Previous Next

Grappling with the Bomb

Timeline and glossary

Nuclear timeline, 1945–1963

16 July 1945

Alamogordo, New Mexico, USA

United States conducts first-ever nuclear test, codenamed ‘Trinity.’

6 August 1945

Hiroshima, Japan

US aircraft Enola Gay drops the atomic weapon ‘Little Boy’ on Hiroshima, killing 80,000 people immediately and an estimated 100,000 people within six months.

9 August 1945

Nagasaki, Japan

US aircraft Bockscar drops the atomic weapon ‘Fat Man’ on Nagasaki, killing 70,000 people immediately and tens of thousands in following months.

30 June 1946

Bikini Atoll, Marshall Islands

Under Operation Crossroads, United States conducts the first of two atomic tests at Bikini Atoll in the Marshall Islands. ‘Able’ and ‘Baker’ are the first of 67 atmospheric tests in the Marshall Islands between 1946–1958.

6 August 1948

Hiroshima, Japan

Hiroshima’s first Peace Festival.

29 August 1949

Semipalatinsk, Kazakhstan

USSR conducts first atomic test RDS-1 in Operation Pervaya molniya (Fast lightning), dubbed ‘Joe-1’ by United States.


Korean peninsula

United States, Britain and Australia, under a United Nations mandate, join military operations in Korea following clashes between forces from the south and north of Korea. The Democratic People’s Republic is backed by the newly created People’s Republic of China.

3 October 1952

Monte Bello Islands, Western Australia

Under Operation Hurricane, United Kingdom begins its nuclear testing program in Australia with a 25 kiloton atomic test.

1 November 1952

Bikini Atoll, Marshall Islands

United States conducts its first hydrogen bomb test, codenamed ‘Mike’ (10.4 megatons) as part of Operation Ivy.

12 August 1953

Semipalatinsk, Kazakhstan

USSR tests first hydrogen bomb RDS-6 (‘Joe-4’).

15–27 October 1953

Emu Field, South Australia

Under Operation Totem, United Kingdom conducts two atomic tests (‘Totem One’ with an 8 kiloton yield and ‘Totem Two’ with 10 kilotons) in the South Australian desert.

1 March 1954

Bikini Atoll, Marshall Islands

United States conducts hydrogen bomb test at Bikini Atoll, codenamed ‘Bravo’. The test showers radioactive fallout over the country, especially northern atolls and Japanese fishing vessel Lucky Dragon (six H-bomb tests under Operation Castle between February and May).

6–8 August 1955

Hiroshima, Japan

First World Conference against Atomic and Hydrogen Bombs held on anniversary of atomic attacks.

16 May and 19 June 1956

Monte Bello Islands, Western Australia

United Kingdom conducts two atomic tests (‘Mosaic One’—15 kilotons and ‘Mosaic Two’—60 kilotons) off coast of Western Australia under Operation Mosaic.

June 1956

Christmas Island (Kiritimati), British Gilbert and Ellice Islands Colony

United Kingdom begins construction of airstrip, military encampment and scientific bunkers to prepare for Operation Grapple hydrogen bomb tests.

27 September–22 October 1956

Maralinga, South Australia

United Kingdom conducts four atomic tests (‘One Tree’, ‘Marcoo’, ‘Kite’, ‘Breakaway’) in South Australian desert under Operation Buffalo.

October–December 1956

Egypt and Hungary

Cold War political tensions rise following United Kingdom, French and Israeli attack on Egypt during Suez crisis, and crushing of Hungarian uprising by Soviet troops.

9 January 1957

London, England

United Kingdom Prime Minister Sir Anthony Eden resigns over Suez crisis; replaced the next day by Harold Macmillan, who restructures UK strategic, colonial and nuclear policy.

15 May 1957

Malden Island, British Gilbert and Ellice Islands Colony

Under Operation Grapple, United Kingdom conducts Grapple 1 ‘Short Granite’ atomic test (0.3 megaton).

31 May 1957

Malden Island, British Gilbert and Ellice Islands Colony

United Kingdom conducts Grapple 2 ‘Orange Herald’ atomic test (0.72 megaton).

19 June 1957

Malden Island, British Gilbert and Ellice Islands Colony

United Kingdom conducts Grapple 3 ‘Purple Granite’ atomic test (0.2 megaton).

July 1957

London, England

After failure to reach megaton range at Malden Island tests, UK Cabinet agrees to proceed with further hydrogen bomb tests, but relocated to Christmas Island. Further atomic trigger tests to continue in Australia to support H-bomb program.

14 September–9 October 1957

Maralinga, South Australia

Under Operation Antler, United Kingdom conducts three atomic tests (‘Tadje’, ‘Biak’ and ‘Taranaki’) between 0.9 and 26.6 kilotons in South Australian desert.

