When was the first nuclear weapon created?
History of nuclear weapons
In January 1933, Adolf Hitler was appointed Chancellor of Germany and it quickly became unsafe for Jewish scientists to remain in the country. Leó Szilárd fled to London where he proposed, and in 1934 patented, the idea of a nuclear chain reaction via neutrons. The patent also introduced the term critical mass to describe the minimum amount of material required to sustain the chain reaction and its potential to cause an explosion. (British patent 630,726.) He subsequently assigned the patent to the British Admiralty so that it could be covered by the Official Secrets Act. In a very real sense, Szilárd was the father of the atomic bomb academically.
Also in 1934, Irène and Frédéric Joliot-Curie discovered that artificial radioactivity could be induced in stable elements by bombarding them with alpha particles; Enrico Fermi reported similar results when bombarding uranium with neutrons.
Nuclear warfare
After the successful Trinity nuclear test July 16, 1945, which was the very first nuclear detonation, the Manhattan project lead manager J. Robert Oppenheimer recalled:
Immediately after the atomic bombings of Japan, the status of atomic weapons in international and military relations was unclear. Presumably, the United States hoped atomic weapons could offset the Soviet Union's larger conventional ground forces in Eastern Europe, and possibly be used to pressure Soviet leader Joseph Stalin into making concessions. Under Stalin, the Soviet Union pursued its own atomic capabilities through a combination of scientific research and espionage directed against the American program. The Soviets believed that the Americans, with their limited nuclear arsenal, were unlikely to engage in any new world wars, while the Americans were not confident they could prevent a Soviet takeover of Europe, despite their atomic advantage.
History of the anti-nuclear movement
Radioactive fallout from nuclear weapons testing was first drawn to public attention in 1954 when a Hydrogen bomb test in the Pacific contaminated the crew of the Japanese fishing boat "Lucky Dragon". One of the fishermen died in Japan seven months later. The incident caused widespread concern around the world and "provided a decisive impetus for the emergence of the anti-nuclear weapons movement in many countries". The anti-nuclear weapons movement grew rapidly because for many people the atomic bomb "encapsulated the very worst direction in which society was moving".
Soviet atomic bomb project
The Soviets started experimenting with nuclear technology in 1943, and first tested a nuclear weapon in August 1949. Many of the fission based devices left behind radioactive isotopes which have contaminated air, water and soil in the areas immediately surrounding, downwind and downstream of the blast site. According to the records that the Russian government released in 1991, the Soviet Union tested 969 nuclear devices between 1949 and 1990. Soviet scientists conducted the tests with little regard for environmental and public health consequences. The detrimental effects that the toxic waste generated by weapons testing and processing of radioactive materials are still felt to this day. Even decades later, the risk of developing various types of cancer, especially that of the thyroid and the lungs, continues to be elevated far above national averages for people in affected areas. Iodine-131, a radioactive isotope that is a major byproduct of fission-based weapons, is retained in the thyroid gland, and so poisoning of this kind is commonplace in impacted populations.
K-25
The discovery of the neutron by James Chadwick in 1932, followed by that of nuclear fission in uranium by the German chemists Otto Hahn and Fritz Strassmann in 1938, and its theoretical explanation (and naming) by Lise Meitner and Otto Frisch soon after, opened up the possibility of a controlled nuclear chain reaction with uranium. At the Pupin Laboratories at Columbia University, Enrico Fermi and Leo Szilard began exploring how this might be achieved. Fears that a German atomic bomb project would develop atomic weapons first, especially among scientists who were refugees from Nazi Germany and other fascist countries, were expressed in the Einstein-Szilard letter to the President of the United States, Franklin D. Roosevelt. This prompted Roosevelt to initiate preliminary research in late 1939.
20th-century events
Nuclear weapons brought an entirely new and terrifying possibility to warfare: a nuclear holocaust. While at first the United States held a monopoly on the production of nuclear weapons, the Soviet Union, with some assistance from espionage, managed to detonate its first weapon (dubbed "Joe-1" by the West) in August 1949. The post-war relations between the two, which had already been deteriorating, began to rapidly disintegrate. Soon the two were locked in a massive stockpiling of nuclear weapons. The United States began a crash program to develop the first hydrogen bomb in 1950, and detonated its first thermonuclear weapon in 1952. This new weapon was alone over 400 times as powerful as the weapons used against Japan. The Soviet Union detonated a primitive thermonuclear weapon in 1953 and a full-fledged one in 1955.
Japanese nuclear weapon program
In 1934, Tohoku University professor Hikosaka Tadayoshi's "atomic physics theory" was released. Hikosaka pointed out the huge energy contained by nuclei and the possibility that both nuclear power generation and weapons could be created.
In December 1938, the German chemists Otto Hahn and Fritz Strassmann sent a manuscript to "Naturwissenschaften" reporting that they had detected the element barium after bombarding uranium with neutrons; simultaneously, they communicated these results to Lise Meitner. Meitner, and her nephew Otto Robert Frisch, correctly interpreted these results as being nuclear fission and Frisch confirmed this experimentally on 13 January 1939. Physicists around the world immediately realized that chain reactions could be produced and notified their governments of the possibility of developing nuclear weapons.
Nuclear weapons and Israel
According to a 2013 report by the "Bulletin of the Atomic Scientists", which cited US Defense Intelligence Agency figures, Israel began the production of nuclear weapons in 1967, when it produced its first two nuclear bombs. According to the report's calculations, Israel produced nuclear weapons at an average rate of two per year, and stopped production in 2004. The report stated that Israel has 80 nuclear warheads and has enough fissile material to produce 190 more. In 2014, former US president Jimmy Carter stated that "Israel has, what, 300 or more, nobody knows exactly how many" nuclear weapons.
Nuclear weapon
In the late 1940s, lack of mutual trust prevented the United States and the Soviet Union from making progress on arms control agreements. The Russell–Einstein Manifesto was issued in London on July 9, 1955, by Bertrand Russell in the midst of the Cold War. It highlighted the dangers posed by nuclear weapons and called for world leaders to seek peaceful resolutions to international conflict. The signatories included eleven pre-eminent intellectuals and scientists, including Albert Einstein, who signed it just days before his death on April 18, 1955. A few days after the release, philanthropist Cyrus S. Eaton offered to sponsor a conference—called for in the manifesto—in Pugwash, Nova Scotia, Eaton's birthplace. This conference was to be the first of the Pugwash Conferences on Science and World Affairs, held in July 1957.
History of Western civilization
The world lived in the constant fear of World War III in the Cold War. Seemingly any conflict involving Communism might lead to a conflict between the Warsaw pact countries and the NATO countries. The prospect of a third world war was made even more frightening by the fact that it would almost certainly be a nuclear war. In 1949 the Soviets developed their first atomic bomb, and soon both the United States and Soviet Union had enough to destroy the world several times over. With the development of missile technology, the stakes were raised as either country could launch weapons from great distances across the globe to their targets. Eventually, Britain, France, and China would also develop nuclear weapons. It is believed that Israel developed nuclear weapons as well.
Third and fourth terms of the presidency of Franklin D. Roosevelt
In August 1939, Leo Szilard and Albert Einstein sent the Einstein–Szilárd letter to Roosevelt, warning of the possibility of a German project to develop nuclear weapons. Szilard realized that the recently discovered process of nuclear fission could be used to create a nuclear chain reaction that could be used as a weapon of mass destruction. Roosevelt feared the consequences of allowing Germany to have sole possession of the technology, and authorized preliminary research into nuclear weapons. After the attack on Pearl Harbor, the Roosevelt administration secured the funds needed to continue research and selected General Leslie Groves to oversee the Manhattan Project, which was charged with developing the first nuclear weapons. Roosevelt and Churchill agreed to jointly pursue the project with the Quebec Agreement, and Roosevelt helped ensure that American scientists cooperated with their British counterparts. The Manhattan Project cost more than $2 billion, employed 150,000 individuals, and spurred the construction of massive facilities at Oak Ridge, Los Alamos, and other parts of the country.
