude tremor detected 240 miles north of P'yongyang. The low estimates on the yield of the test—potentially less than a kiloton in strength—have led to speculation as to whether it was a fizzle (unsuccessful test), or not a genuine nuclear test at all.

On May 25, 2009, North Korea announced having conducted a second nuclear test. A tremor, with magnitude reports ranging from 4.7 to 5.3, was detected at Mantapsan, 233 miles northeast of P'yongyang and within a few kilometers of the 2006 test location. While estimates as to yield are still uncertain, with reports ranging from 3 to 20 kilotons, the stronger tremor indicates a significantly larger yield than the 2006 test.

On 12 February 2013, North Korean state media announced it had conducted an underground nuclear test, its third in seven years. A tremor that exhibited a nuclear bomb signature with an initial magnitude 4.9 (later revised to 5.1) was detected by both Comprehensive Nuclear-Test-Ban Treaty Organization Preparatory Commission (CTBTO) and the United States Geological Survey (USGS). The tremor occurred at 11:57 local time (02:57 UTC) and the USGS said the hypocenter of the event was only one kilometer deep. South Korea's defense ministry said the event reading indicated a blast of six to seven kilotons. However, there are some experts who estimate the yield to be up to 15 kt, since the test site's geology is not well understood. In comparison, the atomic (fission) bombs dropped by the Enola Gay on Hiroshima (Little Boy, a "gun-type" atomic bomb) and on Nagasaki by Bockscar (Fat Man, an "implosion-type" atomic bomb) had blast yields of the equivalents of 16 and 21 kilotons of TNT, respectively.

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.

Vela incident
In what is known as the Vela Incident, some country 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, or, if it was, who would have been responsible for it, although France, Israel or South Africa are sometimes named. The most widespread theory among those who believe that the flash was of nuclear origins was that it resulted from a joint South African and Israeli nuclear test. The topic remains highly disputed today.

Pakistan
Because Pakistan's nuclear programme was conducted under extreme secrecy, it raised concerns in the Soviet Union and India, who suspected that since the 1974 test it was inevitable that Pakistan would further develop its programme. The pro-Soviet newspaper, The Patriot, reported that "Pakistan has exploded a nuclear device in the range of 20 to 50 kilotons" in 1983. But it was widely dismissed by Western diplomats as it was pointed out that The Patriot had previously engaged in spreading disinformation on several occasions. In 1983, India and the Soviet Union both investigated secret tests but, due to lack of any scientific data, these statements were widely dismissed.

In their book, The Nuclear Express, authors Thomas Reed and Danny Stillman also allege that the People's Republic of China allowed Pakistan to detonate a nuclear weapon at its Lop Nur test site in 1990, eight years before Pakistan held its first official weapons test.

However, senior scientist Dr. Abdul Qadeer Khan strongly rejected the claim in May 1998. According to Khan, due to its sensitivity, no country allows another country to use their tests site to explode the devices. Such an agreement only existed between the United States and the United Kingdom since the 1958 US–UK Mutual Defense Agreement which among other things allows Britain access to the American Nevada National Security Site for testing. Dr. Samar Mubarakmand, another senior scientist, also confirmed Dr. Khan's statement and acknowledged that cold tests were carried out, under codename Kirana-I, in a test site which was built by the Corps of Engineers under the guidance of the PAEC.

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 that had nothing to do with the DPRK's nuclear weapons program.

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.

Tests of live warheads on rockets


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-2 missile with a live 600 kt W47 warhead was launched from the USS Ethan Allen; 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 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:
 * 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 I and had a yield of 3.75 Mt
 * Operation Argus: three tests, August 27, August 30, and September 6, 1958
 * 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 Dominic-Fishbowl series in 1962: Checkmate, Bluegill, Kingfish, and Tightrope

The Soviet Union tested nuclear explosives on rockets as part of their development of a localised anti-ballistic missile system in the 1960s. Some of the Soviet nuclear tests with warheads delivered by rocket include:
 * Operation Baikal (February 2, 1956, at Aralsk) - one test, with a R-5M rocket launch from Kapustin Yar.
 * Operation ZUR-215 (January 19, 1957, at Kapustin Yar) - one test, with a rocket launch from Kapustin Yar.
 * Operation Groza (September 6, 1961, at Kapustin Yar) - one test, with a rocket launch from Kapustin Yar.
 * Operation Grom (October 6, 1961, at Kapustin Yar) - one test, with a rocket launch from Kapustin Yar.
 * Operation Volga (September, 1961, at Novaya Zemlya) - two tests, with R-11M rockets launch from Rogachevo.
 * Operation Roza (September, 1961, at Novaya Zemlya) - two tests, with R-12 rockets launch from Vorkuta.
 * Raduga (October 20, 1961, at Novaya Zemlya) - one test, with a R-13 rocket launch.
 * Operation Tyulpan (September, 1962, at Novaya Zemlya) - probably two tests, with R-14 rockets launch from Chita.
 * Operation K (1961 and 1962, at Sary-Shagan) - five tests, with rockets launch from Kapustin Yar.

The People's Republic of China conducted a test with a Dongfeng-2 rocket launch in October 27, 1966. The warhead exploded with a yield of 12 kt.

List of most powerful nuclear tests
The following list contains all known nuclear tests conducted with a yield of 10 Mt TNT equivalent and more.