View source for Nuclear weapons testing

{{Short description|Controlled detonation of nuclear weapons for scientific or political purposes}}
[[File:Castle Bravo nuclear test (cropped).jpg|thumb|The [[mushroom cloud]] from the [[Castle Bravo]] [[thermonuclear weapon]] test in 1954, the largest nuclear weapons test ever conducted by the United States]]
{{Nuclear weapons}}
{{Weapons of mass destruction}}
'''Nuclear weapons tests''' are experiments carried out to determine the performance of [[nuclear weapon]]s and the effects of [[Nuclear explosion|their explosion]]. [[List of nuclear weapons tests|Over 2,000 nuclear weapons tests]] have been carried out since 1945. Nuclear testing is a sensitive political issue. Governments have often performed tests to signal strength. Because of their destruction and [[fallout]], testing has seen opposition by civilians as well as governments, with international bans having been agreed on. Thousands of tests have been performed, with most in the second half of the 20th century.

The first nuclear device was detonated as a test by the United States at the [[Trinity site]] in [[New Mexico]] on July 16, 1945, with a yield approximately [[TNT equivalent|equivalent]] to 20 [[kiloton]]s of [[TNT]]. The first [[thermonuclear weapon]] technology test of an engineered device, codenamed [[Ivy Mike]], was tested at the [[Enewetak Atoll]] in the [[Marshall Islands]] on November 1, 1952 (local date), also by the United States. The largest nuclear weapon ever tested was the [[Tsar Bomba]] of the [[Soviet Union]] at [[Novaya Zemlya]] on October 30, 1961, with the largest yield ever seen, an estimated 50–58 [[TNT equivalent|megatons]].

With the advent of nuclear technology and its increasingly global fallout an [[anti-nuclear movement]] formed and in 1963, three (UK, US, Soviet Union) of the then four nuclear states and many non-nuclear states signed the [[Limited Test Ban Treaty]], pledging to refrain from testing nuclear weapons in the atmosphere, underwater, or in [[outer space]]. The treaty permitted [[underground nuclear testing]]. [[France and weapons of mass destruction|France]] continued atmospheric testing until 1974, and [[China and weapons of mass destruction|China]] continued until 1980. Neither has signed the treaty.<ref>"The Treaty has not been signed by France or by the People's Republic of China." US Department of State, [https://2009-2017.state.gov/t/isn/4797.htm Limited Test Ban Treaty].</ref>

Underground tests conducted by the Soviet Union continued until 1990, the United Kingdom until 1991, the United States until 1992, and both China and France until 1996. In signing the [[Comprehensive Nuclear-Test-Ban Treaty]] in 1996, these countries pledged to discontinue all nuclear testing; the treaty has not yet entered into force because of its failure to be ratified by eight countries. Non-signatories [[India and weapons of mass destruction|India]] and [[Pakistan and weapons of mass destruction|Pakistan]] last tested nuclear weapons in 1998. [[North Korea]] conducted [[List of nuclear weapons tests of North Korea|nuclear tests]] in [[2006 North Korean nuclear test|2006]], [[2009 North Korean nuclear test|2009]], [[2013 North Korean nuclear test|2013]], [[January 2016 North Korean nuclear test|January 2016]], [[September 2016 North Korean nuclear test|September 2016]] and 2017. The [[2017 North Korean nuclear test|most recent confirmed nuclear test]] {{As of|2017|9|alt=occurred}} in September 2017 in North Korea.

==Types==
[[File:Types of nuclear testing.svg|thumb|Four major types of nuclear testing: 1. atmospheric, 2. [[underground nuclear testing|underground]], 3. exoatmospheric, and 4. underwater]]
Nuclear weapons tests have historically been divided into four categories reflecting the medium or location of the test.

*'''Atmospheric''' testing involves explosions that take place in the [[Atmosphere of Earth|atmosphere]]. Generally, these have occurred as devices detonated on [[Bomb tower|towers]], balloons, barges, or islands, or dropped from airplanes, and some only buried far enough to intentionally create a surface-breaking crater. The United States, the Soviet Union, and China have all conducted tests involving explosions of missile-launched warheads (See [[List of nuclear weapons tests#Tests of live warheads on rockets]]). Nuclear explosions close enough to the ground to draw dirt and debris into their [[mushroom cloud]] can generate large amounts of [[nuclear fallout]] due to [[irradiation]] of the debris (particularly with [[neutron radiation]]) as well as [[radioactive contamination]] of otherwise non-radioactive material. This definition of atmospheric is used in the [[Limited Test Ban Treaty]], which banned this class of testing along with exoatmospheric and underwater.
*'''Underground''' testing is conducted below the surface of the earth at varying depths. [[Underground nuclear testing]] comprised the majority of nuclear tests by the United States and the Soviet Union during the [[Cold War]]; other forms of nuclear testing were banned by the [[Limited Test Ban Treaty]] in 1963. True underground tests are intended to be fully contained and emit a negligible amount of fallout. These nuclear tests do occasionally "vent" to the surface, producing from nearly none to considerable amounts of radioactive debris as a consequence. Underground testing, almost by definition, causes [[seismic]] activity of a magnitude that depends on the [[nuclear weapon yield|yield]] of the nuclear device and the composition of the medium in which it is detonated, and generally creates a [[subsidence crater]].<ref>For a longer and more technical discussion, see {{cite book|title=The Containment of Underground Nuclear Explosions|url=http://www.nv.doe.gov/library/publications/historical/OTA-ISC-414.pdf|publisher=US Government Printing Office|date=October 1989|location=Washington, D.C.|author=US Congress, Office of Technology Assessment|access-date=2018-12-24|archive-url=https://web.archive.org/web/20130227180158/http://www.nv.doe.gov/library/publications/historical/OTA-ISC-414.pdf|archive-date=2013-02-27|url-status=dead}}</ref> In 1976, the United States and the USSR agreed to limit the maximum yield of underground tests to 150 [[kiloton|kt]] with the [[Threshold Test Ban Treaty]].<br />Underground testing also falls into two physical categories: tunnel tests in generally horizontal tunnel ''drifts'', and shaft tests in vertically drilled holes.
*'''Exoatmospheric''' testing is conducted above the atmosphere. The test devices are lifted on rockets. These [[high-altitude nuclear explosion]]s can generate a [[nuclear electromagnetic pulse]] (NEMP) when they occur in the [[ionosphere]], and charged particles resulting from the blast can cross hemispheres following [[magnetosphere|geomagnetic lines of force]] to create an auroral display.
*'''Underwater''' testing involves nuclear devices being [[Underwater explosion|detonated underwater]], usually moored to a ship or a barge (which is subsequently destroyed by the explosion). Tests of this nature have usually been conducted to evaluate the effects of nuclear weapons against naval vessels (such as in [[Operation Crossroads]]), or to evaluate potential sea-based nuclear weapons (such as [[nuclear torpedo]]es or [[nuclear depth charge|depth charges]]). Underwater tests close to the surface can disperse large amounts of radioactive particles in water and steam, contaminating nearby ships or structures, though they generally do not create fallout other than very locally to the explosion.

===Salvo tests===
Another way to classify nuclear tests is by the number of explosions that constitute the test.  The treaty definition of a salvo test is:

<blockquote>In conformity with treaties between the United States and the Soviet Union, a salvo is defined, for multiple explosions for peaceful purposes, as two or more separate explosions where a period of time between successive individual explosions does not exceed 5 seconds and where the burial points of all explosive devices can be connected by segments of straight lines, each of them connecting two burial points, and the total length does not exceed 40 kilometers. For nuclear weapon tests, a salvo is defined as two or more underground nuclear explosions conducted at a test site within an area delineated by a circle having a diameter of two kilometers and conducted within a total period of time of 0.1 seconds.<ref>{{cite web|title=Worldwide Nuclear Explosions| first1=Xiaoping| last1=Yang| first2=Robert| last2=North |first3=Carl| last3=Romney| first4=Paul R.| last4=Richards| url=http://www.ldeo.columbia.edu/~richards/my_papers/WW_nuclear_tests_IASPEI_HB.pdf}}</ref></blockquote>

The USSR has exploded up to eight devices in a single salvo test; Pakistan's second and last official test exploded four different devices.  Almost all lists in the literature are lists of tests; in the lists in Wikipedia (for example, ''[[Operation Cresset]]'' has separate items for ''Cremino'' and ''Caerphilly'', which together constitute a single test), the lists are of explosions.

==Purpose==
Separately from these designations, nuclear tests are also often categorized by the purpose of the test itself.

* '''Weapons-related''' tests are designed to garner information about how (and if) the weapons themselves work. Some serve to develop and validate a specific weapon type. Others test experimental concepts or are physics experiments meant to gain fundamental knowledge of the processes and materials involved in nuclear detonations.
* '''Weapons effects''' tests are designed to gain information about the effects of the weapons on structures, equipment, organisms, and the environment. They are mainly used to assess and improve survivability to nuclear explosions in civilian and military contexts, tailor weapons to their targets, and develop the tactics of nuclear warfare.
* '''Safety experiments''' are designed to study the behavior of weapons in simulated accident scenarios. In particular, they are used to verify that a (significant) nuclear detonation cannot happen by accident. They include one-point safety tests and simulations of storage and transportation accidents.
* '''Nuclear test detection experiments''' are designed to improve the capabilities to detect, locate, and identify nuclear detonations, in particular, to monitor compliance with test-ban treaties.  In the United States these tests are associated with Operation [[Vela Uniform]] before the [[Comprehensive Test Ban Treaty]] stopped all nuclear testing among signatories.
* '''[[Peaceful nuclear explosions]]''' were conducted to investigate non-military applications of nuclear explosives. In the United States, these were performed under the umbrella name of [[Operation Plowshare]].