History of nuclear weapons
By the time Nazi Germany invaded Poland in 1939, beginning World War II, many of Europe's top scientists had already fled the imminent conflict. Physicists on both sides were well aware of the possibility of utilizing nuclear fission as a weapon, but no one was quite sure how it could be done. 
In August 1939, concerned that Germany might have its own project to develop fission-based weapons, Albert Einstein signed a letter to U.S. President Franklin D. Roosevelt warning him of the threat. Roosevelt responded by setting up the Uranium Committee under Lyman James Briggs but, with little initial funding ($6,000), progress was slow. It was not until the Japanese attack on Pearl Harbor in December, 1941, that the U.S. decided to commit the necessary resources.
Nuclear technology
Since these bombings, no nuclear weapons have been deployed offensively. Nevertheless, they prompted an arms race to develop increasingly destructive bombs to provide a nuclear deterrent. Just over four years later, on August 29, 1949, the Soviet Union detonated its first fission weapon. The United Kingdom followed on October 2, 1952; France, on February 13, 1960; and China component to a nuclear weapon. Approximately half of the deaths from Hiroshima and Nagasaki died two to five years afterward from radiation exposure. A radiological weapons is a type of nuclear weapon designed to distribute hazardous nuclear material in enemy areas. Such a weapon would not have the explosive capability of a fission or fusion bomb, but would kill many people and contaminate a large area. A radiological weapon has never been deployed. While considered useless by a conventional military, such a weapon raises concerns over nuclear terrorism.
Nuclear weapons testing
The first nuclear device was detonated as a test by the United States at the Trinity site on July 16, 1945, with a yield approximately equivalent to 20 kilotons of TNT. The first thermonuclear weapon technology test of engineer 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 megatons.
Nuclear power
Electricity was generated for the first time by a nuclear reactor on December 20, 1951, at the EBR-I experimental station near Arco, Idaho, which initially produced about 100 kW.
In 1953, American President Dwight Eisenhower gave his "Atoms for Peace" speech at the United Nations, emphasizing the need to develop "peaceful" uses of nuclear power quickly. This was followed by the 1954 Amendments to the Atomic Energy Act which allowed rapid declassification of U.S. reactor technology and encouraged development by the private sector.
History of nuclear weapons
The notion of using a fission weapon to ignite a process of nuclear fusion can be dated back to 1942. At the first major theoretical conference on the development of an atomic bomb hosted by J. Robert Oppenheimer at the University of California, Berkeley, participant Edward Teller directed the majority of the discussion towards Enrico Fermi's idea of a "Super" bomb that would use the same reactions that powered the Sun itself.
Duck and Cover (film)
After nuclear weapons were developed (the first having been developed during the Manhattan Project during World War II), it was realized what kind of danger they posed. The United States held a nuclear monopoly from the end of World War II until 1949, when the Soviets detonated their first nuclear device.
Project Y
The discovery of the neutron by James Chadwick in 1932, followed by that of nuclear fission by German chemists Otto Hahn and Fritz Strassmann in 1938, and its theoretical explanation (and naming) by Lise Meitner and Otto Frisch soon after, opened up the possibility of a controlled nuclear chain reaction using uranium. At the time, few scientists in the United States thought that an atomic bomb was practical, but the possibility that a German atomic bomb project would develop atomic weapons sufficiently concerned scientists who were refugees from Nazi Germany and other fascist countries, that they drafted the Einstein–Szilard letter to warn President Franklin D. Roosevelt. This prompted preliminary research in the United States, beginning in late 1939.
Progress was slow in the United States, but in Britain, Otto Frisch and Rudolf Peierls, two refugee physicists from Germany at the University of Birmingham, examined the theoretical issues involved in developing, producing and using atomic bombs. They considered what would happen to a sphere of pure uranium-235, and found that not only could a chain reaction occur, but it might require as little as of uranium-235 to unleash the energy of hundreds of tons of TNT. Their superior, Mark Oliphant, took the Frisch–Peierls memorandum to Sir Henry Tizard, the chairman of the Committee for the Scientific Survey of Air Warfare (CSSAW), who in turn passed it on to George Paget Thomson, to whom the CSSAW had delegated responsibility for uranium research. CSSAW created the MAUD Committee to investigate. In its final report in July 1941, the MAUD Committee concluded that an atomic bomb was not only feasible, but might be produced as early as 1943. In response, the British government created a nuclear weapons project known as Tube Alloys.
Red Beard (nuclear weapon)
Red Beard was the first British tactical nuclear weapon. It was carried by the English Electric Canberra and the V bombers of the Royal Air Force (RAF), and by the Blackburn Buccaneers, Sea Vixens, and Supermarine Scimitars of the Royal Navy's (RN) Fleet Air Arm (FAA). Developed to Operational Requirement 1127 (OR.1127), it was introduced in 1961, entered service in 1962. It was replaced by the WE.177 in the early 1970s and was withdrawn in 1971.
Armed Forces Special Weapons Project
Nuclear weapons were developed during World War II by the Manhattan Project, a major research and development effort led by the United States, with participation from the United Kingdom and Canada. From 1942 to 1946, it was under the direction of Major General Leslie R. Groves, Jr., of the US Army Corps of Engineers. It created a network of production facilities, most notably for uranium enrichment at Oak Ridge, Tennessee, plutonium production at Hanford, Washington and weapons research and design at the Los Alamos Laboratory in Los Alamos, New Mexico. The nuclear weapons that were developed were used in the atomic bombings of Hiroshima and Nagasaki in August 1945.
List of states with nuclear weapons
The United Kingdom tested its first nuclear weapon ("Hurricane") in 1952. The UK had provided considerable impetus and initial research for the early conception of the atomic bomb, aided by Austrian, German and Polish physicists working at British universities who had either fled or decided not to return to Nazi Germany or Nazi controlled territories. The UK collaborated closely with the United States and Canada during the Manhattan Project, but had to develop its own method for manufacturing and detonating a bomb as U.S. secrecy grew after 1945. The United Kingdom was the third country in the world, after the United States and Soviet Union, to develop and test a nuclear weapon. Its programme was motivated to have an independent deterrent against the Soviet Union, while also maintaining its status as a great power. It tested its first hydrogen bomb in 1957 (Operation Grapple), making it the third country to do so after the United States and Soviet Union. The UK maintained a fleet of V bomber strategic bombers and ballistic missile submarines (SSBNs) equipped with nuclear weapons during the Cold War. It currently maintains a fleet of four 'Vanguard' class ballistic missile submarines equipped with Trident II missiles. In 2016, the UK House of Commons voted to renew the British nuclear weapons system with the "Dreadnought"-class submarine, without setting a date for the commencement of service of a replacement to the current system.
Rubby Sherr
Rubby Sherr (September 14, 1913 – July 8, 2013) was an American nuclear physicist who co-invented a key component of the first nuclear weapon while participating in the Manhattan Project during the Second World War. His academic career spanned nearly eight decades, including almost 40 years working at Princeton University.
Military history of Jewish Americans
America's rise as a nuclear power resulted directly from the Manhattan Project, codename for a project during World War II to develop the first atomic bombs for wartime use. The project's roots began in 1939 when, at the urging of Leó Szilárd, Albert Einstein signed the Einstein–Szilárd letter to US president Franklin D. Roosevelt expressing his concerns that Nazi Germany may be trying to develop nuclear weapons.
