Portal:Nuclear technology

The Nuclear Technology Portal

Introduction

This symbol of radioactivity is internationally recognized.

• Nuclear technology is technology that involves the nuclear reactions of atomic nuclei. Among the notable nuclear technologies are nuclear reactors, nuclear medicine and nuclear weapons. It is also used, among other things, in smoke detectors and gun sights. (Full article...)
  
• Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced by nuclear fission of uranium and plutonium in nuclear power plants. Nuclear decay processes are used in niche applications such as radioisotope thermoelectric generators in some space probes such as Voyager 2. Generating electricity from fusion power remains the focus of international research. (Full article...)
  
• A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or a combination of fission and fusion reactions (thermonuclear bomb), producing a nuclear explosion. Both bomb types release large quantities of energy from relatively small amounts of matter. (Full article...)

General images -

The following are images from various nuclear technology-related articles on Wikipedia.

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  The USSR and United States nuclear weapon stockpiles throughout the Cold War until 2015, with a precipitous drop in total numbers following the end of the Cold War in 1991. (from Nuclear weapon)
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  Proportions of the isotopes uranium-238 (blue) and uranium-235 (red) found in natural uranium and in enriched uranium for different applications. Light water reactors use 3–5% enriched uranium, while CANDU reactors work with natural uranium. (from Nuclear power)
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  Protest in Bonn against the nuclear arms race between the U.S./NATO and the Warsaw Pact, 1981 (from Nuclear weapon)
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  Death rates from air pollution and accidents related to energy production, measured in deaths in the past per terawatt hours (TWh) (from Nuclear power)
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  The Leibstadt Nuclear Power Plant in Switzerland (from Nuclear power)
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  In thermal nuclear reactors (LWRs in specific), the coolant acts as a moderator that must slow down the neutrons before they can be efficiently absorbed by the fuel. (from Nuclear reactor)
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  Otto Hahn and Lise Meitner in 1912 (from Nuclear fission)
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  Core of CROCUS, a small nuclear reactor used for research at the EPFL in Switzerland (from Nuclear reactor)
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  The Torness nuclear power station – an AGR (from Nuclear reactor)
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  The Trinity test of the Manhattan Project was the first detonation of a nuclear weapon, which led J. Robert Oppenheimer to recall verses from the Hindu scripture Bhagavad Gita: "If the radiance of a thousand suns were to burst at once into the sky, that would be like the splendor of the mighty one "... "I am become Death, the destroyer of worlds". (from Nuclear weapon)
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  Fission product yields by mass for thermal neutron fission of uranium-235, plutonium-239, a combination of the two typical of current nuclear power reactors, and uranium-233, used in the thorium cycle. (from Nuclear fission)
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  Lise Meitner and Otto Hahn in their laboratory (from Nuclear reactor)
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  This view of downtown Las Vegas shows a mushroom cloud in the background. Scenes such as this were typical during the 1950s. From 1951 to 1962 the government conducted 100 atmospheric tests at the nearby Nevada Test Site. (from Nuclear weapon)
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  The first nuclear weapons were gravity bombs, such as this "Fat Man" weapon dropped on Nagasaki, Japan. They were large and could only be delivered by heavy bomber aircraft (from Nuclear weapon)
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  The Ignalina Nuclear Power Plant – a RBMK type (closed 2009) (from Nuclear reactor)
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  Olkiluoto 3 under construction in 2009. It was the first EPR, a modernized PWR design, to start construction. (from Nuclear power)
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  The Calder Hall nuclear power station in the United Kingdom, the world's first commercial nuclear power station. (from Nuclear power)
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  The Chicago Pile, the first artificial nuclear reactor, built in secrecy at the University of Chicago in 1942 during World War II as part of the US's Manhattan project (from Nuclear reactor)
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  The Superphénix, closed in 1998, was one of the few FBRs. (from Nuclear reactor)
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  Typical composition of uranium dioxide fuel before and after approximately three years in the once-through nuclear fuel cycle of a LWR (from Nuclear power)
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  An example of an induced nuclear fission event. A neutron is absorbed by the nucleus of a uranium-235 atom, which in turn splits into fast-moving lighter elements (fission products) and free neutrons. Though both reactors and nuclear weapons rely on nuclear chain reactions, the rate of reactions in a reactor is much slower than in a bomb. (from Nuclear reactor)
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  Growth of worldwide nuclear power generation (from Nuclear power)
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  Three of the reactors at Fukushima I overheated, causing the coolant water to dissociate and led to the hydrogen explosions. This along with fuel meltdowns released large amounts of radioactive material into the air. (from Nuclear reactor)
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  Anti-nuclear weapons protest march in Oxford, 1980 (from Nuclear weapon)
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  The Ikata Nuclear Power Plant, a pressurized water reactor that cools by utilizing a secondary coolant heat exchanger with a large body of water, an alternative cooling approach to large cooling towers (from Nuclear power)
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  The nuclear fission display at the Deutsches Museum in Munich. The table and instruments are originals, but would not have been together in the same room. (from Nuclear fission)
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  Activity of spent UOx fuel in comparison to the activity of natural uranium ore over time (from Nuclear power)
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  Primary coolant system showing reactor pressure vessel (red), steam generators (purple), pressurizer (blue), and pumps (green) in the three coolant loop Hualong One pressurized water reactor design (from Nuclear reactor)
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  Induced fission reaction. A neutron is absorbed by a uranium-235 nucleus, turning it briefly into an excited uranium-236 nucleus, with the excitation energy provided by the kinetic energy of the neutron plus the forces that bind the neutron. The uranium-236, in turn, splits into fast-moving lighter elements (fission products) and releases several free neutrons, one or more "prompt gamma rays" (not shown) and a (proportionally) large amount of kinetic energy. (from Nuclear fission)
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  Soviet OTR-21 Tochka missile. Capable of firing a 100-kiloton nuclear warhead a distance of 185 km (from Nuclear weapon)
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  A photograph of Sumiteru Taniguchi's back injuries taken in January 1946 by a U.S. Marine photographer (from Nuclear weapon)
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  Reactor decay heat as a fraction of full power after the reactor shutdown, using two different correlations. To remove the decay heat, reactors need cooling after the shutdown of the fission reactions. A loss of the ability to remove decay heat caused the Fukushima accident. (from Nuclear power)
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  A schematic nuclear fission chain reaction. 1. A uranium-235 atom absorbs a neutron and fissions into two new atoms (fission fragments), releasing three new neutrons and some binding energy. 2. One of those neutrons is absorbed by an atom of uranium-238 and does not continue the reaction. Another neutron is simply lost and does not collide with anything, also not continuing the reaction. However, the one neutron does collide with an atom of uranium-235, which then fissions and releases two neutrons and some binding energy. 3. Both of those neutrons collide with uranium-235 atoms, each of which fissions and releases between one and three neutrons, which can then continue the reaction. (from Nuclear fission)
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  A Minuteman III ICBM test launch from Vandenberg Air Force Base, United States. MIRVed land-based ICBMs are considered destabilizing because they tend to put a premium on striking first. (from Nuclear weapon)
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  The cooling towers of the Philippsburg Nuclear Power Plant in Germany (from Nuclear fission)
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  UN vote on adoption of the Treaty on the Prohibition of Nuclear Weapons on July 7, 2017
  