Aside from these technical considerations, tests have been conducted for political and training purposes, and can often serve multiple purposes.

==Alternatives to full-scale testing==
[[File:NTS - LLNL subcritical experiment.jpg|thumb|upright|Subcritical experiment at the [[Nevada National Security Site]] ]]{{See also|Stockpile stewardship}}
Since the 1996 [[Comprehensive Nuclear-Test-Ban Treaty]], "nuclear explosions" of all kinds are banned. Nuclear nations have invested in many alternatives to maintain confidence in weapon capability:

* [[Computer simulation]] is used extensively to provide as much information as possible without physical testing. Mathematical models for such simulation model scenarios not only of performance but also of [[shelf life]] and [[maintenance]].<ref name="Scoles-2023-04-20">{{cite news |last1=Scoles |first1=Sarah |title=Trust but verify: U.S. labs are overhauling the nuclear stockpile. Can they validate the weapons without bomb tests? |url=https://www.science.org/content/article/trust-verify-can-u-s-certify-new-nuclear-weapons-without-detonating-them |work=Science |date=2023-04-20}}</ref><ref name="Hoffman-2011">{{cite news |last1=Hoffman |first1=David E. |title=Supercomputers offer tools for nuclear testing — and solving nuclear mysteries |url=https://www.washingtonpost.com/national/national-security/supercomputers-offer-tools-for-nuclear-testing--and-solving-nuclear-mysteries/2011/10/03/gIQAjnngdM_story.html |newspaper=Washington Post |date=2011-11-01}}</ref> A theme has generally been that even though simulations cannot fully replace physical testing, they can reduce the amount that is necessary.<ref name="AP-2006-10-18">{{cite news |last1=Associated Press |title=Supercomputers can't perfectly simulate nuclear blasts: Experts |url=https://www.cbc.ca/news/science/supercomputers-can-t-perfectly-simulate-nuclear-blasts-experts-1.597887 |work=CBC News |date=2006-10-18}}</ref>
* Physical testing
** Materials testing
*** Subcritical (or cold) tests involving fissile materials and [[high explosives]] that purposely result in no [[nuclear weapon yield|yield]]. The name refers to the lack of creation of a [[critical mass]] of fissile material. Subcritical tests continue to be performed by the United States, Russia, and the People's Republic of China, at least.<ref>{{cite web |date=2012-12-07 |title=US conducts 'subcritical' nuclear test |url=http://zeenews.india.com/news/world/us-conducts-subcritical-nuclear-test_815260.html |access-date=2013-05-28 |website=zeenews.india.com}}</ref><ref>{{cite web |author=Thomas Nilsen |date=2 October 2012 |title=Subcritical nuke tests may be resumed at Novaya Zemlya |url=http://barentsobserver.com/en/security/subcritical-nuke-tests-may-be-resumed-novaya-zemlya-02-10 |access-date=2017-07-13 |website=barentsobserver.com}}</ref> 
*** Proxy isotope testing: high temperature/density/pressure compression testing of non-fissile isotopes such as [[plutonium-242]] or [[uranium-238]], to determine a bomb core's relevant [[equation of state]].
** Fission testing
*** [[Critical mass]] experiments studying fissile material compositions, densities, geometries, and [[Neutron reflector|reflectors]]. They can be subcritical or supercritical, in which case significant radiation fluxes can be produced. This type of test has resulted in several [[criticality accident]]s.
*** Hydronuclear tests (hydrodynamical + nuclear) study nuclear materials under the conditions of explosive shock compression. They can create subcritical conditions, or supercritical conditions with yields ranging from negligible all the way up to a substantial fraction of full weapon yield.<ref>{{Citation |author=Carey Sublette |title=Nuclear Weapons Frequently Asked Questions |date=9 August 2001 |url=http://nuclearweaponarchive.org/Nwfaq/Nfaq4-1.html#Nfaq4.1.9 |access-date=10 April 2011 |at=section 4.1.9}}</ref> Any fission yield is considered banned by the CTBT.
** Fusion testing: [[inertial confinement fusion]] experiments using lasers, like the [[National Ignition Facility]], or magnetized liners, like the [[Z Pulsed Power Facility]], or projectile compression. These study the plasma physics and [[Fusion ignition|ignition]] of deuterium-tritium mixtures. 

Subcritical tests executed by the United States include:<ref>{{cite journal|last1=Papazian|first1=Ghazar R.|last2=Reinovsky|first2=Robert E.|last3=Beatty|first3=Jerry N.|url=https://fas.org/sgp/othergov/doe/lanl/pubs/las28/papazian.pdf|access-date=2013-12-12|title=The New World of the Nevada Test Site|journal=Los Alamos Science|issue=28|year=2003}}</ref><ref>{{cite journal|last1=Thorn|first1=Robert N.|first2=Donald R.|last2=Westervelt|date=February 1, 1987|title=Hydronuclear Experiments|journal=LANL Report LA-10902-MS|url=https://fas.org/sgp/othergov/doe/lanl/docs1/00090266.pdf|access-date=December 9, 2013}}</ref><ref>{{cite journal |last=Conrad |first=David C. |date=July 1, 2000 |title=Underground explosions are music to their ears |journal=Science and Technology Review |url=http://www.llnl.gov/str/Conrad.html |access-date=9 December 2013}}</ref>