Uranium
The 1789 discovery of uranium in the mineral pitchblende is credited to Martin Heinrich Klaproth, who named the new element after the recently discovered planet Uranus. Eugène-Melchior Péligot was the first person to isolate the metal and its radioactive properties were discovered in 1896 by Henri Becquerel. Research by Otto Hahn, Lise Meitner, Enrico Fermi and others, such as J. Robert Oppenheimer starting in 1934 led to its use as a fuel in the nuclear power industry and in "Little Boy", the first nuclear weapon used in war. An ensuing arms race during the Cold War between the United States and the Soviet Union produced tens of thousands of nuclear weapons that used uranium metal and uranium-derived plutonium-239. The security of those weapons and their fissile material following the breakup of the Soviet Union in 1991 is an ongoing concern for public health and safety. See Nuclear proliferation.
Nuclear weapons and Israel
The State of Israel is widely believed to possess nuclear weapons. Current estimates put the size of the Israeli nuclear arsenal at between 80 and 400 nuclear warheads, and the country is believed to possess the ability to deliver them in a variety of methods including: aircraft; submarine-launched cruise missiles; and the Jericho series of intermediate to intercontinental range ballistic missiles. Its first deliverable nuclear weapon is thought to have been created in late 1966 or early 1967; which would make it the sixth country in the world to have developed them.
History of nuclear weapons
H. G. Wells was inspired to write about atomic weapons in a 1914 novel, "The World Set Free", which appeared shortly before the First World War.
In a 1924 article, Winston Churchill speculated about the possible military implications: "Might not a bomb no bigger than an orange be found to possess a secret power to destroy a whole block of buildings—nay to concentrate the force of a thousand tons of cordite and blast a township at a stroke?"
Charles de Gaulle
As early as April 1954 while out of power, de Gaulle argued that France must have its own nuclear arsenal; at the time nuclear weapons were seen as a national status symbol and a way of maintaining international prestige with a place at the 'top table' of the United Nations. Full-scale research began again in late 1954 when Prime Minister Pierre Mendès France authorized a plan to develop the atomic bomb; large deposits of uranium had been discovered near Limoges in central France, providing the researchers with an unrestricted supply of nuclear fuel. France's independent Force de Frappe (strike force) came into being soon after de Gaulle's election with his authorization for the first nuclear test.
Nuclear arms race
The first nuclear weapon was created by the United States of America. During the Second World War and was developed to be used against the Axis powers. Scientists of the Soviet Union were aware of the potential of nuclear weapons and had also been conducting research on the field.
Pre-emptive nuclear strike
In the immediate aftermath of World War II, the leadership of the Soviet Union feared the United States would use its nuclear superiority to its advantage, as from 1945 to 1948 the U.S. was the only state possessing nuclear weapons. The USSR countered by rapidly developing their own nuclear weapons, surprising the US with their first test in 1949. In turn, the U.S. countered by developing the vastly more powerful thermonuclear weapon, testing their first hydrogen bomb in 1952 at Ivy Mike, but the USSR quickly countered by testing their own thermonuclear weapons, with a test in 1953 of a semi-thermonuclear weapon of the Sloika design, and in 1956, with the testing of Sakharov's Third Idea – equivalent to the Castle Bravo device. Meanwhile, tensions between the two nations rose as 1956 saw the suppression of Hungary by the Soviets; the U.S. and European nations drew certain conclusions from that event, while in the U.S., a powerful social backlash was afoot, prompted by Senator Joseph McCarthy, the House Un-American Activities Committee, and Julius and Ethel Rosenberg, U.S. citizens executed in 1953 after conviction of espionage. This atmosphere was further inflamed by the 1957 launch of Sputnik, which led to fears of Communists attacking from outer space, as well as concerns that if the Soviets could launch a device into orbit, they could equally cause a device to re-enter the atmosphere and impact any part of the planet. John F. Kennedy capitalized on this situation by emphasizing the Bomber gap and the Missile gap, areas in which the Soviets were (inaccurately) perceived as leading the United States, while heated Soviet rhetoric added to political pressure. The 1960 U-2 incident, involving Francis Gary Powers, as well as the Berlin Crisis, along with the test of the Tsar Bomba, escalated tensions still further.
Nuclear weapons debate
Even before the first nuclear weapons had been developed, scientists involved with the Manhattan Project were divided over the use of the weapon. Some—notably a number at the University of Chicago Metallurgical Laboratory, represented in part by Leó Szilárd—lobbied early on that the atomic bomb should only be built as a deterrent against Nazi Germany getting a bomb, and should not be used against populated cities. The Franck Report argued in June 1945 that instead of being used against a city, the first atomic bomb should be "demonstrated" to the Japanese on an uninhabited area. This recommendation was not agreed with by the military commanders, the Los Alamos Target Committee (made up of other scientists), or the politicians who had input into the use of the weapon. Because the Manhattan Project was considered to be "top secret", there was no public discussion of the use of nuclear arms, and even within the U.S. government, knowledge of the bomb was extremely limited.
History of nuclear weapons
As a show of political strength, the Soviet Union tested the largest-ever nuclear weapon in October 1961, the massive Tsar Bomba, which was tested in a reduced state with a yield of around 50 megatons—in its full state it was estimated to have been around 100 Mt. The weapon was largely impractical for actual military use, but was hot enough to induce third-degree burns at a distance of 62 mi (100 km) away. In its full, dirty, design it would have increased the amount of worldwide fallout since 1945 by 25%.
History of nuclear weapons
The first atomic bombs dropped on Hiroshima and Nagasaki were large, custom-made devices, requiring highly trained personnel for their arming and deployment. They could be dropped only from the largest bomber planes—at the time the B-29 Superfortress—and each plane could only carry a single bomb in its hold.
Presidency of Franklin D. Roosevelt
In August 1939, Leo Szilard and Albert Einstein sent the Einstein–Szilárd letter to Roosevelt, warning of the possibility of a German project to develop nuclear weapons. Szilard realized that the recently discovered process of nuclear fission could be used to create a nuclear chain reaction that could be used as a weapon of mass destruction. Roosevelt feared the consequences of allowing Germany to have sole possession of the technology, and authorized preliminary research into nuclear weapons. After the attack on Pearl Harbor, the Roosevelt administration secured the funds needed to continue research and selected General Leslie Groves to oversee the Manhattan Project, which was charged with developing the first nuclear weapons. Roosevelt and Churchill agreed to jointly pursue the project with the Quebec Agreement, and Roosevelt helped ensure that American scientists cooperated with their British counterparts.
Nuclear power plant
Electricity was generated by a nuclear reactor for the first time ever on September 3, 1948 at the X-10 Graphite Reactor in Oak Ridge, Tennessee in the United States, which was the first nuclear power station to power a light bulb. The second, larger experiment occurred on December 20, 1951 at the EBR-I experimental station near Arco, Idaho in the United States. On June 27, 1954, the world's first nuclear power station to generate electricity for a power grid started operations at the Soviet city of Obninsk. The world's first full scale power station, Calder Hall in England, opened on October 17, 1956. The world's first full scale power station solely devoted to electricity production (Calder Hall was also meant to produce plutonium), Shippingport power plant in the United States, connected to the grid on December 18, 1957.
History of nuclear weapons
The atomic bombings of Hiroshima and Nagasaki and the end of World War II quickly followed the 1945 Trinity nuclear test, and the Little Boy device was detonated over the Japanese city of Hiroshima on 6 August 1945. Exploding with a yield equivalent to 12,500 tonnes of TNT, the blast and thermal wave of the bomb destroyed nearly 50,000 buildings and killed approximately 75,000 people. Subsequently, the world’s nuclear weapons stockpiles grew.
Uranium
Two major types of atomic bombs were developed by the United States during World War II: a uranium-based device (codenamed "Little Boy") whose fissile material was highly enriched uranium, and a plutonium-based device (see Trinity test and "Fat Man") whose plutonium was derived from uranium-238. The uranium-based Little Boy device became the first nuclear weapon used in war when it was detonated over the Japanese city of Hiroshima on 6 August 1945. Exploding with a yield equivalent to 12,500 tonnes of TNT, the blast and thermal wave of the bomb destroyed nearly 50,000 buildings and killed approximately 75,000 people (see Atomic bombings of Hiroshima and Nagasaki). Initially it was believed that uranium was relatively rare, and that nuclear proliferation could be avoided by simply buying up all known uranium stocks, but within a decade large deposits of it were discovered in many places around the world.