4 October 1957

Tyuratam missile range, Kazakhstan

USSR launches Sputnik 1, the first artificial satellite to orbit the earth, highlighting Soviet technological advances and exacerbating Cold War fears in the West.

10 October 1957

Cumberland, United Kingdom

Fire at the Windscale nuclear reactor releases radioactive contamination across the United Kingdom and Europe. Windscale is being used to produce tritium for the UK H-bomb program.

8 November 1957

Christmas Island (Kiritimati), British Gilbert and Ellice Islands Colony

United Kingdom restarts Operation Grapple on Christmas Island, with Grapple X hydrogen bomb test (1.8 megatons).

31 March 1958

Moscow, USSR

USSR suspends its nuclear test program, in lead up to negotiations for a nuclear test ban treaty.

28 April 1958

Christmas Island (Kiritimati), British Gilbert and Ellice Islands Colony

United Kingdom conducts Grapple Y hydrogen bomb test (2.8 megatons), with radioactive fallout over Christmas Island and naval task force.

28 April–18 August 1958

Enewetak Atoll, Marshall Islands and Johnston Atoll

United States begins Operation Hardtack, a series of 35 atomic and hydrogen bomb tests on Bikini and Enewetak atolls, with two high-altitude detonations (‘Teak’ and ‘Orange’) from rockets launched from Johnston Atoll.

22 August 1958

London, England

United States and Britain announce one-year moratorium of nuclear tests to commence on 31 October (United Kingdom conducts four more tests before deadline).

22 August 1958

Christmas Island (Kiritimati), British Gilbert and Ellice Islands Colony

United Kingdom conducts Grapple Z atomic test codenamed ‘Pennant’ (24 kilotons), with the bomb on a tethered balloon.

2 September 1958

Christmas Island (Kiritimati), British Gilbert and Ellice Islands Colony

United Kingdom conducts Grapple Z hydrogen bomb test codenamed ‘Flagpole’ (1 megaton).

11 September 1958

Christmas Island (Kiritimati), British Gilbert and Ellice Islands Colony

United Kingdom conducts Grapple Z hydrogen bomb test codenamed ‘Halliard’ (0.8 megaton).

23 September 1958

Christmas Island (Kiritimati), British Gilbert and Ellice Islands Colony

United Kingdom conducts Grapple Z atomic test codenamed ‘Burgee’ (25 kilotons), with the bomb on a tethered balloon.

October–December 1958

Geneva, Switzerland

United States, United Kingdom and USSR hold talks in Geneva to establish a moratorium for nuclear testing.

13 February 1960–25 April 1961

Reggane, (French) Algeria

France begins its nuclear weapons program with four atmospheric atomic tests in the Sahara desert, codename ‘Gerboise’.

7 May 1960

Nevada, USA

United States announces resumption of underground nuclear testing.

30 August 1961

Moscow, USSR

USSR announces it will end a three-year moratorium on atmospheric nuclear testing, and tests restart the next day.

30 October 1961

Severny Island, Novaya Zemlya

USSR tests the most powerful thermonuclear weapon ever detonated, at 58 megatons. The world’s largest hydrogen bomb (RDS-220 code name ‘Vanya’ or ‘Tsar Bomba’) is the most powerful man-made explosion in human history.

7 November 1961

In Eker, (French) Algeria

France begins series of 13 underground atomic tests in the Hoggar Massif at In Eker in the Sahara desert, which continue after the Evian peace accords that end Algeria’s independence struggle.

January 1962

Washington DC, USA

United States announces resumption of nuclear testing in the Pacific, to begin on Christmas Island in April.

22 April–11 July 1962

Christmas Island (Kiritimati), British Gilbert and Ellice Islands Colony and Johnston Atoll

In Operation Dominic 1, United States conducts 24 atmospheric nuclear tests using United Kingdom infrastructure on Christmas Island, combined with one successful rocket launch from Johnston Atoll (the ‘Starfish Prime’ high-altitude nuclear test on 9 July under Operation Fishbowl).

2 October–3 November 1962

Johnston Atoll

United States conducts further nuclear tests in Operation Dominic. Nuclear warheads on rockets are fired from Johnston Island for high-altitude detonation (with several failed launches). Two submarine-launched missiles with nuclear warheads are test-fired. Five nuclear weapons are also dropped from aircraft for air bursts in the vicinity of Johnston Island.

14–28 October 1962


The Cuban Missile Crisis threatens global nuclear warfare, as John F. Kennedy and Nikita Khrushchev face off over nuclear missile deployments in Cuba and Turkey.

5 August 1963

Moscow, USSR

United States, Soviet Union and United Kingdom sign Partial Test Ban Treaty.

Over 50 years, the Western powers used the Pacific region as a laboratory for nuclear testing.