    Yes

    No

    Did not vote

  (from Nuclear weapon)
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  Treatment of the interior part of a VVER-1000 reactor frame at Atommash (from Nuclear reactor)
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  United States and USSR/Russian nuclear weapons stockpiles, 1945–2006. The Megatons to Megawatts Program was the main driving force behind the sharp reduction in the quantity of nuclear weapons worldwide since the cold war ended. (from Nuclear power)
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  The "curve of binding energy": A graph of binding energy per nucleon of common isotopes. (from Nuclear fission)
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  Scaled-down model of TOPAZ nuclear reactor (from Nuclear reactor)
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  Dry cask storage vessels storing spent nuclear fuel assemblies (from Nuclear power)
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  Schematic of the ITER tokamak under construction in France (from Nuclear power)
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  The now decommissioned United States' Peacekeeper missile was an ICBM developed to replace the Minuteman missile in the late 1980s. Each missile, like the heavier lift Russian SS-18 Satan, could contain up to ten nuclear warheads (shown in red), each of which could be aimed at a different target. A factor in the development of MIRVs was to make complete missile defense difficult for an enemy country. (from Nuclear weapon)
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  The Magnox Sizewell A nuclear power station (from Nuclear reactor)
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  The launching ceremony of the USS Nautilus January 1954. In 1958 it would become the first vessel to reach the North Pole. (from Nuclear power)
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  A comparison of prices over time for energy from nuclear fission and from other sources. Over the presented time, thousands of wind turbines and similar were built on assembly lines in mass production resulting in an economy of scale. While nuclear remains bespoke, many first of their kind facilities added in the timeframe indicated and none are in serial production. Our World in Data notes that this cost is the global average, while the 2 projects that drove nuclear pricing upwards were in the US. The organization recognises that the median cost of the most exported and produced nuclear energy facility in the 2010s the South Korean APR1400, remained "constant", including in export.
  LCOE is a measure of the average net present cost of electricity generation for a generating plant over its lifetime. As a metric, it remains controversial as the lifespan of units are not independent but manufacturer projections, not a demonstrated longevity. (from Nuclear power)
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  A demilitarized, commercial launch of the Russian Strategic Rocket Forces R-36 ICBM; also known by the NATO reporting name: SS-18 Satan. Upon its first fielding in the late 1960s, the SS-18 remains the single highest throw weight missile delivery system ever built. (from Nuclear weapon)
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  Share of electricity production from nuclear, 2022 (from Nuclear power)
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  The town of Pripyat abandoned since 1986, with the Chernobyl plant and the Chernobyl New Safe Confinement arch in the distance (from Nuclear power)
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  Ukrainian workers use equipment provided by the U.S. Defense Threat Reduction Agency to dismantle a Soviet-era missile silo. After the end of the Cold War, Ukraine and the other non-Russian, post-Soviet republics relinquished Soviet nuclear stockpiles to Russia. (from Nuclear weapon)
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  The multi-mission radioisotope thermoelectric generator (MMRTG), used in several space missions such as the Curiosity Mars rover (from Nuclear power)
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  Most waste packaging, small-scale experimental fuel recycling chemistry and radiopharmaceutical refinement is conducted within remote-handled hot cells. (from Nuclear power)
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  The CANDU Qinshan Nuclear Power Plant (from Nuclear reactor)
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  Anti-nuclear protest near nuclear waste disposal centre at Gorleben in northern Germany (from Nuclear power)
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  The status of nuclear power globally (click for legend) (from Nuclear power)
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  Mushroom cloud from the explosion of Castle Bravo, the largest nuclear weapon detonated by the U.S., in 1954 (from Nuclear weapon)
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  Edward Teller, often referred to as the "father of the hydrogen bomb" (from Nuclear weapon)
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  The mushroom cloud of the atomic bomb dropped on Nagasaki, Japan, on 9 August 1945 rose over 18 kilometres (11 mi) above the bomb's hypocenter. An estimated 39,000 people were killed by the atomic bomb, of whom 23,145–28,113 were Japanese factory workers, 2,000 were Korean slave laborers, and 150 were Japanese combatants. (from Nuclear fission)
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  NC State's PULSTAR Reactor is a 1 MW pool-type research reactor with 4% enriched, pin-type fuel consisting of UO₂ pellets in zircaloy cladding. (from Nuclear reactor)
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  Animation of a Coulomb explosion in the case of a cluster of positively charged nuclei, akin to a cluster of fission fragments. Hue level of color is proportional to (larger) nuclei charge. Electrons (smaller) on this time-scale are seen only stroboscopically and the hue level is their kinetic energy. (from Nuclear fission)