Yakov Zeldovich
In 1949, Zeldovich led a team of physicists that conducted the first nuclear test, the RDS-1, based roughly on the American design obtained through the atomic spies in the United States, though he continued his fundamental work on explosive theory. Zeldovich then began working on modernizing the successive designs of the nuclear weapon and initially conceived the idea of hydrogen bomb to Andrei Sakharov and others. In the course of his work on nuclear weapons, Zeldovich did ground-breaking work in radiation hydrodynamics, and the physics of matter at high pressure.
First Chief Directorate
One of the biggest successes of Soviet foreign intelligence was the penetration of the American Manhattan Project, which was the code name for the effort during World War II to develop the first nuclear weapons of the United States with assistance from the United Kingdom and Canada. Information gathered in the United States, Great Britain and Canada, especially in USA, by NKVD and NKGB agents then supplied to Soviet physicists, allowed them to carry out the first Soviet nuclear explosion already in 1949.
Nuclear warfare
So far, two nuclear weapons have been used in the course of warfare, both by the United States near the end of World War II. On August 6, 1945, a uranium gun-type device (code name "Little Boy") was detonated over the Japanese city of Hiroshima. Three days later, on August 9, a plutonium implosion-type device (code name "Fat Man") was detonated over the Japanese city of Nagasaki. These two bombings resulted in the deaths of approximately 120,000 people.
Nuclear weapons of the United States
The United States was the first country to manufacture nuclear weapons and is the only country to have used them in combat, with the separate bombings of Hiroshima and Nagasaki in World War II. Before and during the Cold War, it conducted over a thousand nuclear tests and tested many long-range nuclear weapons delivery systems.
Nuclear Holocausts: Atomic War in Fiction
Nuclear Holocausts: Atomic War in Fiction, 1895–1984 was written by Paul Brians and published in 1987. This comprehensive study covers nuclear holocaust fiction published in English-language works between 1895 and 1984. Brians notes that 1895 marked the first appearance of an atomic weapon in fiction: Robert Cromie's "Crack of Doom". The latter date marks the conclusion of this study's time span.
History of nuclear weapons
An improved version of 'Fat Man' was developed, and on 26 February 1952, Prime Minister Winston Churchill announced that the United Kingdom also had an atomic bomb and a successful test took place on 3 October 1952. At first these were free-fall bombs, intended for use by the V Force of jet bombers. A Vickers Valiant dropped the first UK nuclear weapon on 11 October 1956 at Maralinga, South Australia. Later came a missile, Blue Steel, intended for carriage by the V Force bombers, and then the Blue Streak medium-range ballistic missile (later canceled). Anglo-American cooperation on nuclear weapons was restored by the 1958 US-UK Mutual Defence Agreement. As a result of this and the Polaris Sales Agreement, the United Kingdom has bought United States designs for submarine missiles and fitted its own warheads. It retains full independent control over the use of the missiles. It no longer possesses any free-fall bombs.
Nuclear artillery
United States developments resulted in nuclear weapons for various artillery systems, after the short-lived M65 Atomic Cannon standard howitzers were used. Delivery systems include, in approximate order of development:
The first artillery test was on May 25, 1953 at the Nevada Test Site. Fired as part of Operation Upshot–Knothole and codenamed "Shot GRABLE", a 280 mm (11 inch) shell with a gun-type fission warhead was fired 10,000 m (6.2 miles) and detonated 160 m (525 ft) above the ground with an estimated yield of 15 kilotons. This was the only nuclear artillery shell ever actually fired in the U.S. nuclear weapons test program. The shell was 1384 mm (4.5 ft) long and weighed 365 kg (805 lb). It was fired from a special, very large artillery piece, nicknamed "Atomic Annie", built by the Artillery Test Unit of Fort Sill, Oklahoma. About 3,200 soldiers and civilians were present. The warhead was designated the W9 nuclear warhead and 80 were produced in 1952 to 1953 for the T-124 shell. It was retired in 1957.
Weapon
World War II however, perhaps marked the most frantic period of weapons development in the history of humanity. Massive numbers of new designs and concepts were fielded, and all existing technologies were improved between 1939 and 1945. The most powerful weapon invented during this period was the atomic bomb, however many other weapons influenced the world in ways overshadowed by the importance of nuclear weapons.
20th-century events
During the 1930s, innovations in physics made it apparent that it could be possible to develop nuclear weapons of incredible power using nuclear reactions. When World War II broke out, scientists and advisors among the Allies feared that Nazi Germany may have been trying to develop its own atomic weapons, and the United States and the United Kingdom pooled their efforts in what became known as the Manhattan Project to beat them to it. At the secret Los Alamos laboratory in New Mexico, scientist Robert Oppenheimer led a team of the world's top scientists to develop the first nuclear weapons, the first of which was tested at the Trinity site in July 1945. However, Germany had surrendered in May 1945, and it had been discovered that the German atomic bomb program had not been very close to success.The Allied team produced two nuclear weapons for use in the war, one powered by uranium-235 and the other by plutonium as fissionable material, named "Little Boy" and "Fat Man". These were dropped on the Japanese cities of Hiroshima and Nagasaki on August 6 and 9, 1945 each. This, in combination with the Soviet invasion of Japanese-controlled territory, convinced the Japanese government to surrender unconditionally. These two weapons remain the only two nuclear weapons ever used against other countries in war.
History of nuclear weapons
In 1956, France formed a secret Committee for the Military Applications of Atomic Energy and a development program for delivery vehicles. With the return of Charles de Gaulle to the French presidency in 1958, final decisions to build a bomb were made, which led to a successful test in 1960. Since then, France has developed and maintained its own nuclear deterrent independent of NATO.
History of nuclear weapons
Peace movements emerged in Japan and in 1954 they converged to form a unified "Japanese Council Against Atomic and Hydrogen Bombs". Japanese opposition to the Pacific nuclear weapons tests was widespread, and "an estimated 35 million signatures were collected on petitions calling for bans on nuclear weapons". The Russell–Einstein Manifesto was issued in London on July 9, 1955 by Bertrand Russell in the midst of the Cold War. It highlighted the dangers posed by nuclear weapons and called for world leaders to seek peaceful resolutions to international conflict. The signatories included eleven pre-eminent intellectuals and scientists, including Albert Einstein, who signed it just days before his death on April 18, 1955. A few days after the release, philanthropist Cyrus S. Eaton offered to sponsor a conference—called for in the manifesto—in Pugwash, Nova Scotia, Eaton's birthplace. This conference was to be the first of the Pugwash Conferences on Science and World Affairs, held in July 1957.
Treaty on the Non-Proliferation of Nuclear Weapons
"Article IX": "For the purposes of this Treaty, a nuclear-weapon State is one which has manufactured and exploded a nuclear weapon or other nuclear explosive device prior to 1 January 1967."
Thermonuclear weapon
The first full-scale thermonuclear test was carried out by the United States in 1952; the concept has since been employed by most of the world's nuclear powers in the design of their weapons. The design of all modern thermonuclear weapons in the United States is known as the "Teller–Ulam configuration" for its two chief contributors, Edward Teller and Stanislaw Ulam, who developed it in 1951 for the United States, with certain concepts developed with the contribution of physicist John von Neumann. Similar devices were developed by the Soviet Union, United Kingdom, France, and China.
Nuclear weapons debate
The nuclear weapons debate refers to the controversies surrounding the threat, use and stockpiling of nuclear weapons. Even before the first nuclear weapons had been developed, scientists involved with the Manhattan Project were divided over the use of the weapon. The only time nuclear weapons have been used in warfare was during the final stages of World War II when United States Army Air Forces B-29 Superfortress bombers dropped atomic bombs on the Japanese cities of Hiroshima and Nagasaki in early August 1945. The role of the bombings in Japan's surrender and the U.S.'s ethical justification for them have been the subject of scholarly and popular debate for decades.