Between 1946 and 1958, the United States conducted 67 atomic and hydrogen bomb tests at Bikini and Enewetak atolls in the Marshall Islands. In 1962, there were 24 further US atmospheric nuclear tests at Christmas (Kiritimati) Island, as well as five atmospheric airbursts and nine high-altitude nuclear tests, with warheads launched on missiles from Johnston (Kalama) Atoll and submarines.

Britain tested nuclear weapons in Oceania between 1952 and 1958. There were 12 atomic tests at the Monte Bello Islands, Maralinga and Emu Field in Australia (1952–57). These were followed by nine hydrogen and atomic bomb tests in 1957–58 at Malden Island and Christmas (Kiritimati) Island in the British Gilbert and Ellice Islands Colony (GEIC)—today the Republic of Kiribati.

France conducted four atmospheric nuclear tests at Reggane and 13 underground tests at In Eker in the Sahara desert in Algeria between 1960 and 1966. France then moved its nuclear test sites to the South Pacific. From 1966 to 1996, France conducted 193 atmospheric and underground tests at Moruroa and Fangataufa atolls in French Polynesia.

Glossary of acronyms and abbreviations


Atomic bomb


Atomic Energy Commission


Air Force Office of Atomic Energy (US)


Municipal Archives of Girona


The Australian National University


Australian Radiation Protection and Nuclear Safety Agency


Atomic Weapons Research Establishment


British Broadcasting Corporation


British Nuclear Test Veterans Association


British Phosphate Commission




Central Intelligence Agency


Campaign for Nuclear Disarmament


Direct Action Committee Against Nuclear War


Distinguished Service Cross


Distinguished Service Order


Defense Threat Reduction Information Analysis Center


Efficiency Decoration


Foreign and Commonwealth Office


Fiji Royal Naval Volunteer Reserve


Fellow of the Royal Society


Knight Grand Cross, Order of St Michael and St George


Gilbert and Ellice Islands Colony


Hydrogen bomb


Her Majesty’s Australian Ship


Her Majesty’s Government


Her Majesty’s New Zealand Ship


Her Majesty’s Ship


International Court of Justice


International Commission on Radiological Protection


International Geophysical Year


Intelligence and Security Department, UK Colonial Office


Johnston Atoll Radiological Survey


Joint Task Force 7


Knight Commander of the Most Excellent Order of the British Empire


Knight Commander of the Royal Victorian Order


Knight of the Order of St John


multicolour flourescent in situ hybridsation


British domestic intelligence agency


British overseas intelligence agency (also known as SIS)


Marshall Islands Nuclear Documentation Database




Ministry of Defence


Member of Parliament


Meritorious Service Decoration (Fiji)




Motor Vessel


Navy, Army and Air Forces Institute


National Council for the Abolition of Nuclear Weapons Tests


Nuclear Community Charity Fund


Nuclear Claims Tribunal


Nuclear Free and Independent Pacific


National Library of Australia


National Radiological Protection Board


New Zealand


New Zealand Defence Force


New Zealand Nuclear Test Veterans Association


New Zealand Returned Services Association


Medal of the Order of Australia


Order of the British Empire


Order of Merit


Officer of the New Zealand Order of Merit


Pacific Manuscripts Bureau


Privy Council of the United Kingdom


Pacific Conference of Churches


Pacific Concerns Resource Centre


Peace Pledge Union


Quartz Fibre Electroscope


Queen’s Service Medal


Royal Australian Air Force


Royal Air Force


Royal Fiji Military Forces (pre-1987)/Republic of Fiji Military Forces (post-1987)


Republic of Marshall Islands


Royal Navy


Royal New Zealand Air Force


Royal New Zealand Navy


Royal Voluntary Service


Supreme Command for the Allied Powers


Safety and Ecology Corporation Ltd


Security Intelligence Service


South Pacific Air Lines


South Pacific Regional Environmental Program


Troop transport


Trust Territory of the Pacific Islands


United Kingdom


United Kingdom Atomic Energy Authority


United Nations


United Nations Educational, Scientific and Cultural Organization


United States


United States Defense Threat Reduction Agency


United States Ship


Union of Soviet Socialist Republics


Woomera Rocket Area


Women’s Voluntary Service

A note on terminology

As I read archival documents from the 1950s, I had the mental image of some poor British squaddie typing out long lists of Fijian soldiers deployed for Operation Grapple, and cursing when he got to Sapper Silivakadua Naikawakawakawavesi. There are quite a few mistakes in the files, from the days before electric typewriters and correcting fluid.