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  J. Robert Oppenheimer, principal leader of the Manhattan Project, often referred to as the "father of the atomic bomb". (from Nuclear weapon)
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  The guided-missile cruiser USS Monterey (CG 61) receives fuel at sea (FAS) from the Nimitz-class aircraft carrier USS George Washington (CVN 73). (from Nuclear power)
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  Over 2,000 nuclear tests have been conducted in over a dozen different sites around the world. Red Russia/Soviet Union, blue France, light blue United States, violet Britain, yellow China, orange India, brown Pakistan, green North Korea and light green (territories exposed to nuclear bombs). The Black dot indicates the location of the Vela incident. (from Nuclear weapon)
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  Following the 2011 Fukushima Daiichi nuclear disaster, the world's worst nuclear accident since 1986, 50,000 households were displaced after radiation leaked into the air, soil and sea. Radiation checks led to bans of some shipments of vegetables and fish. (from Nuclear power)
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  The basics of the Teller–Ulam design for a hydrogen bomb: a fission bomb uses radiation to compress and heat a separate section of fusion fuel. (from Nuclear weapon)
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  The stages of binary fission in a liquid drop model. Energy input deforms the nucleus into a fat "cigar" shape, then a "peanut" shape, followed by binary fission as the two lobes exceed the short-range nuclear force attraction distance, and are then pushed apart and away by their electrical charge. In the liquid drop model, the two fission fragments are predicted to be the same size. The nuclear shell model allows for them to differ in size, as usually experimentally observed. (from Nuclear fission)
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  Some of the Chicago Pile Team, including Enrico Fermi and Leó Szilárd (from Nuclear reactor)
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  The nuclear fuel cycle begins when uranium is mined, enriched, and manufactured into nuclear fuel (1), which is delivered to a nuclear power plant. After use, the spent fuel is delivered to a reprocessing plant (2) or to a final repository (3). In nuclear reprocessing 95% of spent fuel can potentially be recycled to be returned to use in a power plant (4). (from Nuclear power)
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  The number of nuclear warheads by country in 2024, based on an estimation by the Federation of American Scientsts. (from Nuclear weapon)
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  Demonstration against nuclear testing in Lyon, France, in the 1980s. (from Nuclear weapon)
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  Ballistic missile submarines have been of great strategic importance for the United States, Russia, and other nuclear powers since they entered service in the Cold War, as they can hide from reconnaissance satellites and fire their nuclear weapons with virtual impunity. (from Nuclear weapon)
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  Drawing of the first artificial reactor, Chicago Pile-1. (from Nuclear fission)
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  The International Atomic Energy Agency was created in 1957 to encourage peaceful development of nuclear technology while providing international safeguards against nuclear proliferation. (from Nuclear weapon)
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  Montage of an inert test of a United States Trident SLBM (submarine launched ballistic missile), from submerged to the terminal, or re-entry phase, of the multiple independently targetable reentry vehicles (from Nuclear weapon)
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  Life-cycle greenhouse gas emissions of electricity supply technologies, median values calculated by IPCC (from Nuclear power)
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  An assortment of American nuclear intercontinental ballistic missiles at the National Museum of the United States Air Force. Clockwise from top left: PGM-17 Thor, LGM-25C Titan II, HGM-25A Titan I, Thor-Agena, LGM-30G Minuteman III, LGM-118 Peacekeeper, LGM-30A/B/F Minuteman I or II, PGM-19 Jupiter (from Nuclear weapon)
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  Nuclear waste flasks generated by the United States during the Cold War are stored underground at the Waste Isolation Pilot Plant (WIPP) in New Mexico. The facility is seen as a potential demonstration for storing spent fuel from civilian reactors. (from Nuclear power)
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  The first light bulbs ever lit by electricity generated by nuclear power at EBR-1 at Argonne National Laboratory-West, December 20, 1951. (from Nuclear power)
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  Nuclear fuel assemblies being inspected before entering a pressurized water reactor in the United States (from Nuclear power)
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  A visual representation of an induced nuclear fission event where a slow-moving neutron is absorbed by the nucleus of a uranium-235 atom, which fissions into two fast-moving lighter elements (fission products) and additional neutrons. Most of the energy released is in the form of the kinetic velocities of the fission products and the neutrons. (from Nuclear fission)
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  The two basic fission weapon designs (from Nuclear weapon)
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  Diablo Canyon – a PWR (from Nuclear reactor)