Nuclear disarmament refers both to the act of reducing or eliminating nuclear weapons and to the end state of a nuclear-free world. Proponents of disarmament typically condemn a priori the threat or use of nuclear weapons as immoral and argue that only total disarmament can eliminate the possibility of nuclear war. Critics of nuclear disarmament say that it would undermine deterrence and make conventional wars more likely, more destructive, or both. The debate becomes considerably complex when considering various scenarios for example, total vs partial or unilateral vs multilateral disarmament.
Nuclear weapons of the United States
The initial U.S. nuclear program was run by the National Bureau of Standards starting in 1939 under the edict of President Franklin Delano Roosevelt. Its primary purpose was to delegate research and dispense funds. In 1940 the National Defense Research Committee (NDRC) was established, coordinating work under the Committee on Uranium among its other wartime efforts. In June 1941, the Office of Scientific Research and Development (OSRD) was established, with the NDRC as one of its subordinate agencies, which enlarged and renamed the Uranium Committee as the Section on Uranium. In 1941, NDRC research was placed under direct control of Vannevar Bush as the OSRD S-1 Section, which attempted to increase the pace of weapons research. In June 1942, the U.S. Army Corps of Engineers took over the project to develop atomic weapons, while the OSRD retained responsibility for scientific research.
Nuclear espionage
During the Manhattan Project, the joint effort during World War II by the United States, the United Kingdom, and Canada to create the first nuclear weapons, there were many instances of nuclear espionage in which project scientists or technicians channeled information about bomb development and design to the Soviet Union. These people are often referred to as the Atomic Spies, and their work continued into the early Cold War. Because most of these cases became well known in the context of the anti-Communist 1950s, there has been long-standing dispute over the exact details of these cases, though some of this was settled with the making public of the Venona project transcripts, which were intercepted and decrypted messages between Soviet agents and the Soviet government. Some issues remain unsettled, however.
The Dark Frontier
Based on the development of weaponry in the year 1936, "The Dark Frontier" was one of the first novels to predict the invention of a nuclear bomb and its consequences. Ambler evidently had no knowledge of what producing an atomic bomb may involve (even professional physicists at the time had only a vague idea). The book makes no mention of uranium or any other radioactive material, and makes instead the assumption that setting off an atomic bomb would involve a considerable electric charge. Still, Ambler could be credited with having become aware, before many others, of this coming weapon which was to have such a profound effect on the entire world, and his depiction of scientists in a secret hideout building such a bomb could be considered a preview of the Manhattan Project – and he correctly surmised that refugees from Nazi Germany might get involved in such a project.
Industrial warfare
The use of nuclear weapons first came into being during the last months of WWII, with the dropping of atomic bombs on Hiroshima and Nagasaki. This was the only use of nuclear weapons in combat. For a decade after World War II, the United States and later the Soviet Union (and to a lesser extent the United Kingdom and France) developed and maintained a strategic force of bombers that would be able to attack any potential aggressor from bases inside their countries.
Weapons in science fiction
Nuclear weapons are a staple element in science fiction novels. The phrase "atomic bomb" predates their existence, and dates back to H. G. Wells' "The World Set Free" (1914) when scientists had discovered that radioactive decay implied potentially limitless energy locked inside of atomic particles (Wells' atomic bombs were only as powerful as conventional explosives, but would continue exploding for days on end). Cleve Cartmill predicted a chain-reaction-type nuclear bomb in his 1944 science-fiction story "Deadline", which led to the FBI investigating him, due to concern over a potential breach of security on the Manhattan Project.
Nuclear Explosions for the National Economy
In November 1949, shortly after the test of their first nuclear device on September 23, 1949, Andrey Vyshinsky, the Soviet representative to the United Nations, delivered a statement justifying their efforts to develop their own nuclear weapons capability. He said:
Nuclear explosion
Since the Trinity test and excluding the combat use of nuclear weapons, mankind (those few nations with capability) has detonated roughly 1,700 nuclear explosions, all but 6 as tests. Of these, six were peaceful nuclear explosions. Nuclear tests are experiments carried out to determine the effectiveness, yield and explosive capability of nuclear weapons. Throughout the 20th century, most nations that have developed nuclear weapons had a staged test of them. Testing nuclear weapons can yield information about how the weapons work, as well as how the weapons behave under various conditions and how structures behave when subjected to a nuclear explosion. Additionally, nuclear testing has often been used as an indicator of scientific and military strength, and many tests have been overtly political in their intention; most nuclear weapons states publicly declared their nuclear status by means of a nuclear test.
British nuclear tests at Maralinga
On 3 October 1952, the United Kingdom tested its first nuclear weapon, named "Hurricane", at the Monte Bello Islands off the coast of Western Australia. A year later the first nuclear test on the Australian mainland was "Totem 1" () at Emu Field in the Great Victoria Desert, South Australia, on 15 October 1953. "Totem 2" () followed two weeks later on 27 October. The Supply Minister, Howard Beale, stated in 1955 that "England has the know how; we have the open spaces, much technical skill and a great willingness to help the Motherland. Between us we should help to build the defences of the free world, and make historic advances in harnessing the forces of nature."
George Koval
Koval was transferred from Oak Ridge to a top-secret lab in Dayton, Ohio on June 27, 1945, where polonium initiators were fabricated. The world's first atomic bomb was detonated in New Mexico on July 16 of that year. Atomic bombs were dropped on Japan on August 6 and 9, leading to Japan's surrender and the end of World War II. The Soviet Union responded by increasing efforts to develop its own atomic bomb. While the American Central Intelligence Agency estimated the Soviets would not succeed until 1950–53, the first Soviet atomic bomb was detonated on August 29, 1949. The initiator for the plutonium bomb was, according to Russian military officials, "prepared to the 'recipe' provided by military intelligence agent Delmar [Koval]".
Nuclear weapons of the United States
This was the beginning of the Manhattan Project, run as the Manhattan Engineering District (MED), an agency under military control that was in charge of developing the first atomic weapons. After World War II, the MED maintained control over the U.S. arsenal and production facilities and coordinated the Operation Crossroads tests. In 1946 after a long and protracted debate, the Atomic Energy Act of 1946 was passed, creating the Atomic Energy Commission (AEC) as a civilian agency that would be in charge of the production of nuclear weapons and research facilities, funded through Congress, with oversight provided by the Joint Committee on Atomic Energy. The AEC was given vast powers of control over secrecy, research, and money, and could seize lands with suspected uranium deposits. Along with its duties towards the production and regulation of nuclear weapons, it was also in charge of stimulating development and regulating civilian nuclear power. The full transference of activities was finalized in January 1947.
Nuclear arms race
In 1952, the United Kingdom became the third nation to possess nuclear weapons when it detonated an atomic bomb in Operation Hurricane on October 3, 1952, which had a yield of 25 kilotons. Despite major contributions to the Manhattan Project by both Canadian and British governments, the U.S. Congress passed the Atomic Energy Act of 1946, which prohibited multi-national cooperation on nuclear projects. The McMahon Act fueled resentment from British scientists and Winston Churchill, as they believed that there were agreements regarding post-war sharing of nuclear technology, and led to Britain developing its own nuclear weapons. Britain did not begin planning the development of their own nuclear weapon until January 1947. Because of Britain’s small size, they decided to test their bomb on the Monte Bello Islands, off the coast of Australia. Following this successful test, under the leadership of Churchill, Britain decided to develop and test a hydrogen bomb. The first successful hydrogen bomb test occurred on November 8, 1957, which had a yield of 1.8 megatons. An amendment to the Atomic Energy Act in 1958 allowed nuclear cooperation once again, and British-U.S. nuclear programs resumed. During the Cold War, British nuclear deterrence came from submarines and nuclear-armed aircraft. The Resolution class ballistic missile submarines armed with the American-built Polaris missile provided the sea deterrent, while aircraft such as the Avro Vulcan, SEPECAT Jaguar, Panavia Tornado and several other Royal Air Force strike aircraft carrying WE.177 gravity bomb provided the air deterrent.