{| class="wikitable sortable"
 |+Subcritical Tests
 |-
 !style="background:#efefef;" | Name
 !style="background:#efdead;" | Date Time ([[Universal Time|UT]]{{efn|Universal Time at the [[Nevada National Security Site]] is 8 hours after local time; UT dates are one day after local date for UT times after 16:00.}})
 !style="background:#efefef;" | Location
 !style="background:#efdead;" | Elevation + Height
 !style="background:#efefef;" | Notes
 |-
 ! A series of 50 tests
 | {{dts|1960-1-1}} 
 | [[Los Alamos National Lab]] Test Area 49 {{coord|35.82289|-106.30216|display=inline}}
 | {{sort|002163|}}{{convert|2183|m}} and {{convert|20|m}}
 | Series of 50 tests during US/USSR joint nuclear test ban.<ref>{{Cite report |title=Nevada Test Site: U1a Complex subcritical experiments |url=http://www.nv.doe.gov/news&pubs/dirpdfs/DOENV708_REV1_U1a.pdf |archive-url=https://web.archive.org/web/20030517214406/http://www.nv.doe.gov/news&pubs/dirpdfs/DOENV708_REV1_U1a.pdf |archive-date=17 May 2003 |url-status=dead |publisher=DOE Nevada |date=February 2003 }}</ref>
 |-
 ! ''Odyssey''
 | {{dts|}} 
 | [[Nevada National Security Site|NTS]] Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|001032|}}{{convert|1222|m}} and {{convert|190|m}}
 |
 |-
 ! ''Trumpet''
 | {{dts|}} 
 | NTS Area U1a-102D {{coord|37.01099|-116.05848|display=inline}}
 | {{sort|001032|}}{{convert|1222|m}} and {{convert|190|m}}
 |
 |-
 ! ''Kismet''
 | {{dts|1995-03-01}} 
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|000929|}}{{convert|1222|m}} and {{convert|293|m}}
 | Kismet was a proof of concept for modern hydronuclear tests; it did not contain any SNM (Special Nuclear Material—plutonium or uranium).
 |-
 ! ''Rebound''
 | {{dts|1997-07-02}} 10:—:—
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|000929|}}{{convert|1222|m}} and {{convert|293|m}}
 | Provided information on the behavior of new plutonium alloys compressed by high-pressure shock waves; same as Stagecoach but for the age of the alloys.
 |-
 ! ''Holog''
 | {{dts|1997-09-18}} 
 | NTS Area U1a.101A {{coord|37.01036|-116.05888|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | Holog and Clarinet may have switched locations.
 |-
 ! ''Stagecoach''
 | {{dts|1998-03-25}} 
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | Provided information on the behavior of aged (up to 40 years) plutonium alloys compressed by high-pressure shock waves.
 |-
 ! ''Bagpipe''
 | {{dts|1998-09-26}} 
 | NTS Area U1a.101B {{coord|37.01021|-116.05886|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | 
 |-
 ! ''Cimarron''
 | {{dts|1998-12-11}} 
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | Plutonium surface ejecta studies.
 |-
 ! ''Clarinet''
 | {{dts|1999-02-09}} 
 | NTS Area U1a.101C {{coord|37.01003|-116.05898|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | Holog and Clarinet may have switched places on the map.
 |-
 ! ''Oboe''
 | {{dts|1999-09-30}} 
 | NTS Area U1a.102C {{coord|37.01095|-116.05877|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | 
 |-
 ! ''Oboe 2''
 | {{dts|1999-11-09}} 
 | NTS Area U1a.102C {{coord|37.01095|-116.05877|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | 
 |-
 ! ''Oboe 3''
 | {{dts|2000-02-03}} 
 | NTS Area U1a.102C {{coord|37.01095|-116.05877|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | 
 |-
 ! ''Thoroughbred''
 | {{dts|2000-03-22}} 
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | Plutonium surface ejecta studies, followup to Cimarron.
 |-
 ! ''Oboe 4''
 | {{dts|2000-04-06}} 
 | NTS Area U1a.102C {{coord|37.01095|-116.05877|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | 
 |-
 ! ''Oboe 5''
 | {{dts|2000-08-18}} 
 | NTS Area U1a.102C {{coord|37.01095|-116.05877|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | 
 |-
 ! ''Oboe 6''
 | {{dts|2000-12-14}} 
 | NTS Area U1a.102C {{coord|37.01095|-116.05877|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | 
 |-
 ! ''Oboe 8''
 | {{dts|2001-09-26}} 
 | NTS Area U1a.102C {{coord|37.01095|-116.05877|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | 
 |-
 ! ''Oboe 7''
 | {{dts|2001-12-13}} 
 | NTS Area U1a.102C {{coord|37.01095|-116.05877|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | 
 |-
 ! ''Oboe 9''
 | {{dts|2002-06-07}} 21:46:—
 | NTS Area U1a.102C {{coord|37.01095|-116.05877|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | 
 |-
 ! ''Mario''
 | {{dts|2002-08-29}} 19:00:—
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | Plutonium surface studies (optical analysis of spall). Used wrought plutonium from Rocky Flats.
 |-
 ! ''Rocco''
 | {{dts|2002-09-26}} 19:00:—
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | Plutonium surface studies (optical analysis of spall), followup to Mario. Used cast plutonium from Los Alamos.
 |-
 ! ''Piano''
 | {{dts|2003-09-19}} 20:44:—
 | NTS Area U1a.102C {{coord|37.01095|-116.05877|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | 
 |-
 ! ''Armando''
 | {{dts|2004-05-25}} 
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|000932|}}{{convert|1222|m}} and {{convert|290|m}}
 | Plutonium spall measurements using x-ray analysis.{{efn|{{YouTube|EFUUE5shMLc|A video of the ''Armando'' test}}}}
 |-
 ! ''Step Wedge''
 | {{dts|2005-04-01}} 
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|001032|}}{{convert|1222|m}} and {{convert|190|m}}
 | April–May 2005, a series of mini-hydronuclear experiments interpreting Armando results.
 |-
 ! ''Unicorn''
 | {{dts|2006-08-31}} 01:00:—
 | NTS Area U6c {{coord|36.98663|-116.0439|display=inline}}
 | {{sort|001032|}}{{convert|1222|m}} and {{convert|190|m}}
 | "...confirm nuclear performance of the W88 warhead with a newly-manufactured pit."  Early pit studies.
 |-
 ! ''Thermos''
 | {{dts|2007-01-01}} 
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|001032|}}{{convert|1222|m}} and {{convert|190|m}}
 | February 6 – May 3, 2007, 12 mini-hydronuclear experiments in thermos-sized flasks.
 |-
 ! ''Bacchus''
 | {{dts|2010-09-16}} 
 | NTS Area U1a.05? {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|001032|}}{{convert|1222|m}} and {{convert|190|m}}
 | 
 |-
 ! ''Barolo A''
 | {{dts|2010-12-01}} 
 | NTS Area U1a.05? {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|001032|}}{{convert|1222|m}} and {{convert|190|m}}
 | 
 |-
 ! ''Barolo B''
 | {{dts|2011-02-02}} 
 | NTS Area U1a.05? {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|001032|}}{{convert|1222|m}} and {{convert|190|m}}
 | 
 |-
 ! ''Castor''
 | {{dts|2012-09-01}} 
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|001032|}}{{convert|1222|m}} and {{convert|190|m}}
 | Not even a subcritical, contained no plutonium; a dress rehearsal for Pollux.
 |-
 ! ''Pollux''
 | {{dts|2012-12-05}} 
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|001032|}}{{convert|1222|m}} and {{convert|190|m}}
 | A subcritical test with a scaled-down warhead mockup.{{efn|{{YouTube|bGf4-ZOjyVY|A video of the ''Pollux'' test|link=no}}}}
 |-
 ! ''Leda''
 | {{dts|2014-06-15}} 
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|001032|}}{{convert|1222|m}} and {{convert|190|m}}
 | Like ''Castor'', the plutonium was replaced by a surrogate; this is a dress rehearsal for the later ''Lydia''.  The target was a weapons pit mock-up.{{efn|{{YouTube|vmsfgRtxbHg|A video of the ''Leda'' test|link=no}}}}
 |-
 ! ''Lydia''
 | {{dts|2015-01-01|format=hide}}??-??-2015
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | {{sort|001032|}}{{convert|1222|m}} and {{convert|190|m}}
 | Expected to be a plutonium subcritical test with a scaled-down warhead mockup.{{citation needed|date=April 2017}}
 |-
 ! ''Vega''
 | {{dts|2017-12-13}}
 | Nevada test site
 | 
 | Plutonium subcritical test with a scaled down warhead mockup.<ref>{{Cite web |first=Andrew |last=Kishner |date=18 September 2018 |title=U.S. Sneaks in 'Vega,' Its 28th Subcritical Nuclear Test |url=http://andrewkishner.com/vega.htm |access-date=30 October 2019}}</ref>
 |-
 ! ''Ediza''
 | {{dts|2019-02-13}}
 | NTS Area U1a {{coord|37.01139|-116.05983|display=inline}}
 | 
 | Plutonium subcritical test designed to confirm supercomputer simulations for stockpile safety.<ref>{{cite web |last=O'Brien |first=Nolan |url=https://www.llnl.gov/news/subcritical-experiment-captures-scientific-measurements-advance-stockpile-safety |title=Subcritical experiment captures scientific measurements to advance stockpile safety |work=[[Lawrence Livermore National Laboratory|LLNL]] |date=24 May 2019 |access-date=16 January 2021}}</ref>
 |-
 ! ''Nightshade A''
 | {{dts|2020-11}}
 | Nevada test site
 | 
 | Plutonium subcritical test designed to measure ejecta emission.<ref>{{cite web |url=https://www3.nhk.or.jp/nhkworld/en/news/20210116_12/ |title=US conducted subcritical nuclear test in November |work=[[NHK World-Japan]] |date=16 January 2021 |access-date=16 January 2021}}</ref><ref>{{cite report |last1=Danielson |first1=Jeremy |last2=Bauer |first2=Amy L. |title=Nightshade Prototype Experiments (Silverleaf) |work=[[Los Alamos National Laboratory]] |publisher=[[Office of Scientific and Technical Information|OSTI]] |date=September 2016 |doi=10.2172/1338708|osti=1338708 |doi-access=free }}</ref>
 |}

==History==
{{Main|Timeline of nuclear weapons development}}
[[File:Phoenix en route to North Vietnam, 1967.jpg|thumb|right|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.]] 
[[File:Wfm sts overview.png|thumb|The {{convert|18000|km2||adj=on|order=flip}} expanse of the [[Semipalatinsk Test Site]] (indicated in red), attached to [[Kurchatov, Kazakhstan|Kurchatov]] (along the [[Irtysh river]]). The site comprised an area [[the size of Wales]].<ref>{{cite web |url=http://www.thebulletin.org/web-edition/features/the-lasting-toll-of-semipalatinsks-nuclear-testing |title=The lasting toll of Semipalatinsk's nuclear testing |author=Togzhan Kassenova |date=28 September 2009 |work=Bulletin of the Atomic Scientists }}</ref>]]
{| class="wikitable sortable mw-collapsible"
|+Notable nuclear explosions
!Significance
!Country
!Name
!Date
!Yield
|-
|First plutonium test
| rowspan="2" |{{Flag|United States|1912}}
| rowspan="2" |[[Trinity (nuclear test)|Trinity]]
| rowspan="2" |July 16, 1945
| rowspan="2" |25 kt
|-
|First implosion test
|-
|First uranium bomb
| rowspan="2" |{{Flag|United States|1912}}
| rowspan="2" |[[Atomic bombings of Hiroshima and Nagasaki|Atomic bombing of Hiroshima]]
| rowspan="2" |August 6, 1945
| rowspan="2" |15 kt
|-
|First gun-type bomb
|-
|First underwater test
|{{Flag|United States|1912}}
|[[Operation Crossroads#Test Baker|Crossroads ''Baker'']]
|July 16, 1946
|23 kt
|-
|First [[Thermonuclear weapon|thermonuclear]] test
|{{Flag|United States|1912}}
|[[Greenhouse George|Greenhouse ''George'']]
|May 8, 1951
|225 kt
|-
|First [[fusion boosting]]
|{{Flag|United States|1912}}
|[[Greenhouse Item|Greenhouse ''Item'']]
|May 25, 1951
|45.5 kt
|-
|First underground test
|{{Flag|United States|1912}}
|[[Operation Buster–Jangle|Buster–Jangle ''Uncle'']]
|November 29, 1951
|1.2 kt
|-
|First multi-megaton test
| rowspan="2" |{{Flag|United States|1912}}
| rowspan="2" |[[Ivy Mike|Ivy ''Mike'']]
| rowspan="2" |November 1, 1952
| rowspan="2" |10.4 Mt
|-
|First cryogenic deuterium test
|-
|First [[Layer cake design|layer-cake]] test
| rowspan="2" |{{Flag|Soviet Union}}
| rowspan="2" |[[RDS-6s]]
| rowspan="2" |August 12, 1953
| rowspan="2" |400 kt
|-
|First solid-fuelled thermonuclear test
|-
|First [[High-altitude nuclear explosion|exoatmospheric test]]
|{{Flag|United States|1912}}
|[[Operation Argus|Argus I]]
|August 27, 1958
|1.7 kt
|-
|Largest test
|{{Flag|Soviet Union}}
|[[Tsar Bomba]]
|October 31, 1961
|50 Mt
|-
|Largest exoatmospheric test
|{{Flag|United States|1912}}
|[[Starfish Prime|Fishbowl ''Starfish Prime'']]
|July 9, 1962
|1.4 Mt
|-
|Largest underground test
|{{Flag|United States|1912}}
|[[Cannikin|Grommet ''Cannikin'']]
|November 6, 1971
|5 Mt
|-
|Most recent atmospheric test
|{{Flag|China}}
|[[List of nuclear weapons tests of China|1980 Chinese nuclear test]]
|October 16, 1980
|1 Mt
|-
|Most recent test
|{{Flag|North Korea}}
|[[2017 North Korean nuclear test]]
|September 3, 2017
|50-300 kt
|}
The first atomic weapons test was conducted near Alamogordo, New Mexico, on July 16, 1945, during the [[Manhattan Project]], and given the codename "[[Trinity test|Trinity]]". The test was originally to confirm that the implosion-type [[nuclear weapon design]] was feasible, and to give an idea of what the actual size and effects of a [[Effects of nuclear explosions|nuclear explosion]] would be before it was used in combat against Japan. The test gave a good approximation of many of the explosion's effects, but did not give an appreciable understanding of [[nuclear fallout]], which was not well understood by the project scientists until after the [[atomic bombings of Hiroshima and Nagasaki]].