Selected article -

Over four weeks in 1954, the United States Atomic Energy Commission (AEC) explored the background, actions, and associations of J. Robert Oppenheimer, the American scientist who directed the Los Alamos Laboratory during World War II as part of the Manhattan Project to develop the atomic bomb. The hearing resulted in Oppenheimer's Q clearance being revoked. This marked the end of his formal relationship with the government of the United States and generated considerable controversy regarding whether the treatment of Oppenheimer was fair, or whether it was an expression of anti-communist McCarthyism.

Doubts about Oppenheimer's loyalty dated back to the 1930s, when he was a member of numerous Communist front organizations and was associated with Communist Party USA members, including his wife, brother and sister-in-law. These associations were known to Army Counterintelligence at the time he was made director of the Los Alamos Laboratory in 1942 and chairman of the influential General Advisory Committee of the AEC in 1947. In this capacity, Oppenheimer became involved in bureaucratic conflict between the Army and Air Force over the types of nuclear weapons the country required, technical conflict between the scientists over the feasibility of the hydrogen bomb, and personal conflict with AEC commissioner Lewis Strauss.

The proceedings were initiated after Oppenheimer refused to voluntarily give up his security clearance while working as an atomic weapons consultant for the government, under a contract due to expire at the end of June 1954. Several of his colleagues testified at the hearings. As a result of the two-to-one decision of the hearing's three judges, he was stripped of his security clearance one day before his consultant contract was due to expire. The panel found that he was loyal and discreet with atomic secrets, but did not recommend that his security clearance be reinstated.

The loss of his security clearance ended Oppenheimer's role in government and policy. He became an academic exile, cut off from his former career and the world he had helped to create. The reputations of those who had testified against Oppenheimer were tarnished as well, though Oppenheimer's reputation was later partly rehabilitated by Presidents John F. Kennedy and Lyndon B. Johnson. The brief period when scientists were viewed as a "public-policy priesthood" ended; thereafter, they would serve the state only to offer narrow scientific opinions. Scientists working in government were on notice that dissent was no longer tolerated.