Nuclear weapons of the United States
The United States first began developing nuclear weapons during World War II under the order of President Franklin Roosevelt in 1939, motivated by the fear that they were engaged in a race with Nazi Germany to develop such a weapon. After a slow start under the direction of the National Bureau of Standards, at the urging of British scientists and American administrators, the program was put under the Office of Scientific Research and Development, and in 1942 it was officially transferred under the auspices of the United States Army and became known as the Manhattan Project, an American, British and Canadian joint venture. Under the direction of General Leslie Groves, over thirty different sites were constructed for the research, production, and testing of components related to bomb-making. These included the Los Alamos National Laboratory at Los Alamos, New Mexico, under the direction of physicist Robert Oppenheimer, the Hanford plutonium production facility in Washington, and the Y-12 National Security Complex in Tennessee.
Atomic bombings of Hiroshima and Nagasaki
The discovery of nuclear fission by German chemists Otto Hahn and Fritz Strassmann in 1938, and its theoretical explanation by Lise Meitner and Otto Frisch, made the development of an atomic bomb a theoretical possibility. Fears that a German atomic bomb project would develop atomic weapons first, especially among scientists who were refugees from Nazi Germany and other fascist countries, were expressed in the Einstein-Szilard letter. This prompted preliminary research in the United States in late 1939. Progress was slow until the arrival of the British MAUD Committee report in late 1941, which indicated that only 5 to 10 kilograms of isotopically enriched uranium-235 were needed for a bomb instead of tons of natural uranium and a neutron moderator like heavy water.
List of states with nuclear weapons
The Soviet Union tested its first nuclear weapon ("RDS-1") in 1949. This crash project was developed partially with information obtained via espionage during and after World War II. The Soviet Union was the second nation to have developed and tested a nuclear weapon. The direct motivation for Soviet weapons development was to achieve a balance of power during the Cold War. It tested its first megaton-range hydrogen bomb ("RDS-37") in 1955. The Soviet Union also tested the most powerful explosive ever detonated by humans, ("Tsar Bomba"), with a theoretical yield of 100 megatons, intentionally reduced to 50 when detonated. After its dissolution in 1991, the Soviet weapons entered officially into the possession of the Russian Federation. The Soviet nuclear arsenal contained some 45,000 warheads at its peak (in 1986); the Soviet Union built about 55,000 nuclear warheads since 1949.
Soviet Union–United States relations
The Soviet Union detonated its first nuclear weapon in 1949, ending the United States' monopoly on nuclear weapons. The United States and the Soviet Union engaged in a conventional and nuclear arms race that persisted until the collapse of the Soviet Union. Andrei Gromyko was Minister of Foreign Affairs of the USSR, and is the longest-serving foreign minister in the world.
McDonald Ranch House
The McDonald Ranch House, also known as Trinity Site, in the Oscura Mountains of Socorro County, New Mexico, was the location of assembly of the world's first nuclear weapon. The active components of the Trinity test "gadget", a plutonium Fat Man-type bomb similar to that later dropped on Nagasaki, Japan, were assembled there on July 13, 1945. The completed bomb was winched up the test tower the following day and detonated on July 16, 1945 as the Trinity nuclear test.
History of nuclear weapons
Historians claim to have found a rough schematic showing a Nazi nuclear bomb. In March 1945, a German scientific team was directed by the physicist Kurt Diebner to develop a primitive nuclear device in Ohrdruf, Thuringia. Last ditch research was conducted in an experimental nuclear reactor at Haigerloch.
Nuclear arms race
France became the fourth nation to possess nuclear weapons on February 13, 1960, when the atomic bomb "Gerboise Bleue" was detonated in Algeria, then still a French colony [Formally a part of the Metropolitan France.] France began making plans for a nuclear-weapons program shortly after the Second World War, but the program did not actually begin until the late 1950s. Eight years later, France conducted its first thermonuclear test above Fangatuafa Atoll. It had a yield of 2.6 megatons. This bomb significantly contaminated the atoll with radiation for six years, making it off-limits to humans. During the Cold War, the French nuclear deterrent was centered around the Force de frappe, a nuclear triad consisting of Dassault Mirage IV bombers carrying such nuclear weapons as the AN-22 gravity bomb and the ASMP stand-off attack missile, Pluton and Hades ballistic missiles, and the Redoutable class submarine armed with strategic nuclear missiles.
History of nuclear weapons
The simplest form of nuclear weapon is a gun-type fission weapon, where a sub-critical mass would be shot at another sub-critical mass. The result would be a super-critical mass and an uncontrolled chain reaction that would create the desired explosion. The weapons envisaged in 1942 were the two gun-type weapons, Little Boy (uranium) and Thin Man (plutonium), and the Fat Man plutonium implosion bomb.
Nuclear history of the United States
Even before the first nuclear weapons had been developed, scientists involved with the Manhattan Project were divided over the use of the weapon. The role of the two atomic bombings of the country in Japan's surrender and the U.S.'s ethical justification for them has been the subject of scholarly and popular debate for decades. The question of whether nations should have nuclear weapons, or test them, has been continually and nearly universally controversial.
Trinity (nuclear test)
The creation of nuclear weapons arose from scientific and political developments of the 1930s. The decade saw many new discoveries about the nature of atoms, including the existence of nuclear fission. The concurrent rise of fascist governments in Europe led to a fear of a German nuclear weapon project, especially among scientists who were refugees from Nazi Germany and other fascist countries. When their calculations showed that nuclear weapons were theoretically feasible, the British and United States governments supported an all-out effort to build them.
History of nuclear weapons
On August 29, 1949, the effort brought its results, when the USSR tested its first fission bomb, dubbed "Joe-1" by the U.S., years ahead of American predictions. The news of the first Soviet bomb was announced to the world first by the United States, which had detected the nuclear fallout it generated from its test site in Kazakhstan.
Nuclear arms race
Behind the scenes, the Soviet government was working on building its own atomic weapons. During the war, Soviet efforts had been limited by a lack of uranium but new supplies in Eastern Europe were found and provided a steady supply while the Soviets developed a domestic source. While American experts had predicted that the Soviet Union would not have nuclear weapons until the mid-1950s, the first Soviet bomb was detonated on August 29, 1949, shocking the entire world. The bomb, named "First Lightning" by the West, was more or less a copy of "Fat Man", one of the bombs the United States had dropped on Japan in 1945.
Atomic Age
The Atomic Age, also known as the Atomic Era, is the period of history following the detonation of the first nuclear ("atomic") bomb, "Trinity", on July 16, 1945, during World War II. Although nuclear chain reactions had been hypothesized in 1933 and the first artificial self-sustaining nuclear chain reaction (Chicago Pile-1) had taken place in December 1942, the Trinity test and the ensuing bombings of Hiroshima and Nagasaki that ended World War II represented the first large-scale use of nuclear technology and ushered in profound changes in sociopolitical thinking and the course of technology development.
Nuclear weapon design
The first systematic exploration of nuclear weapon design concepts took place in mid-1942 at the University of California, Berkeley. Important early discoveries had been made at the adjacent Lawrence Berkeley Laboratory, such as the 1940 cyclotron-made production and isolation of plutonium. A Berkeley professor, J. Robert Oppenheimer, had just been hired to run the nation's secret bomb design effort. His first act was to convene the 1942 summer conference.