The United States conducted six atomic tests before the Soviet Union developed its first atomic bomb ([[RDS-1]]) and tested it on August 29, 1949. Neither country had many atomic weapons to spare at first, and testing was relatively infrequent. (When the US used two weapons for ''[[Operation Crossroads]]'' in 1946, they were detonating over 20% of their current arsenal.) By the 1950s the United States had established a dedicated test site on its own territory ([[Nevada Test Site]]) and was also using a site in the [[Marshall Islands]] ([[Pacific Proving Grounds]]) for extensive atomic and nuclear testing.

The early tests were used primarily to discern the military effects of atomic weapons (''Crossroads'' had involved the effect of atomic weapons on a navy, and how they functioned underwater) and to test new weapon designs. During the 1950s, these included new hydrogen bomb designs, which were tested in the Pacific, and also new and improved fission weapon designs. The Soviet Union also began testing on a limited scale, primarily in [[Kazakhstan]]. During the later phases of the [[Cold War]], both countries developed accelerated testing programs, testing many hundreds of bombs over the last half of the 20th century.

[[File:Bravo fallout2.png|left|thumb|In 1954 the [[Castle Bravo]] fallout plume spread dangerous levels of radiation over an area over {{convert|100|mi|||}} long, including inhabited islands.]]

Atomic and nuclear tests can involve many hazards. Some of these were illustrated in the US [[Castle Bravo]] test in 1954. The weapon design tested was a new form of hydrogen bomb, and the scientists underestimated how vigorously some of the weapon materials would react. As a result, the explosion, with a [[nuclear weapons yield|yield]] of 15 [[TNT equivalent|Mt]],was over twice what was predicted. The weapon also generated a large amount of radioactive [[nuclear fallout]], more than had been anticipated, and a change in the weather pattern caused the fallout to spread in a direction not cleared in advance. The fallout plume spread high levels of radiation for over {{convert|100|mi|||}}, contaminating populated islands in nearby atoll formations. Though they were soon evacuated, many of the islands' inhabitants suffered from radiation burns and later from other effects such as increased cancer rate and birth defects, as did the crew of the Japanese fishing boat ''[[Daigo Fukuryū Maru]]''. One crewman died from radiation sickness after returning to port, and it was feared that the radioactive fish they had been carrying may have entered the Japanese food supply.

[[File:US fallout exposure.png|right|thumb|Because of concerns about worldwide fallout levels, the [[Partial Test Ban Treaty]] was signed in 1963. Above are the per capita [[thyroid]] doses (in [[Rad (unit)|rads]]) in the continental United States resulting from all exposure routes from all atmospheric nuclear tests conducted at the [[Nevada Test Site]] from 1951 to 1962.]]

Castle Bravo was the worst US nuclear accident, but many of its component problems—unpredictably large yields, changing weather patterns, unexpected fallout [[radioactive contamination|contamination]] of populations and the food supply—also occurred during atmospheric nuclear weapons tests by other countries. Concerns over worldwide fallout rates eventually led to the [[Partial Test Ban Treaty]] in 1963, which limited signatories to underground testing. Not all countries ceased atmospheric testing, but because the United States and the Soviet Union were responsible for roughly 86% of all nuclear tests, their compliance cut the overall level substantially. France continued atmospheric testing until 1974, and China until 1980.

A tacit moratorium on testing was in effect from 1958 to 1961 and ended with a series of Soviet tests in late 1961, including the [[Tsar Bomba]], the largest nuclear weapon ever tested. The United States responded in 1962 with [[Operation Dominic]], involving dozens of tests including the explosion of a missile launched from a submarine.

Almost all new nuclear powers have announced their possession of nuclear weapons with a nuclear test. The only acknowledged nuclear power that claims never to have conducted a test is South Africa (although see [[Vela incident]]), which has since dismantled all of its weapons. Israel is widely thought to possess a sizeable nuclear arsenal though it has never tested, unless they were involved in Vela. Experts disagree on whether states can have reliable nuclear arsenals, especially ones using advanced warhead designs, such as hydrogen bombs and miniaturized weapons, without testing, although all agree that it is unlikely that significant nuclear innovations can be developed without testing. One other approach is to use [[supercomputer]]s to conduct "virtual" testing, but codes need to be validated against test data.

There have been many attempts to limit the number and size of nuclear tests; the most far-reaching was the [[Comprehensive Test Ban Treaty]] of 1996, which, {{as of|2013|lc=y}}, had not been ratified by eight of the "[[Comprehensive Test Ban Treaty#Status|Annex 2 countries]]" required for it to take effect, including the United States. Nuclear testing became a controversial issue in the United States, with a number of politicians saying that future testing might be necessary to maintain the ageing warheads from the [[Cold War]]. Nuclear testing is seen as furthering nuclear arms development, and many are opposed to future testing as an acceleration of the arms race.

In [[List of nuclear weapons tests|total nuclear test megatonnage]], from 1945 to 1992, 520 atmospheric nuclear explosions (including eight underwater) were conducted with a total yield of 545 [[TNT equivalent|megaton]]s,<ref name="auto">{{cite book|title=Atmospheric Nuclear Tests|first=O. A.|last=Pavlovski|date=1 January 1998|publisher=Springer, Berlin, Heidelberg|pages=219–260|doi=10.1007/978-3-662-03610-5_17|chapter = Radiological Consequences of Nuclear Testing for the Population of the Former USSR (Input Information, Models, Dose, and Risk Estimates)|isbn = 978-3-642-08359-4}}</ref> with a peak occurring in 1961–1962, when 340 megatons were detonated in the atmosphere by the United States and [[Soviet Union]].<ref>{{cite web|url=http://www.atomicarchive.com/Docs/Effects/wenw_chp2.shtml|title=Radioactive Fallout - Worldwide Effects of Nuclear War - Historical Documents |website=Atomciarchive.com}}</ref> The estimated number of underground nuclear tests conducted in the period from 1957 to 1992 was 1,352 explosions with a total yield of 90 Mt.<ref name="auto"/>

<gallery mode=packed heights=180>
Image: Trinity shot color.jpg|The first atomic test, "[[Trinity test|Trinity]]", took place on July 16, 1945.
Image: Sedan Plowshare Crater.jpg|The [[Sedan (nuclear test)|Sedan]] test of 1962 was an experiment by the United States in using nuclear weapons to excavate large amounts of earth.
File:330-PS-3256 (45898 AC) (17204655228).jpg|[[Kytoon]] balloons were used on Indian Springs Air Force Base, Nevada, April 20, 1952, to get exact weather information during atomic test periods.
</gallery>

==Yield==
The [[Nuclear weapon yield|yield]] of atomic and thermonuclear weapons is typically measured in kilotons or megatons [[TNT equivalent]]. Thermonuclear (fusion/fission by [[Teller-Ulam design]]) bombs, often mesaured in megatons, can be hundreds of times stronger than their atomic (fission only) counterparts measured only in kilotons. 

In the US context, it was decided during the Manhattan Project that yield measured in tons of TNT equivalent could be imprecise. This comes from the range of experimental values of the energy content of TNT, ranging from {{convert|900|to|1100|cal/g}}. There was also the issue of which ton to use, as short tons, long tons, and metric tonnes all had different values. It was decided that one kiloton would be equivalent to {{convert|1e12|cal}} exactly,<ref name="contain">{{cite report |date=31 October 1989 |title=The Containment of Underground Explosions |url=https://www.osti.gov/opennet/detail?osti-id=16383760 |publisher=Office of Technology Assessment |page=11 |docket=OTA-ISC-414 |access-date= |quote=}}</ref> (the equivalent of 1000 cal/g if the metric tonne were used).

