View source for Canopus (nuclear test)

{{Short description|France's largest nuclear test}}
{{italic title}}
{{Infobox nuclear weapons test
| name = ''Canopus''
| image = French nuclear test Canopus.jpg <!-- Image is under fair use -->
| image_size = 
| map_type            = French Polynesia
| map_alt             = 
| map_caption         = Location of the test site
| map_size            = 
| map_dot_label       = 
| map_dot_mark        = 
| relief              = 
| alt = 
| caption = ''Canopus'' [[mushroom cloud]]
| country = [[France]]
| test_series = [[1966–70 French nuclear tests|1966–70 series]]
| test_site = [[Fangataufa]], [[French Polynesia]]
| coordinates = {{coord|22|13|40|S|138|38|38|W|display=inline}}
| date = {{Start date and age|1968|08|24|df=y}} 
| test_type = [[Nuclear weapons testing#Types|Atmospheric]]
| test_altitude = 520 m
| device_type = Thermonuclear
| yield = 2.6 [[TNT equivalent|Mt]] (10878.4 TJ)
| summary = 
| previous_test = ''[[Pollux (nuclear test)|Pollux]]''
| next_test = ''[[Procyon (nuclear test)|Procyon]]''
}}

'''''Canopus''''' (or ''Opération Canopus'') was the [[codename]] of the first [[Nuclear weapons and France|French]] [[Thermonuclear weapons|two-stage thermonuclear]] test. It was conducted by the Pacific Carrier Battle Group (nicknamed ''Alfa Force'') on 24 August 1968, at the Pacific Experiments Centre near [[Fangataufa]] [[atoll]], [[French Polynesia]].<ref>{{cite web|url=http://www.assemblee-nationale.fr/11/pdf/rap-oecst/I3571.pdf|title=Rapport sur les incidences environnementales et sanitaires des essais nucleaires effectues par la France entre 1960 et 1996 et elements de comparaison avec les essais des autres puissances nucleaires|last=National Assembly of the French Republic|date=5 February 2001|website=assemblee-nationale.fr|language=French|accessdate=8 August 2020}}</ref> The test made France the fifth country to test a thermonuclear device after the [[United States]], the [[Soviet Union]], the [[United Kingdom]] and [[China]]. It was the most powerful nuclear device ever detonated by France.<ref>{{Cite journal |last=Norris |first=Robert S. |date=1996 |title=French and Chinese Nuclear Weapon Testing |url=https://www.jstor.org/stable/44471493 |journal=Security Dialogue |volume=27 |issue=1 |pages=39–54 |issn=0967-0106}}</ref>

== History ==
In 1966, France was able to use [[nuclear fusion|fusion]] fuel to [[boosted fission weapon|boost]] [[plutonium]] implosion devices with the [[Rigel (nuclear test)|Rigel]] shot. [[Robert Dautray]] (real name Ignatz Koushelewitz), a nuclear [[physicist]], was selected by the [[Commissariat à l'Energie Atomique|CEA]] to lead the development effort to construct a two-stage weapon. France did not have the ability to produce the materials needed for a two-stage thermonuclear device at the time, so 151 tons of [[heavy water]] was purchased from Norway and an additional 168 tons from the United States. This heavy water went into [[nuclear reactors]] in 1967 to produce [[tritium]] needed for the device.{{Citation needed|date=March 2010}}

France was to test the new device as part of a 5-shot series conducted at the [[nuclear testing]] grounds in [[French Polynesia]]. The device weighed three tons and used a [[lithium deuteride]] [[Teller-Ulam design|secondary stage]] with a highly [[enriched uranium]] jacket primary.

Fangataufa was selected as the location of the shot due to its isolation in respect to the main base on [[Mururoa]]. The device was suspended from a large [[hydrogen]] filled [[balloon]]. It was detonated at 18:30:00.5 [[GMT]] with a 2.6 [[TNT equivalent|megaton]] yield at an altitude of {{convert|1800|ft|disp=flip}}. Nominal yield was {{convert|2.6|MtTNT|lk=in}} .<ref>{{cite web |title=24 August 1968 - Fremch 'Canopus' test |url=http://www.ctbto.org/specials/infamous-anniversaries/24-august-1968-french-canopus-test/ |publisher=CTBTO |archive-url=https://web.archive.org/web/20111008200617/http://www.ctbto.org/specials/infamous-anniversaries/24-august-1968-french-canopus-test/ |archive-date=8 October 2011}}</ref>  As a result of the successful detonation, France became the 5th [[nuclear nations|thermonuclear nation]].

A flotilla codenamed Alfa Force led by French aircraft carrier ''[[French aircraft carrier Clemenceau (R98)|Clemenceau]]'' deployed to the south Pacific during the time of the test. The naval force present around the two atolls massed more than 120,000 tons displacement and represented more than 40% of the tonnage of the entire French navy.<ref>{{cite web |url=http://www.netmarine.net/g/dossiers/mururoa/index.htm |title=La Marine à Mururoa |first=Jean-Michel |last=Roche |work=netmarine.net |accessdate=24 October 2014|language=fr}}</ref>

== International reactions ==

The announcement by France in the late 1960s to test a hydrogen bomb provoked the [[People's Republic of China]] to conduct a full scale hydrogen bomb test of its own on 17 June 1967.<ref>{{cite web|url=http://www.atomicforum.org/france/1968.html|title=Atomic Forum; French Atmospheric Nuclear Testing Series - 1968|archive-url=https://web.archive.org/web/20070520061654/http://www.atomicforum.org/france/1968.html|archive-date=20 May 2007}}</ref>

== See also ==
* ''[[Gerboise Bleue]]'' (French first atmospheric A-bomb)
* ''[[Agate (nuclear test)|Agate]]'' (French first underground A-bomb)
* ''[[Force de frappe]]''
* [[Nuclear weapons and France]]
* [[List of states with nuclear weapons]]
* [[History of nuclear weapons]]

==External links==
*[http://atomicforum.org/france/france.html France's Nuclear Weapons Program] at the [https://web.archive.org/web/20081117094333/http://www.atomicforum.org/ Atomic Forum]
* {{in lang|fr}} [https://web.archive.org/web/20081121020036/http://www.point-zero-penelope.org/ Archives sur le Centre d'Expérimentations Nucléaires du Pacifique (C.E.P.) à Moruroa, Hao et Fangataufa]

== References ==
{{reflist}}

{{Nuclear weapons tests of France}}

[[Category:French nuclear weapons testing]]
[[Category:1968 in France]]
[[Category:1960s in French Polynesia]]
[[Category:1968 in the French colonial empire]]
[[Category:August 1968 in Oceania]]
[[Category:Environmental racism]]