History of nuclear weapons
Nuclear weapons possess enormous destructive power from nuclear fission or combined fission and fusion reactions. Building on scientific breakthroughs made during the 1930s, the United States, the United Kingdom and Canada collaborated during World War II, in what was called the Manhattan Project, to counter the suspected Nazi German atomic bomb project. In August 1945, two fission bombs were dropped on Japan, standing to date as the only use of nuclear weapons in combat. The Soviet Union started development shortly thereafter with their own atomic bomb project, and not long after that both countries developed even more powerful fusion weapons known as "hydrogen bombs".
History of nuclear weapons
Although uranium-238 cannot be used for the initial stage of an atomic bomb, when it absorbs a neutron, it becomes uranium-239 which decays into neptunium-239, and finally the relatively stable plutonium-239, an element that does not exist naturally on Earth, but is fissile like uranium-235. After Fermi achieved the world's first sustained and controlled nuclear chain reaction with the creation of the first atomic pile, massive reactors were secretly constructed at what is now known as Hanford Site to transform uranium-238 into plutonium for a bomb.
Nuclear warfare
After World War II, nuclear weapons were also developed by the Soviet Union (1949), the United Kingdom (1952), France (1960), and the People's Republic of China (1964), which contributed to the state of conflict and extreme tension that became known as the Cold War. In 1974, India, and in 1998, Pakistan, two countries that were openly hostile toward each other, developed nuclear weapons. Israel (1960s) and North Korea (2006) are also thought to have developed stocks of nuclear weapons, though it is not known how many. The Israeli government has never admitted or denied to having nuclear weapons, although it is known to have constructed the reactor and reprocessing plant necessary for building nuclear weapons. South Africa also manufactured several complete nuclear weapons in the 1980s, but subsequently became the first country to voluntarily destroy their domestically made weapons stocks and abandon further production (1990s). Nuclear weapons have been detonated on over 2,000 occasions for testing purposes and demonstrations.
Nuclear weapons of the United States
Since this path was chosen, the United States was, in its early days, essentially an advocate for the prevention of nuclear proliferation, though primarily for the reason of self-preservation. A few years after the USSR detonated its first weapon in 1949, though, the U.S. under President Dwight D. Eisenhower sought to encourage a program of sharing nuclear information related to civilian nuclear power and nuclear physics in general. The Atoms for Peace program, begun in 1953, was also in part political: the U.S. was better poised to commit various scarce resources, such as enriched uranium, towards this peaceful effort, and to request a similar contribution from the Soviet Union, who had far fewer resources along these lines; thus the program had a strategic justification as well, as was later revealed by internal memos. This overall goal of promoting civilian use of nuclear energy in other countries, while also preventing weapons dissemination, has been labeled by many critics as contradictory and having led to lax standards for a number of decades which allowed a number of other nations, such as China and India, to profit from dual-use technology (purchased from nations other than the U.S.).
History of nuclear weapons
The first fusion bomb was tested by the United States in "Operation Ivy" on November 1, 1952, on Elugelab Island in the Enewetak (or Eniwetok) Atoll of the Marshall Islands, code-named "Mike." Mike used liquid deuterium as its fusion fuel and a large fission weapon as its trigger. The device was a prototype design and not a deliverable weapon: standing over 20 ft (6 m) high and weighing at least 140,000 lb (64 t) (its refrigeration equipment added an additional as well), it could not have been dropped from even the largest planes.
Nuclear weapon design
It is inherently dangerous to have a weapon containing a quantity and shape of fissile material which can form a critical mass through a relatively simple accident. Because of this danger, the propellant in Little Boy (four bags of cordite) was inserted into the bomb in flight, shortly after takeoff on August 6, 1945. This was the first time a gun-type nuclear weapon had ever been fully assembled.
History of nuclear weapons
In the end, President Truman made the final decision, looking for a proper response to the first Soviet atomic bomb test in 1949. On January 31, 1950, Truman announced a crash program to develop the hydrogen (fusion) bomb. At this point, however, the exact mechanism was still not known: the classical hydrogen bomb, whereby the "heat" of the fission bomb would be used to ignite the fusion material, seemed highly unworkable. However, an insight by Los Alamos mathematician Stanislaw Ulam showed that the fission bomb and the fusion fuel could be in separate parts of the bomb, and that "radiation" of the fission bomb could first work in a way to "compress" the fusion material before igniting it.
Nuclear weapons testing
The first atomic weapons test was conducted near Alamogordo, New Mexico, on July 16, 1945, during the Manhattan Project, and given the codename "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 nuclear explosion would be before they were used in combat against Japan. While the test gave a good approximation of many of the explosion's effects, it did not give an appreciable understanding of nuclear fallout, which was not well understood by the project scientists until well after the atomic bombings of Hiroshima and Nagasaki.
Nuclear warfare
With the monopoly over nuclear technology broken, worldwide nuclear proliferation accelerated. The United Kingdom tested its first independent atomic bomb in 1952, followed by France in 1960 and then China in 1964. While much smaller than the arsenals of the United States and the Soviet Union, Western Europe's nuclear reserves were nevertheless a significant factor in strategic planning during the Cold War. A top-secret White Paper, compiled by the Royal Air Force and produced for the British Government in 1959, estimated that British bombers carrying nuclear weapons were capable of destroying key cities and military targets in the Soviet Union, with an estimated 16 million deaths in the Soviet Union (half of whom were estimated to be killed on impact and the rest fatally injured) "before" bomber aircraft from the U.S. Strategic Air Command reached their targets.
Fat Man
"Fat Man" was the codename for the nuclear bomb that was detonated over the Japanese city of Nagasaki by the United States on 9 August 1945. It was the second of the only two nuclear weapons ever used in warfare, the first being Little Boy, and its detonation marked the third nuclear explosion in history. It was built by scientists and engineers at Los Alamos Laboratory using plutonium from the Hanford Site, and it was dropped from the Boeing B-29 Superfortress "Bockscar" piloted by Major Charles Sweeney.
The name Fat Man refers to the early design of the bomb because it had a wide, round shape; it was also known as the Mark III. Fat Man was an implosion-type nuclear weapon with a solid plutonium core. The first of that type to be detonated was the Gadget in the Trinity nuclear test less than a month earlier on 16 July at the Alamogordo Bombing and Gunnery Range in New Mexico. Two more were detonated during the Operation Crossroads nuclear tests at Bikini Atoll in 1946, and some 120 were produced between 1947 and 1949, when it was superseded by the Mark 4 nuclear bomb. The Fat Man was retired in 1950.
Nuclear weapons and the United Kingdom
Churchill, now again prime minister, announced on 17 February 1952 that the first British weapon test would occur before the end of the year. During Operation Hurricane, an atomic bomb was detonated on board the frigate anchored in a lagoon in the Monte Bello Islands in Western Australia on 3 October 1952. Britain thereby became the third country to develop and test nuclear weapons.
This led to the development of the first deployed weapon, the Blue Danube free-fall bomb. It had a diameter, 32 explosive lens implosion system with a levitated pit suspended within a natural uranium tamper. The warhead was contained within a bomb casing measuring diameter and long, and it weighed approximately , of which about was high explosive. The first Blue Danube bombs were delivered to the Royal Air Force (RAF) Bomber Command in November 1953, although the bombers to deliver them did not become available until 1955.
Franklin D. Roosevelt
In August 1939, Leo Szilard and Albert Einstein sent the Einstein–Szilárd letter to Roosevelt, warning of the possibility of a German project to develop nuclear weapons. Szilard realized that the recently discovered process of nuclear fission could be used to create a nuclear chain reaction that could be used as a weapon of mass destruction. Roosevelt feared the consequences of allowing Germany to have sole possession of the technology, and authorized preliminary research into nuclear weapons. After the attack on Pearl Harbor, the Roosevelt administration secured the funds needed to continue research and selected General Leslie Groves to oversee the Manhattan Project, which was charged with developing the first nuclear weapons. Roosevelt and Churchill agreed to jointly pursue the project, and Roosevelt helped ensure that American scientists cooperated with their British counterparts.