Beyond obvious errors, the archival documents cited in this book use a variety of spellings, such as Eniwitok instead of Enewetak for the nuclear test site in the Marshall Islands. There are also many examples where Europeans have used different names for atolls than those used by indigenous communities, such as Penrhyn/Tongareva, Fanning/Tabuaeran or Johnston/Kalama. For consistency throughout the book, I have retained the name ‘Christmas Island’, in spite of local usage. The current name in the i-Kiribati language of the Republic of Kiribati is ‘Kiritimati’, while Fijians spell Christmas as ‘Kirisimasi’.

This book will not go into detailed analysis of the different prototypes for British atomic and hydrogen bombs, nor provide complete data on the types of radiation generated during the Grapple nuclear detonations—the footnotes provide a number of sources for readers interested in greater technical detail.

However, for a general audience, here are a few brief definitions of terms used in the book:

Atomic weapons rely on nuclear fission, where the nucleus of uranium or plutonium splits into lighter elements, instantly releasing massive amounts of energy. A nuclear detonation differs from conventional explosives due to the generated heat, blast and especially radiation.

In contrast to atom bombs, thermonuclear or hydrogen weapons rely instead on nuclear fusion. Some early hydrogen bombs in the 1950s, using a mixture of tritium and deuterium, relied on atomic triggers to generate the massive heat and pressure required start the fusion process.

The explosive yield of a nuclear weapon is measured in kilotons (kt, equivalent to 1,000 tons of TNT explosive) or megatons (mt, 1,000,000 tons equivalent). The bomb that destroyed Hiroshima was only 12 kt, whereas larger thermonuclear or hydrogen bombs have an explosive power greater than 1 megaton.

Fallout is tiny particles of dirt, weapon debris, fission products or other substances contaminated with radioactivity. These particles are spread into the atmosphere following a nuclear explosion, then return to earth, especially through rainfall. Fallout can be blown for some distance by atmospheric or stratospheric winds.

Some nuclear detonations are fired from a tower or low-level balloon and are defined as a ground burst, generating extensive radioactive fallout. Other tests are air bursts, detonated at higher altitudes in an attempt to limit the amount of irradiated soil and debris.

Unstable atoms have either an excess of energy or mass (or both). In order to reach a stable state, they release that extra energy or mass in the form of radiation. Ionising radiation describes the particles and electromagnetic radiations that have sufficient energy to cause ionisation as they interact with matter.

Alpha particles have little penetrating power, and can be blocked by a barrier as thin as a sheet of paper. However, they can cause significant cell damage and potential health risks if ingested or inhaled, because of the large amounts of energy deposited in short distances in tissues. Beta particles have slightly more penetrating power, but can be stopped by shielding from metal such as aluminium. In contrast, gamma radiation is penetrating electromagnetic radiation that can pass through most shielding (though stopped by dense materials such as lead or thick concrete).

There are different units of measurement for radiation.

First, the activity of radioactive material is the rate at which radioactive decay takes place. It is measured in Becquerels (Bq), an international standard unit where 1 Bq is defined as one disintegration per second.

Second, measurements that reflect the different amounts of radiation energy absorbed by a mass of material are measured in rad or gray (Gy).

Third, other units measure the relative biological damage in the human body. In the 1950s, many countries used the measurement rem (R), but today, the sievert (Sv) is the standard unit to measure the health effect of low levels of ionising radiation on the human body. Small doses of radiation are measured in millisievert (mSv).

As a rough guide, 1 rad = 0.01 Gy = 10 mGy and, similarly, 1 rem = 0.01 Sv = 10 mSv.

There is no accepted threshold below which there is no risk of cancer induction. The risk diminishes with a diminishing dose, but is not eliminated. Risk is cumulative over time with the dose. Regulatory dose limits reflect upper permitted (although not advisable) thresholds of exposures by workers and members of the public. For example, in many countries the legal limit for radiation exposure by nuclear workers is 50 mSv in any one year and 20 mSv per annum averaged over five years (by way of comparison, the average natural background radiation in the United States is 2.6 mSv). An acute radiation dose of 500 mSv or more can begin to cause symptoms of radiation poisoning.

Half-life is the time in which radioactivity will decline to half its initial value through decay. Some radioactive isotopes are long-lasting, such as plutonium-239 with a half-life of 24,400 years. Other isotopes have relatively short half-lives, but can affect people’s health when they are exposed to high-level doses in a short period (such as the way radioactive iodine-131, with a half-life of just eight days, which can be rapidly absorbed by the thyroid gland, poses a particular threat to children).

Ionisation in the human body may cause cellular damage that leads to the death of a cell, or the cell may be damaged in such a way that it cannot reproduce or fulfil its original function.

Where there is DNA damage in the nucleus of the cell, damaged cells may continue to reproduce and develop into cancer, after an interval (latent period) from a few years to many decades.

There is also a documented association between exposure to ionising radiation and adverse impacts including, but not limited to, reproductive health including effects on the developing embryo and foetus; cardiovascular diseases; cataracts; and immunological diseases.

Previous Next