==Nuclear testing by country==
{{main|List of nuclear weapons tests}}
[[File:Rael Nuclear use locations world map.png|thumb|Over 2,000 nuclear tests have been conducted in over a dozen different sites around the world. Red Russia/Soviet Union, blue France, light blue United States, violet Britain, yellow China, orange India, brown Pakistan, green North Korea, and light green (territories exposed to nuclear bombs). The black dot indicates the location of the [[Vela incident]].]]
[[File:Operation Crossroads Baker Edit.jpg|thumb|"Baker Shot", part of [[Operation Crossroads]], a nuclear test by the United States at [[Bikini Atoll]] in 1946]]

The nuclear powers have conducted more than 2,000 nuclear test explosions (numbers are approximate, as some test results have been disputed):

* {{flagicon|USA}} '''United States''': 1,054 tests by official count (involving at least 1,149 devices). 219 were atmospheric tests as defined by the [[Comprehensive Test Ban Treaty|CTBT]]. These tests include 904 at the [[Nevada Test Site]], 106 at the [[Pacific Proving Grounds]] and other locations in the Pacific, 3 in the South Atlantic Ocean, and 17 other tests taking place in [[Amchitka]] [[Alaska]], [[Colorado]], [[Mississippi]], [[New Mexico]] and [[Nevada]] outside the NNSS (see [[Nuclear weapons and the United States]] for details). 24 tests are classified as British tests held at the NTS. There were 35 Plowshare detonations and 7 Vela Uniform tests; 88 tests were safety experiments and 4 were transportation/storage tests.<ref>{{cite web|publisher=Department of Energy, Nevada Operations Office|date=2000-12-01|title=United States Nuclear Tests: July 1945 through September 1992|location=Las Vegas, NV|url=http://www.nv.doe.gov/library/publications/historical/DOENV_209_REV15.pdf|access-date=2013-12-18|url-status=dead|archive-url=https://web.archive.org/web/20061012160826/http://www.nv.doe.gov/library/publications/historical/DOENV_209_REV15.pdf|archive-date=2006-10-12}} This is usually cited as the "official" US list.</ref> Motion pictures were made of the explosions, later used to validate computer simulation predictions of explosions.<ref>{{Cite news|url=https://www.scientificamerican.com/article/blasts-from-the-past-old-nuke-test-films-offer-new-insights-video|title=Blasts from the Past: Old Nuke Test Films Offer New Insights [Video]|last=Long|first=Kat|work=Scientific American|access-date=2017-04-24}}</ref> ''[[Nuclear weapons and the United States|United States' table data]]''.
* {{flagicon|USSR}} '''Soviet Union''': 715 tests (involving 969 devices) by official count, plus 13 unnumbered test failures.<ref>{{cite document|publisher=RFNC-VNIIEF|year=1996|title=USSR Nuclear Weapons Tests and Peaceful Nuclear Explosions 1949 through 1990|location=Sarov, Russia}} The official Russian list of Soviet tests.</ref><ref>{{cite web|last1=Mikhailov, Editor in Chief|first1=V.N.|first2=L.A.|last2=Andryushin|first3=N.P.|last3=Voloshin|first4=R.I.|last4=Ilkaev|first5=A.M.|last5=Matushchenko|first6=L.D.|last6=Ryabev|first7=V.G.|last7=Strukov|first8=A.K.|last8=Chernyshev|first9=Yu.A.|last9=Yudin|title=Catalog of Worldwide Nuclear Testing|url=http://www.iss-atom.ru/ksenia/catal_nt/|access-date=2013-12-28|url-status=dead|archive-url=https://web.archive.org/web/20131219131618/http://www.iss-atom.ru/ksenia/catal_nt/|archive-date=2013-12-19}}An equivalent list available on the internet.</ref> Most were at their Southern Test Area at [[Semipalatinsk Test Site]] and the Northern Test Area at [[Novaya Zemlya]].  Others include rocket tests and peaceful-use explosions at various sites in [[Russia]], [[Kazakhstan]], [[Turkmenistan]], [[Uzbekistan]] and [[Ukraine]]. ''[[List of nuclear weapons tests of the Soviet Union|Soviet Union's table data]]''.
* {{flagicon|UK}} '''United Kingdom''': 45 tests, of which 12 were in [[Australia]]n territory, including three at the [[Montebello Islands]] and nine in mainland [[South Australia]] at [[British nuclear tests at Maralinga|Maralinga]] and Emu Field,<ref>{{Cite web| title = British nuclear weapons testing in Australia {{!}} ARPANSA| accessdate = 2022-11-02| url = https://www.arpansa.gov.au/understanding-radiation/sources-radiation/more-radiation-sources/british-nuclear-weapons-testing}}</ref>  9 at [[Kiritimati|Christmas Island (Kiritimati)]] in the [[Pacific Ocean]], plus 24 in the United States at the Nevada Test Site [[1958 US–UK Mutual Defence Agreement|as part of joint test series]]).<ref>{{cite web|url=http://www.awe.co.uk/main_site/about_awe/history/timeline/1958/index.html  |title=UK/US Agreement |access-date=2010-10-21 |archive-url = https://web.archive.org/web/20070607112924/http://www.awe.co.uk/main_site/about_awe/history/timeline/1958/index.html |archive-date = 2007-06-07}}</ref> 43 safety tests (the ''Vixen'' series) are not included in that number, though safety experiments by other countries are. ''[[Nuclear weapons and the United Kingdom|The United Kingdom's summary table]]''.
* {{flagicon|France}} '''France''': 210 tests by official count (50 atmospheric, 160 underground<ref>{{cite web|url=http://www.assemblee-nationale.fr/rap-oecst/essais_nucleaires/i3571.asp |title=N° 3571.- Rapport de MM. Christian Bataille et Henri Revol sur les incidences environnementales et sanitaires des essais nucléaires effectués par la France entre 1960 et 1996 (Office d'évaluation des choix scientifiques et technologiques) |website=Assemblee-nationale.fr |access-date=2010-10-21}}</ref>), four atomic atmospheric tests at [[C.S.E.M.]] near [[Reggane]], 13 atomic underground tests at [[C.E.M.O.]] near [[In Ekker]] in the French [[Algeria]]n [[Sahara]], and nuclear atmospheric and underground tests at and around [[Fangataufa]] and [[Moruroa]] Atolls in [[French Polynesia]]. Four of the In Ekker tests are counted as peaceful use, as they were reported as part of the CET's APEX (Application pacifique des expérimentations nucléaires, “Peaceful Application of Nuclear Experiments”), and given alternate names. ''[[France and weapons of mass destruction|France's summary table]]''.
* {{flagicon|China}} '''China''': 45 tests (23 atmospheric and 22 underground), at [[Lop Nur]] Nuclear Weapons Test Base, in [[Malan, Xinjiang|Malan]], [[Xinjiang]]<ref>{{cite web|url=https://fas.org/nuke/guide/china/nuke/index.html|title=Nuclear Weapons Test List|website=Fas.org|access-date=22 September 2018}}</ref> There are two additional unnumbered failed tests. ''[[China's nuclear test series|China's summary table]]''.
* {{flagicon|India}} '''India''': Six underground explosions (including the first one in 1974), at [[Pokhran]]. ''[[India's nuclear testing series|India's summary table]]''.
* {{flagicon|Pakistan}} '''Pakistan''': Six underground explosions at [[Ras Koh Hills]] and the [[Chagai District]].<ref>{{Cite web |url=https://fas.org/nuke/guide/pakistan/nuke/chron.htm |title=Pakistan Special Weapons - A Chronology |access-date=2018-12-24 |archive-url=https://web.archive.org/web/20120427000543/http://www.fas.org/nuke/guide/pakistan/nuke/chron.htm |archive-date=2012-04-27 |url-status=dead }}</ref> ''[[Pakistan's nuclear testing series|Pakistan's summary table]]''.
* {{flagicon|North Korea}} '''North Korea''': North Korea is the only country in the world that still tests nuclear weapons, and their tests have caused [[2017-2018 North Korea crisis|escalating tensions between them and the United States]]. Their most recent nuclear test was on [[2017 North Korean nuclear test|September 3, 2017]]. ''[[North Korea's nuclear testing series|North Korea's summary table]]''
 
There may also have been at least three alleged but unacknowledged nuclear explosions (see [[List of nuclear tests#Alleged tests|list of alleged nuclear tests]]) including the [[Vela incident]].

From the first nuclear test in 1945 until tests by Pakistan in 1998, there was never a period of more than 22 months with no nuclear testing. June 1998 to October 2006 was the longest period since 1945 with no acknowledged nuclear tests.

A summary table of all the nuclear testing that has happened since 1945 is here: [[Worldwide nuclear testing counts and summary]].

[[File:Worldwide nuclear testing multilang.svg|750px|center|Graph of nuclear testing|lang=en]]

== Global fallout ==
{{main|Nuclear fallout#Global fallout}}
[[File:Radiocarbon bomb spike.svg|thumb|Atmospheric <sup>14</sup>C [[Bomb pulse]], [[New Zealand]]<ref>{{cite journal|url=http://cdiac.esd.ornl.gov/trends/co2/welling.html |title=Atmospheric δ<sup>14</sup>C record from Wellington |access-date=2007-06-11 |journal=Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center |year=1994 |url-status=dead |archive-url=https://web.archive.org/web/20140201222225/http://cdiac.esd.ornl.gov/trends/co2/welling.html |archive-date=1 February 2014 }}</ref> and [[Austria]].<ref>{{cite journal| url=http://cdiac.esd.ornl.gov/trends/co2/cent-verm.html| author=Levin, I.| title=δ<sup>14</sup>C record from Vermunt| journal=Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center| year=1994| display-authors=etal| access-date=4 January 2016| archive-url=https://web.archive.org/web/20080923105819/http://cdiac.esd.ornl.gov/trends/co2/cent-verm.html| archive-date=23 September 2008| url-status=dead}}</ref> The New Zealand curve is representative for the Southern Hemisphere, the Austrian curve is representative for the Northern Hemisphere. Atmospheric nuclear weapon tests almost doubled the concentration of <sup>14</sup>C in the Northern Hemisphere.<ref>{{cite web | url=http://www1.phys.uu.nl/ams/Radiocarbon.htm | publisher=University of Utrecht | title= Radiocarbon dating | access-date=2008-02-19}}</ref>]]
Nuclear weapons testing did not produce an outcome like [[nuclear winter]] as a result of a scenario of a concentrated number of nuclear explosions in a [[nuclear holocaust]], but the thousands of tests, hundreds being atmospheric, did produce a global fallout that peaked in 1963 (the [[bomb pulse]]), reaching levels of about 0.15&nbsp;[[mSv]] per year worldwide, or about 7% of average [[background radiation]] dose from all sources. It has slowly decreased since,<ref name="t904">{{cite journal | last1=Bouville | first1=André | last2=Simon | first2=Steven L. | last3=Miller | first3=Charles W. | last4=Beck | first4=Harold L. | last5=Anspaugh | first5=Lynn R. | last6=Bennett | first6=Burton G. | title=Estimates of Doses from Global Fallout | journal=Health Physics | volume=82 | issue=5 | date=2002 | issn=0017-9078 | doi=10.1097/00004032-200205000-00015 | pages=690–705| pmid=12003019 | bibcode=2002HeaPh..82..690B }}</ref> with natural environmental radiation levels being around 1 [[mSv]]. This global fallout was one of the main drivers for the ban on nuclear weapons testing, particularly atmospheric testing. It has been estimated that by 2020 between 200,000 to 460,000 people had died as a result of nuclear weapons testing, while the total number of deaths may rise up to 2.4 million people.<ref name="s257">{{cite web | last=Adams | first=Lilly | title=Resuming Nuclear Testing a Slap in the Face to Survivors | website=The Equation | date=May 26, 2020 | url=https://blog.ucsusa.org/lilly-adams/resuming-nuclear-testing-a-slap-in-the-face-to-survivors/ | access-date=July 16, 2024}}</ref>