History of nuclear weapons
Not to be outdone, the Soviet Union exploded its first thermonuclear device, designed by the physicist Andrei Sakharov, on August 12, 1953, labeled "Joe-4" by the West. This created concern within the U.S. government and military, because, unlike Mike, the Soviet device was a deliverable weapon, which the U.S. did not yet have. This first device though was arguably not a true hydrogen bomb, and could only reach explosive yields in the hundreds of kilotons (never reaching the megaton range of a staged weapon). Still, it was a powerful propaganda tool for the Soviet Union, and the technical differences were fairly oblique to the American public and politicians.
Nuclear weapon
In 1957, the International Atomic Energy Agency (IAEA) was established under the mandate of the United Nations to encourage development of peaceful applications of nuclear technology, provide international safeguards against its misuse, and facilitate the application of safety measures in its use. In 1996, many nations signed the Comprehensive Nuclear-Test-Ban Treaty, which prohibits all testing of nuclear weapons. A testing ban imposes a significant hindrance to nuclear arms development by any complying country. The Treaty requires the ratification by 44 specific states before it can go into force; , the ratification of eight of these states is still required.
Nuclear weapon design
The idea of the hydrogen bomb first came to public attention in 1949, when prominent scientists openly recommended against building nuclear bombs more powerful than the standard pure-fission model, on both moral and practical grounds. Their assumption was that critical mass considerations would limit the potential size of fission explosions, but that a fusion explosion could be as large as its supply of fuel, which has no critical mass limit. In 1949, the Soviets exploded their first fission bomb, and in 1950 U.S. President Harry S. Truman ended the H-bomb debate by ordering the Los Alamos designers to build one.
Treaty on the Prohibition of Nuclear Weapons
The Treaty on the Prohibition of Nuclear Weapons (TPNW), or the Nuclear Weapon Ban Treaty, is the first legally binding international agreement to comprehensively prohibit nuclear weapons, with the goal of leading towards their total elimination. It was passed on 7 July 2017. In order to come into effect, signature and ratification by at least 50 countries is required. For those nations that are party to it, the treaty prohibits the development, testing, production, stockpiling, stationing, transfer, use and threat of use of nuclear weapons, as well as assistance and encouragement to the prohibited activities. For nuclear armed states joining the treaty, it provides for a time-bound framework for negotiations leading to the verified and irreversible elimination of its nuclear weapons programme.
National technical means of verification
France tested its first nuclear weapon on February 13, 1960 in Algeria. This came as no surprise, as multiple US intelligence sources and methods had been following the program since France began considering nuclear weapons in 1946.
Raemer Schreiber
Raemer Edgar Schreiber (November 11, 1910 – December 24, 1998) was an American physicist from McMinnville, Oregon who served Los Alamos National Laboratory during World War II, participating in the development of the atomic bomb. He saw the first one detonated in the Trinity nuclear test in July 1945, and prepared the Fat Man bomb that was used in the bombing of Nagasaki. After the war, he served at Los Alamos as a group leader, and was involved in the design of the hydrogen bomb. In 1955, he became the head of its Nuclear Rocket Propulsion (N) Division, which developed the first nuclear-powered rockets. He served as deputy director of the laboratory from 1972 until his retirement in 1974.
Niels Bohr
In June 1950, Bohr addressed an "Open Letter" to the United Nations calling for international cooperation on nuclear energy. In the 1950s, after the Soviet Union's first nuclear weapon test, the International Atomic Energy Agency was created along the lines of Bohr's suggestion. In 1957 he received the first ever Atoms for Peace Award.
Nuclear artillery
After the abortive effort with purpose-built artillery pieces, the Soviet approach to nuclear artillery was that nuclear munitions should be fired by standard guns and howitzers (without modification), in normal artillery units. The first nuclear weapon for use from standard 152 mm artillery, called ZBV3, was finally accepted in 1965. Subsequent weapon designs followed using existing and new technology:
Massive retaliation
In August 1945, towards the end of the Pacific theater of World War II, the United States delivered nuclear attacks on Hiroshima and Nagasaki in Japan. Four years later, on August 9, 1949, the Soviet Union developed its own nuclear weapons. At the time, both sides lacked the means to effectively use nuclear devices against each other. Eventually with nuclear triads being established, both countries were quickly increasing their ability to deliver nuclear weapons into the interior of the opposing country.
Pakistan and weapons of mass destruction
Pakistan is one of nine states to possess nuclear weapons. Pakistan began development of nuclear weapons in January 1972 under Prime Minister Zulfikar Ali Bhutto, who delegated the program to the Chairman of the Pakistan Atomic Energy Commission (PAEC) Munir Ahmad Khan with a commitment to having the bomb ready by the end of 1976. Since PAEC, consisting of over twenty laboratories and projects under nuclear engineer Munir Ahmad Khan, was falling behind schedule and having considerable difficulty producing fissile material, Abdul Qadeer Khan was brought from Europe by Bhutto at the end of 1974. As pointed out by Houston Wood, Professor of Mechanical & Aerospace Engineering, University of Virginia, Charlottesville, in his article on gas centrifuges, "The most difficult step in building a nuclear weapon is the production of fissile material"; as such, this work in producing fissile material as head of the Kahuta Project was pivotal to Pakistan developing the capability to detonate a nuclear bomb by the end of 1984.
Nuclear weapons debate
After the bombings of Hiroshima and Nagasaki, the world’s nuclear weapons stockpiles grew, and nuclear weapons have been detonated on over two thousand occasions for testing and demonstration purposes. Countries known to have detonated nuclear weapons—and that acknowledge possessing such weapons—are (chronologically): the United States, the Soviet Union (succeeded as a nuclear power by Russia), the United Kingdom, France, the People's Republic of China, India, Pakistan, and North Korea.
Mark 5 nuclear bomb
The Mark 5 nuclear bomb and W5 nuclear warhead were a common core nuclear weapon design, designed in the early 1950s and which saw service from 1952 to 1963.
The Mark 5 design was the first production American nuclear weapon which was significantly smaller than the 60 inch (150 cm) diameter implosion system of the Fat Man nuclear bomb design first used in 1945, down to 39 inches (99.1 cm) diameter. The Mark 5 design used a 92-point implosion system (see Nuclear weapon design) and a composite Uranium/Plutonium fissile material core or pit.
United States v. Progressive, Inc.
The first atomic bombs were developed by the wartime Manhattan Project. This was carried out in secret, lest its discovery induce the Axis powers, particularly Germany, to accelerate their own nuclear projects, or undertake covert operations against the project. The military and scientific leaders of the Manhattan Project anticipated a need to release details of their wartime accomplishments, principally as a form of recognition for the participants who had labored in secrecy. Press releases were prepared in advance of the atomic bombings of Hiroshima and Nagasaki, and an official account, known as the Smyth Report after its author, the physicist Henry DeWolf Smyth, was commissioned in April 1944 to provide a history of the project for public release. The Director of the Manhattan Project, Major General Leslie Groves, his scientific adviser, Richard Tolman, and Smyth agreed that information could be publicly released if it was essential for an understanding of the project, or was already generally known or deducible, or had no significance to the production of atomic bombs. The first copies went on sale on August 12, 1945.
Yulii Khariton
In 1949, he and Kirill Shchelkin reported to the Special Committee on the progress of the first Soviet nuclear weapon, the RDS-1, which was tested on 29 August that year. He was deferential to political superiors but supported the scientists under him in a politic and diplomatic way. Physicist and departmental head Andrei Sakharov referred to him as being "zealous and unsparing of himself." ; he spoke for scientists when they changed their focus a two-stage nuclear device with initial compression from 1954 (the RDS-37) and supported requests not to detonate the RDS-220 (the largest-ever bomb) because of the calculated number of deaths due to radioactive fallout. He would not support similar requests to halt a duplicate test by a second 'Installation' at Snezhinsk which he felt was divisive, and wouldn't intercede in certain politically-charged personal cases.