The fairness of the proceedings has been a subject of controversy, criticized in the acclaimed Oppenheimer biography American Prometheus and dramatized in film and television. On December 16, 2022, United States Secretary of Energy Jennifer Granholm nullified the 1954 decision, saying that it had been the result of a "flawed process" and affirming that Oppenheimer had been loyal. (Full article...)

More selected articles

Selected picture -

Credit: Los Alamos National Laboratory

Krakatau subcritical experiment being lowered into the floor of the tunnel of the U1a Complex at the Nevada Test Site. The cables extending from the hole will carry data from the experiment to recording instruments.

Did you know?

• ... that coral cores from Flinders Reef capture environmental changes caused by the use of nuclear weapons?
• ... that plutonium produced in the nuclear reactors at the Hanford Engineer Works was used in the Fat Man bomb used in the atomic bombing of Nagasaki in August 1945?
• ... that in 1958 the Scyla theta pinch device was the first to demonstrate controlled nuclear fusion in the laboratory?
• ... that Project Carryall proposed the detonation of 23 nuclear devices in California to build a road?
• ... that the sodium fast reactor Fermi 1 suffered a nuclear meltdown that led one operator to suggest "we almost lost Detroit"?
• ... that Project Ketch proposed the detonation of a 24-kiloton nuclear device in Pennsylvania to create a natural-gas storage reservoir?

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Selected biography -

Leslie Richard Groves Jr. (17 August 1896 – 13 July 1970) was a United States Army Corps of Engineers officer who oversaw the construction of the Pentagon and directed the Manhattan Project, a top secret research project that developed the atomic bomb during World War II.

The son of a U.S. Army chaplain, Groves lived at various Army posts during his childhood. In 1918, he graduated fourth in his class at the United States Military Academy at West Point and was commissioned into the United States Army Corps of Engineers. In 1929, he went to Nicaragua as part of an expedition to conduct a survey for the Inter-Oceanic Nicaragua Canal. Following the 1931 Nicaraguan earthquake, Groves took over Managua's water supply system, for which he was awarded the Nicaraguan Presidential Medal of Merit. He attended the Command and General Staff School at Fort Leavenworth, Kansas, in 1935 and 1936, and the Army War College in 1938 and 1939, after which he was posted to the War Department General Staff. Groves developed "a reputation as a doer, a driver, and a stickler for duty". In 1940 he became special assistant for construction to the Quartermaster General, tasked with inspecting construction sites and checking on their progress. In August 1941, he was appointed to create the gigantic office complex for the War Department's 40,000 staff that would ultimately become the Pentagon.

In September 1942, Groves took charge of the Manhattan Project. He was involved in most aspects of the atomic bomb's development: he participated in the selection of sites for research and production at Oak Ridge, Tennessee; Los Alamos, New Mexico; and Hanford, Washington. He directed the enormous construction effort, made critical decisions on the various methods of isotope separation, acquired raw materials, directed the collection of military intelligence on the German nuclear energy project and helped select the cities in Japan that were chosen as targets. Groves wrapped the Manhattan Project in security, but spies working within the project were able to pass some of its most important secrets to the Soviet Union.

After the war, Groves remained in charge of the Manhattan Project until responsibility for nuclear weapons production was handed over to the United States Atomic Energy Commission in 1947. He then headed the Armed Forces Special Weapons Project, which had been created to control the military aspects of nuclear weapons. He was given a dressing down by the Chief of Staff of the Army, General of the Army Dwight D. Eisenhower, on the basis of various complaints, and told that he would never be appointed Chief of Engineers. Three days later, Groves announced his intention to leave the Army. He was promoted to lieutenant general just before his retirement on 29 February 1948 in recognition of his leadership of the bomb program. By a special act of Congress, his date of rank was backdated to 16 July 1945, the date of the Trinity nuclear test. He went on to become a vice president at Sperry Rand. (Full article...)

More selected biographies

Nuclear technology news

14 May 2024 –

Russia places its nuclear capable submarine-launched Bulava intercontinental ballistic missile into service. (Reuters)

9 May 2024 – Joint Comprehensive Plan of Action, Iran–Israel relations

Iran warns that it will build a nuclear weapon if Israel continues to target its nuclear facilities. (Al Jazeera)

25 April 2024 – Russia–NATO relations

Russian Deputy Foreign Minister Sergei Ryabkov warns that Russia will make NATO nuclear weapons in Poland one of its primary targets if they are deployed there. (The Jerusalem Post)

23 April 2024 – North Korea and weapons of mass destruction

North Korea claims that it tested a new command-and-control system in a simulated nuclear counterstrike. (CNN)

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