==Criticism==
{{POV-section|date=January 2025}}
Nuclear arms tests have been criticized for its [[arms race]]<ref name="l904">{{cite web | last=Kinsella | first=William | title=The nuclear arms race's legacy: Contamination, staggering cleanup costs and a culture of secrecy • Missouri Independent | website=Missouri Independent | date=2023-08-04 | url=https://missouriindependent.com/2023/08/04/the-nuclear-arms-races-legacy-contamination-staggering-cleanup-costs-and-a-culture-of-secrecy/ | access-date=2025-01-07}}</ref> and its fallout,<ref name="c705">{{cite journal | last=Prăvălie | first=Remus | title=Nuclear Weapons Tests and Environmental Consequences: A Global Perspective | journal=Ambio | publisher=Springer Science and Business Media LLC | volume=43 | issue=6 | date=2014-02-22 | issn=0044-7447 | doi=10.1007/s13280-014-0491-1 | doi-access=free | pages=729–744 | pmid=24563393 | pmc=4165831 | bibcode=2014Ambio..43..729P }}</ref><ref name="s018">{{cite web | last=Seale | first=Jack | title=Britain's Nuclear Bomb Scandal: Our Story review – how the UK's atomic testing programme devastated lives | website=the Guardian | date=2024-11-20 | url=https://www.theguardian.com/tv-and-radio/2024/nov/20/britain-nuclear-bomb-scandal-our-story-review | access-date=2025-01-07}}</ref><ref name="u678">{{cite web | title=Banning nuclear explosions protects the environment | website=CTBTO | url=https://www.ctbto.org/news-and-events/news/banning-nuclear-explosions-protects-environment | access-date=2025-01-07}}</ref> with a potentially global fallout.

Nuclear weapons tests have been criticized by [[anti-nuclear movement|anti-nuclear activists]] as nuclear imperialism, colonialism,<ref name="u485">{{cite journal | last1=Hennaoui | first1=Leila | last2=Nurzhan | first2=Marzhan | title=Dealing with a Nuclear Past: Revisiting the Cases of Algeria and Kazakhstan through a Decolonial Lens | journal=The International Spectator | volume=58 | issue=4 | date=2023-10-02 | issn=0393-2729 | doi=10.1080/03932729.2023.2234817 | doi-access=free | pages=91–109 }}</ref> [[ecocide]], [[environmental racism]] and [[nuclear genocide]].<ref name="j999">{{cite web | last=Skinner | first=Rob | title='Against Nuclear Imperialism': peace, race and anti-colonialism in the early 1960s | website=University of Bristol | date=2021-09-30 | url=https://www.bristol.ac.uk/history/public-engagement/blackhistory/snapshots2021/nuclear/ | access-date=2025-01-03}}</ref><ref name="b190">{{cite web | last=Hsu | first=Hsuan L. | title=Nuclear colonialism | website=Environment & Society Portal | date=2014-05-21 | url=https://www.environmentandsociety.org/exhibitions/risk-and-militarization/nuclear-colonialism | access-date=2025-01-03}}</ref><ref name="w082">{{cite journal | last=Maguire | first=Richard | title=From the Guest Editor: The nuclear weapon and genocide: The beginning of a discussion | journal=Journal of Genocide Research | volume=9 | issue=3 | date=2007 | issn=1462-3528 | doi=10.1080/14623520701528866 | doi-access=free | pages=353–360 }}</ref>

The movement gained particularly in the 1960s and in the 1980s again.

The international day "End Nuclear Tests Day" raises critical awareness annually.<ref name="t465">{{cite web | last=Nations | first=United | title=End Nuclear Tests Day | publisher=United Nations | date=1945-07-16 | url=https://www.un.org/en/observances/end-nuclear-tests-day/history | access-date=2025-01-08}}</ref>

==Treaties against testing==
There are many existing anti-nuclear explosion treaties, notably the [[Partial Nuclear Test Ban Treaty]] and the [[Comprehensive Nuclear-Test-Ban Treaty|Comprehensive Nuclear Test Ban Treaty]]. These treaties were proposed in response to growing international concerns about environmental damage, among other risks. Nuclear testing involving humans also contributed to the formation of these treaties. Examples can be seen in the following articles:

* [[Desert Rock exercises]]
* [[Totskoye range nuclear tests]]

The Partial Nuclear Test Ban treaty makes it illegal to detonate a nuclear explosion anywhere except underground, in order to reduce atmospheric fallout. Most countries have signed and ratified the Partial Nuclear Test Ban, which came into effect in October 1963. Of the nuclear states, France, China, and North Korea have never signed the Partial Nuclear Test Ban Treaty.<ref>U.S. Department of State, [https://2009-2017.state.gov/t/isn/4797.htm Limited Test Ban Treaty].</ref>

The 1996 Comprehensive Nuclear-Test-Ban Treaty (CTBT) bans all nuclear explosions everywhere, including underground. For that purpose, the [[Comprehensive Nuclear-Test-Ban Treaty Organization Preparatory Commission|Preparatory Commission of the Comprehensive Nuclear-Test-Ban Treaty Organization]] is building an international monitoring system with 337 facilities located over the globe. 85% of these facilities are already operational.<ref>{{cite web|url= http://www.ctbto.org/fileadmin/user_upload/public_information/CTBT_Ending_Nuclear_Explosions_web.pdf|title=CTBTO Factsheet: Ending Nuclear Explosions |website=Ctbto.org |access-date=2012-05-23}}</ref> {{As of|2012|5}}, the CTBT has been signed by 183 States, of which 157 have also ratified. For the Treaty to enter into force it needs to be ratified by 44 specific nuclear technology-holder countries. These "Annex 2 States" participated in the negotiations on the CTBT between 1994 and 1996 and possessed nuclear power or research reactors at that time. The ratification of eight Annex 2 states is still missing: China, Egypt, Iran, Israel and the United States have signed but not ratified the Treaty; India, North Korea and Pakistan have not signed it.<ref>{{cite web|url= http://www.ctbto.org/the-treaty/status-of-signature-and-ratification/ |title=Status of signature and ratification |website=Ctbto.org |access-date=2012-05-23}}</ref>

The following is a list of the treaties applicable to nuclear testing:

{| class="wikitable sortable"
|-
! Name
! Agreement date
! In force date
! In effect today?
! Notes
|-

! Unilateral USSR ban
| {{dts|1958-03-31}}
| {{dts|1958-03-31}}
| no
| USSR unilaterally stops testing provided the West does as well.
|-

! Bilateral testing ban
| {{dts|1958-08-02}}
| {{dts|1958-10-31}}
| no
| USA agrees; ban begins on 31 October 1958, 3 November 1958 for the Soviets, and lasts until abrogated by a USSR test on 1 September 1961.
|-

! [[Antarctic Treaty|Antarctic Treaty System]]
| {{dts|1959-12-01}}
| {{dts|1961-06-23}}
| yes
| Bans testing of all kinds in Antarctica.
|-

! [[Partial Nuclear Test Ban Treaty]] (PTBT)
| {{dts|1963-08-05}}
| {{dts|1963-10-10}}
| yes
| Ban on all but underground testing.
|-

! [[Outer Space Treaty]]
| {{dts|1967-01-27}}
| {{dts|1967-10-10}}
| yes
| Bans testing on the moon and other celestial bodies.
|-

! [[Treaty of Tlatelolco]]
| {{dts|1967-02-14}}
| {{dts|1968-04-22}}
| yes
| Bans testing in South America and the Caribbean Sea Islands.
|-

! [[Nuclear Non-proliferation Treaty]]
| {{dts|1968-01-01}}
| {{dts|1970-03-05}}
| yes
| Bans the proliferation of nuclear technology to non-nuclear nations.
|-

! [[Seabed Arms Control Treaty]]
| {{dts|1971-02-11}}
| {{dts|1972-05-18}}
| yes
| Bans emplacement of nuclear weapons on the ocean floor outside territorial waters.
|-

! [[Strategic Arms Limitation Talks|Strategic Arms Limitation Treaty]] (SALT I)
| {{dts|1972-01-01}}
| 
| no
| A five-year ban on installing launchers.
|-

! [[Anti-Ballistic Missile Treaty]]
| {{dts|1972-05-26}}
| {{dts|1972-08-03}}
| no
| Restricts ABM development; additional protocol added in 1974; abrogated by the US in 2002.
|-

! [[Agreement on the Prevention of Nuclear War]]
| {{dts|1973-06-22}}
| {{dts|1973-06-22}}
| yes
| Promises to make all efforts to promote security and peace.
|-

! [[Threshold Test Ban Treaty]]
| {{dts|1974-07-01}}
| {{dts|1990-12-11}}
| yes
| Prohibits higher than 150 kt for underground testing.
|-

! [[Peaceful Nuclear Explosions Treaty]] (PNET)
| {{dts|1976-01-01}}
| {{dts|1990-12-11}}
| yes
| Prohibits higher than 150 kt, or 1500kt in aggregate, testing for peaceful purposes.
|-

! [[Moon Treaty]]
| {{dts|1979-01-01}}
| {{dts|1984-01-01}}
| no
| Bans use and emplacement of nuclear weapons on the moon and other celestial bodies.
|-

! [[Strategic Arms Limitation Talks|Strategic Arms Limitations Treaty]] (SALT II)
| {{dts|1979-06-18}}
| 
| no
| Limits strategic arms.  Kept but not ratified by the US, abrogated in 1986.
|-

! [[Treaty of Rarotonga]]
| {{dts|1985-08-06}}
| 
| ?
| Bans nuclear weapons in South Pacific Ocean and islands.  US never ratified.
|-

! [[Intermediate Range Nuclear Forces Treaty]] (INF)
| {{dts|1987-12-08}}
| {{dts|1988-06-01}}
| no
| Eliminated Intermediate Range Ballistic Missiles (IRBMs). Implemented by 1 June 1991. Both sides alleged the other was in violation of the treaty. Expired following US withdrawal, 2 August 2019.
|-

! [[Treaty on Conventional Armed Forces in Europe]]
| {{dts|1990-11-19}}
| {{dts|1992-07-17}}
| yes
| Bans categories of weapons, including conventional, from Europe. Russia notified signatories of intent to suspend, 14 July 2007.
|-

! [[START I|Strategic Arms Reduction Treaty I (START I)]]
| {{dts|1991-07-31}}
| {{dts|1994-12-05}}
| no
| 35-40% reduction in ICBMs with verification. Treaty expired 5 December 2009, renewed (see below).
|-

! [[Treaty on Open Skies]]
| {{dts|1992-03-24}}
| {{dts|2002-01-01}}
| yes
| Allows for unencumbered surveillance over all signatories.
|-

! [[US unilateral testing moratorium]]
| {{dts|1992-10-02}}
| {{dts|1992-10-02}}
| no
| George. H. W. Bush declares unilateral ban on nuclear testing.<ref name=armscontrol-ctbt>{{cite web |title=The Status of the Comprehensive Test Ban Treaty: Signatories and Ratifiers |url=https://www.armscontrol.org/factsheets/ctbtsig |date=March 2014 |publisher=Arms Control Association |access-date=June 29, 2014}}</ref> Extended several times, not yet abrogated.
|-

! [[START II|Strategic Arms Reduction Treaty (START II)]]
| {{dts|1993-01-03}}
| {{dts|2002-01-01}}
| no
| Deep reductions in ICBMs. Abrogated by Russia in 2002 in retaliation of US abrogation of ABM Treaty.
|-

! [[Southeast Asian Nuclear-Weapon-Free Zone Treaty]] (Treaty of Bangkok)
| {{dts|1995-12-15}}
| {{dts|1997-03-28}}
| yes
| Bans nuclear weapons from southeast Asia.
|-

! [[African Nuclear Weapon Free Zone Treaty]] (Pelindaba Treaty)
| {{dts|1996-01-01}}
| {{dts|2009-07-16}}
| yes
| Bans nuclear weapons in Africa.
|-

! [[Comprehensive Nuclear Test Ban Treaty]] (CTBT)
| {{dts|1996-09-10}}
|
| yes  (effectively)
| Bans all nuclear testing, peaceful and otherwise.  Strong detection and verification mechanism ([[CTBTO]]). US has signed and adheres to the treaty, though has not ratified it.
|-

! [[Treaty on Strategic Offensive Reductions]] (SORT, Treaty of Moscow)
| {{dts|2002-05-24}}
| {{dts|2003-06-01}}
| no
| Reduces warheads to 1700–2200 in ten years. Expired, replaced by START II.
|-

! [[START I]] treaty renewal
| {{dts|2010-04-08}}
| {{dts|2011-01-26}}
| yes
| Same provisions as START I.
|}

==Compensation for victims==
{{see also|Environmental impact of war}}

Over 500 atmospheric nuclear weapons tests were conducted at various sites around the world from 1945 to 1980. As public awareness and concern mounted over possible health hazards associated with exposure to [[nuclear fallout]], various studies were done to assess the extent of the hazard. A [[Centers for Disease Control and Prevention]]/ [[National Cancer Institute]] study claimed that nuclear fallout might have led to approximately 11,000 excess deaths, most caused by [[thyroid cancer]] linked to exposure to [[iodine-131]].<ref>{{cite book|url=http://books.nap.edu/catalog.php?record_id=10621|title=Exposure of the American Population to Radioactive Fallout from Nuclear Weapons Tests: A Review of the CDC-NCI Draft Report on a Feasibility Study of the Health Consequences to the American Population from Nuclear Weapons Tests Conducted by the United States and Other Nations|first=National Research|last=Council|date=11 February 2003|doi=10.17226/10621|pmid=25057651|isbn=9780309087131}}</ref>

* '''United States''': Prior to March 2009, the US was the only nation to compensate nuclear test victims. Since the [[Radiation Exposure Compensation Act]] of 1990, more than $1.38&nbsp;billion in compensation has been approved. The money is going to people who took part in the tests, notably at the [[Nevada Test Site]], and to others exposed to the radiation from these tests.<ref>{{cite web|url=http://www.usdoj.gov/civil/omp/omi/Tre_SysClaimsToDateSum.pdf|title=Radiation Exposure Compensation System: Claims to Date Summary of Claims Received by 06/11/2009|website=Usdoj.gov}}</ref> As of 2017, the US government has refused to pay for the medical care of troops who associate their health problems with the construction of [[Runit Dome]] in the Marshall Islands.<ref>{{cite web|title=Troops Who Cleaned Up Radioactive Islands Can't Get Medical Care |url=https://www.nytimes.com/2017/01/28/us/troops-radioactive-islands-medical-care.html |website=[[The New York Times]] |date=28 January 2017 }}</ref>
* '''France''': In March 2009, the French Government offered to compensate victims for the first time, and legislation was drafted which would allow payments to people who suffered health problems related to the tests.<ref>{{cite news |last1=Hardach |first1=Sophie |last2=Shirbon |first2=Estelle |date=24 March 2009 |title=France to compensate victims of nuclear testing |url=https://www.reuters.com/article/us-france-nuclear/france-to-compensate-victims-of-nuclear-testing-idUKTRE52N4W720090324/ |work=[[Reuters]] |access-date=28 January 2025}}</ref> The payouts would be available to victims' descendants and would include Algerians, who were exposed to nuclear testing in the Sahara in 1960. Victims say the eligibility requirements for compensation are too narrow.{{Citation needed|date=October 2022}}
* '''United Kingdom''': There is no formal British government compensation program. Nearly 1,000 veterans of [[Christmas Island (Kiritimati)#Nuclear bomb tests|Christmas Island nuclear tests]] in the 1950s are engaged in legal action against the Ministry of Defense for negligence. They say they suffered health problems and were not warned of potential dangers before the experiments.{{Citation needed|date=October 2022}}
* '''Russia''': Decades later, Russia offered compensation to veterans who were part of the [[Totskoye nuclear exercise|1954 Totsk test]]. There was no compensation to civilians made sick by the Totsk test. Anti-nuclear groups say there has been no government compensation for other nuclear tests.{{Citation needed|date=October 2022}}
* '''China''': China has undertaken highly secretive atomic tests in remote deserts in a Central Asian border province. Anti-nuclear activists say there is no known government program for compensating victims.{{Citation needed|date=October 2022}}

==Milestone nuclear explosions==
The following list is of milestone nuclear explosions. In addition to the [[atomic bombings of Hiroshima and Nagasaki]], the first nuclear test of a given weapon type for a country is included, as well as tests that were otherwise notable (such as the largest test ever). All yields (explosive power) are given in their estimated energy equivalents in kilotons of [[trinitrotoluene|TNT]] (see [[TNT equivalent]]). [[List of nuclear tests#Alleged tests|Putative tests]] (like [[Vela incident]]) have not been included.

{|class="wikitable sortable"
|- style="background-color:#efefef;"
! Date
! Name
! data-sort-type="number" | {{longitem|[[nuclear weapon yield|Yield]] (kt)}}
! Country
!class="unsortable"| Significance
|-
| {{Birth date|1945|07|16}}
| '''''[[Trinity test|Trinity]]'''''
| {{sort|19|18–20}}
| [[Nuclear weapons and the United States|United States]]
| First fission-device test, first plutonium implosion detonation.
|-
| {{Birth date|1945|08|06}}
| '''''[[Little Boy]]'''''
| {{sort|15|12–18}}
| [[Nuclear weapons and the United States|United States]]
| [[Atomic bombings of Hiroshima and Nagasaki|Bombing]] of [[Hiroshima]], [[Japan]], first detonation of a uranium gun-type device, first use of a nuclear device in combat.
|-
| {{Birth date|1945|08|09}}
| '''''[[Fat Man]]'''''
| {{sort|20.5|18–23}}
| [[Nuclear weapons and the United States|United States]]
| [[Atomic bombings of Hiroshima and Nagasaki|Bombing]] of [[Nagasaki, Nagasaki|Nagasaki]], [[Japan]], second detonation of a plutonium implosion device (the first being the Trinity Test), second and last use of a nuclear device in combat.
|-
| {{Birth date|1949|08|29}}
| '''''[[RDS-1]]'''''
| 22
| [[Soviet atomic bomb project|Soviet Union]]
| First fission-weapon test by the Soviet Union.
|-
| {{Birth date|1951|05|08}}
| '''''[[Operation Greenhouse|George]]'''''
| 225
| [[Nuclear weapons and the United States|United States]]
| First boosted nuclear weapon test, first weapon test to employ fusion in any measure.
|-
| {{Birth date|1952|10|03}}
| '''''[[Operation Hurricane|Hurricane]]'''''
| 25
| {{nowrap|[[Nuclear weapons and the United Kingdom|United Kingdom]]}}
| First fission weapon test by the United Kingdom.
|-
| {{Birth date|1952|11|01}}
| '''''[[Ivy Mike]]'''''
| 10,400
| [[Nuclear weapons and the United States|United States]]
| First "[[Nuclear_weapon_design#Two-stage_thermonuclear_weapons|staged]]" thermonuclear weapon, with cryogenic fusion fuel, primarily a test device and not weaponized.
|-
| {{nowrap|{{Birth date|1952|11|16}}}}
| '''''[[Ivy King]]'''''
| 500
| [[Nuclear weapons and the United States|United States]]
| Largest pure-fission weapon ever tested.
|-
| {{Birth date|1953|08|12}}
| '''''[[RDS-6s]]'''''
| 400
| [[Soviet atomic bomb project|Soviet Union]]
| First fusion-weapon test by the Soviet Union (not "staged").
|-
| {{Birth date|1954|03|01}}
| '''''[[Castle Bravo]]'''''
| 15,000
| [[Nuclear weapons and the United States|United States]]
| First "staged" thermonuclear weapon using dry fusion fuel. A serious [[nuclear fallout]] accident occurred. Largest nuclear detonation conducted by United States.
|-
| {{Birth date|1955|11|22}}
| '''''[[RDS-37]]'''''
| 1,600
| [[Soviet atomic bomb project|Soviet Union]]
| First "staged" thermonuclear weapon test by the Soviet Union (deployable).
|-
| {{Birth date|1957|05|31}}
| '''''[[Orange Herald]]'''''
| 720
| [[Nuclear weapons and the United Kingdom|United Kingdom]]
| Largest boosted fission weapon ever tested. Intended as a fallback "in megaton range" in case British thermonuclear development failed.
|-
| {{Birth date|1957|11|08}}
| '''''[[Operation Grapple#Grapple X|Grapple X]]'''''
| 1,800
| [[Nuclear weapons and the United Kingdom|United Kingdom]]
| First (successful) "staged" thermonuclear weapon test by the United Kingdom
|-
| {{Birth date|1960|02|13}}
| {{nowrap|'''''[[Gerboise Bleue]]'''''}}
| 70
| [[France and weapons of mass destruction|France]]
| First fission weapon test by France.
|-
| {{Birth date|1961|10|31}}
| '''''[[Tsar Bomba]]'''''
| 50,000
| [[Soviet atomic bomb project|Soviet Union]]
| Largest thermonuclear weapon ever tested—scaled down from its initial 100&nbsp;Mt design by 50%.
|-
| {{Birth date|1964|10|16}}
| '''''[[596 (nuclear test)|596]]'''''
| 22
| [[People's Republic of China and weapons of mass destruction|China]]
| First fission-weapon test by the People's Republic of China.
|-
| {{Birth date|1967|06|17}}
| '''''[[Chinese nuclear test No. 6|Test No. 6]]'''''
| 3,300
| [[People's Republic of China and weapons of mass destruction|China]]
| First "staged" thermonuclear weapon test by the People's Republic of China.
|-
| {{Birth date|1968|08|24}}
| '''''[[Canopus (nuclear test)|Canopus]]'''''
| 2,600
| [[France and weapons of mass destruction|France]]
| First "staged" thermonuclear weapon test by France
|-
| {{Birth date|1974|05|18}}
| {{nowrap|'''''[[Smiling Buddha]]'''''}}
| 12
| [[India and weapons of mass destruction|India]]
| First fission nuclear explosive test by India.
|-
| {{Birth date|1998|05|11}}
| '''''[[Pokhran-II]]'''''
| 45–50
| [[India and weapons of mass destruction|India]]
| First potential fusion-boosted weapon test by India; first deployable fission weapon test by India.
|-
| {{Birth date|1998|05|28}}
| '''''[[Chagai-I]]'''''
| 40
| [[Pakistan and weapons of mass destruction|Pakistan]]
| First fission weapon (boosted) test by Pakistan<ref name=pakfas>{{Cite web |title=Pakistan Nuclear Weapons: A Brief History of Pakistan's Nuclear Program |url=http://www.fas.org/nuke/guide/pakistan/nuke/ |publisher=[[Federation of American Scientists]] |date=11 December 2002 |access-date=30 October 2019}}</ref>
|-
| {{Birth date|2006|10|09}}
| '''''{{nowrap|[[2006 North Korean nuclear test|2006 nuclear test]]}}'''''
| {{sort|0.5|under 1}}
| {{nowrap|[[North Korea and weapons of mass destruction|North Korea]]}}
| First fission-weapon test by North Korea (plutonium-based).
|-
| {{Birth date|2017|09|03}}
| '''''{{nowrap|[[2017 North Korean nuclear test|2017 nuclear test]]}}'''''
| {{sort|110|200–300}}
| {{nowrap|[[North Korea and weapons of mass destruction|North Korea]]}}
| First "staged" thermonuclear weapon test claimed by North Korea.
|}

;Note
* "Staged" refers to whether it was a "true" [[thermonuclear weapon]] of the so-called [[Teller–Ulam]] configuration or simply a form of a [[boosted fission weapon]]. For a more complete list of nuclear test series, see [[List of nuclear tests]]. Some exact yield estimates, such as that of the [[Tsar Bomba]] and the tests by India and Pakistan in 1998, are somewhat contested among specialists.

==See also==
{{Portal|Nuclear technology}}
{{Div col}}
* {{annotated link|Atmospheric focusing}}
* {{annotated link|Atomic Testing Museum}} (in Nevada in the US)
* {{annotated link|High-altitude nuclear explosion}}
* {{annotated link|Historical nuclear weapons stockpiles and nuclear tests by country}}
* {{annotated link|History of nuclear weapons}}
* {{annotated link|International Day against Nuclear Tests}}
* ''{{annotated link|How to Photograph an Atomic Bomb}}''
* {{annotated link|List of military nuclear accidents}} (including nuclear weapons accidents)
* {{annotated link|List of nuclear weapons tests of the United States}}
* {{annotated link|List of states with nuclear weapons}}
* {{annotated link|Live fire exercise}}
* {{annotated link|National Technical Means}}
* [[:Category:Nuclear test sites|Nuclear test sites]]
* {{annotated link|Nuclear ethics}}
* {{annotated link|Nuclear weapons design}}
* {{annotated link|Project Gnome}}
* {{annotated link|Rope trick effect}}
* {{annotated link|Subsidence crater}}
* {{annotated link|Test Readiness Program}}
* ''{{annotated link|Trinity and Beyond}}'' (documentary about nuclear weapon testing)
{{Div col end}}

== Explanatory notes ==
{{Notelist}}

==Citations==
{{Reflist}}

== General and cited references ==
{{Refbegin}}
* Gusterson, Hugh. ''Nuclear Rites: A Weapons Laboratory at the End of the Cold War''. Berkeley, CA: University of California Press, 1996.
* Hacker, Barton C. ''Elements of Controversy: The Atomic Energy Commission and Radiation Safety in Nuclear Weapons Testing, 1947–1974''. Berkeley, CA: University of California Press, 1994.
* Rice, James. Downwind of the Atomic State: Atmospheric Testing and the Rise of the Risk Society. (New York University Press, 2023). https://nyupress.org/9781479815340/downwind-of-the-atomic-state/ 
* Schwartz, Stephen I. ''Atomic Audit: The Costs and Consequences of U.S. Nuclear Weapons''. Washington, D.C.: Brookings Institution Press, 1998.
* Weart, Spencer R. ''Nuclear Fear: A History of Images''. Cambridge, MA: Harvard University Press, 1985.
{{Refend}}

==External links==
{{Commons category|Nuclear weapon tests}}
* [https://fas.org/nuke/intro/nuke/index.html Federation of American Scientists] {{Webarchive|url=https://web.archive.org/web/20160904031515/http://fas.org/nuke/intro/nuke/index.html |date=2016-09-04 }}
* [http://www.ctbto.org/ Preparatory Commission for the Comprehensive Nuclear-Test-Ban-Treaty Organization]
* [http://nuclearweaponarchive.org/index.html Nuclear Weapon Archive]
* [http://www.nuclearfiles.org/menu/key-issues/nuclear-weapons/issues/testing/ NuclearFiles.org]
* [http://www.bikiniatoll.com/whatrad.html What About Radiation on Bikini Atoll?]
* {{YouTube|WAnqRQg-W0k|"Time-lapse map of all nuclear weapon tests from 1945 to 1998."}}
* [http://thebulletin.org/ Bulletin of the Atomic Scientists]
* [https://web.archive.org/web/20110905235003/http://alsos.wlu.edu/default.aspx Alsos Digital Library for Nuclear Issues]
* [http://www.atomcentral.com Atomic Bomb website and nuclear weapon testing articles]
* [https://www.wilsoncenter.org/nuclear-history-documents The Woodrow Wilson Center's Nuclear Proliferation International History Project]

{{US Nuclear Tests}}
{{Authority control}}

{{DEFAULTSORT:Nuclear Weapons Testing}}
[[Category:Nuclear weapons testing| ]]
[[Category:Nuclear weapons|Testing]]