1.
Fallout Shelter
–
A fallout shelter is an enclosed space specially designed to protect occupants from radioactive debris or fallout resulting from a nuclear explosion. Many such shelters were constructed as civil defense measures during the Cold War, during a nuclear explosion, matter vaporized in the resulting fireball is exposed to neutrons from the explosion, absorbs them, and becomes radioactive. When this material condenses in the rain, it forms dust, the fallout emits alpha and beta particles, as well as gamma rays. Much of this radioactive material falls to earth, subjecting anything within the line of sight to radiation. A fallout shelter is designed to allow its occupants to minimize exposure to harmful fallout until radioactivity has decayed to a safer level, plans were made, however, to use existing buildings with sturdy below-ground-level basements as makeshift fallout shelters. These buildings were usually placarded with the yellow and black trefoil sign, civilian alarm device was engineered and tested but the program was not viable and was terminated in 1967. In the U. S. in September 1961, under the direction of Steuart L. Pittman, a letter from President Kennedy advising the use of fallout shelters appeared in the September 1961 issue of Life magazine. The former Soviet Union and other Eastern Bloc countries often designed their underground mass-transit and subway tunnels to serve as bomb, germany has protected shelters for 3% of its population, Austria for 30%, Finland for 70%, Sweden for 81% and Switzerland for 114%. Later, the law ensured that all buildings built after 1978 contained a nuclear shelter able to withstand a blast from a 12 megaton explosion at a distance of 700 metres. The Federal Law on the Protection of the Population and Civil Protection still requires nowadays that every inhabitant should have a place in a close to where they live. The Swiss authorities also maintain large communal shelters stocked with four months of food. The reference Nuclear War Survival Skills declared that, as of 1986, Switzerland has the best civil defense system, one that already includes blast shelters for over 85 percent of all its citizens. In Switzerland, most residential shelters are no longer stocked with the food and water required for prolonged habitation, but the owner still has the obligation to ensure the maintenance of the shelter. A basic fallout shelter consists of shields that reduce gamma ray exposure by a factor of 1000, the required shielding can be accomplished with 10 times the thickness of any quantity of material capable of cutting gamma ray exposure in half. Shields that reduce gamma ray intensity by 50% include 1 cm of lead,6 cm of concrete,9 cm of packed earth or 150 m of air, when multiple thicknesses are built, the shielding multiplies. Thus, a practical fallout shield is ten halving-thicknesses of packed earth, usually, an expedient purpose-built fallout shelter is a trench, with a strong roof buried by c.1 m of earth. The two ends of the trench have ramps or entrances at right angles to the trench, so that gamma rays cannot enter, to make the overburden waterproof, a plastic sheet may be buried a few inches below the surface and held down with rocks or bricks. Blast doors are designed to absorb the shock wave of a nuclear blast, bending, dry earth is a reasonably good thermal insulator, and over several weeks of habitation, a shelter will become dangerously hot
Fallout Shelter
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A sign pointing to an old fallout shelter in New York City.
Fallout Shelter
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Nuclear weapons
Fallout Shelter
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The
Sonnenberg Tunnel, in
Switzerland, was the world's largest civilian
nuclear fallout shelter, designed to protect 20,000
civilians in the eventuality of war or disaster (
civil defense function abandoned in 2006).
Fallout Shelter
–
Concrete door of a public fallout shelter in Switzerland (2014).
2.
Nuclear weapon
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A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from small amounts of matter. The first test of a bomb released the same amount of energy as approximately 20,000 tons of TNT. The first thermonuclear bomb test released the same amount of energy as approximately 10 million tons of TNT, a thermonuclear weapon weighing little more than 2,400 pounds can produce an explosive force comparable to the detonation of more than 1.2 million tons of TNT. A nuclear device no larger than traditional bombs can devastate a city by blast, fire. Nuclear weapons are considered weapons of destruction, and their use. Nuclear weapons have been used twice in nuclear warfare, both times by the United States against Japan near the end of World War II, the bombings resulted in the deaths of approximately 200,000 civilians and military personnel from acute injuries sustained from the explosions. The ethics of the bombings and their role in Japans surrender remain the subject of scholarly, since the atomic bombings of Hiroshima and Nagasaki, nuclear weapons have been detonated on over two thousand occasions for the purposes of testing and demonstration. Only a few nations possess such weapons or are suspected of seeking them, israel is also believed to possess nuclear weapons, though in a policy of deliberate ambiguity, it does not acknowledge having them. Germany, Italy, Turkey, Belgium and the Netherlands are nuclear weapons sharing states, south Africa is the only country to have independently developed and then renounced and dismantled its nuclear weapons. Modernisation of weapons continues to occur, all existing nuclear weapons derive some of their explosive energy from nuclear fission reactions. Weapons whose explosive output is exclusively from fission reactions are commonly referred to as bombs or atom bombs. This has long noted as something of a misnomer, as their energy comes from the nucleus of the atom. The latter approach is considered more sophisticated than the former and only the approach can be used if the fissile material is plutonium. A major challenge in all nuclear weapon designs is to ensure that a significant fraction of the fuel is consumed before the weapon destroys itself. The amount of energy released by fission bombs can range from the equivalent of just under a ton to upwards of 500,000 tons of TNT, all fission reactions necessarily generate fission products, the radioactive remains of the atomic nuclei split by the fission reactions. Many fission products are highly radioactive or moderately radioactive. Fission products are the radioactive component of nuclear fallout
Nuclear weapon
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The
mushroom cloud of the
atomic bombing of the Japanese city of Nagasaki on August 9, 1945 rose some 11 miles (18 km) above the bomb's
hypocenter.
Nuclear weapon
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Nuclear weapons
Nuclear weapon
–
Edward Teller, often referred to as the "father of the hydrogen bomb"
Nuclear weapon
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A demilitarized and
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.
3.
History of nuclear weapons
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Nuclear weapons possess enormous destructive power from nuclear fission or combined fission and fusion reactions. In August 1945, two bombs were dropped on Japan, and stands to date as the only use of nuclear weapons in combat. The Soviet Union started development shortly thereafter with their own atomic bomb project, in the first decades of the 20th century, physics was revolutionised with developments in the understanding of the nature of atoms. In 1898, Pierre and Marie Curie discovered that pitchblende, an ore of uranium, Ernest Rutherford and Frederick Soddy identified that atoms were breaking down and turning into different elements. Hopes were raised among scientists and laymen that the elements around us could contain tremendous amounts of unseen energy, 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 January 1933, Adolf Hitler was appointed Chancellor of Germany, 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 critical mass to describe the minimum amount of material required to sustain the chain reaction. 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. In December 1938, Otto Hahn and Fritz Strassmann sent a manuscript to Naturwissenschaften reporting that they had detected the element barium after bombarding uranium with neutrons, lise Meitner and her nephew Otto Robert Frisch correctly interpreted these results as being due to the splitting of the uranium atom. They gave the process the name fission because of its similarity to the splitting of a cell into two new cells, even before it was published, news of Meitner’s and Frisch’s interpretation crossed the Atlantic. Scientists at Columbia University decided to replicate the experiment and on January 25,1939, the following year, they identified the active component of uranium as being the rare isotope uranium-235. Uranium appears in nature primarily in two isotopes, uranium-238 and uranium-235, when the nucleus of uranium-235 absorbs a neutron, it undergoes nuclear fission, releasing energy and, on average,2.5 neutrons. Because uranium-235 releases more neutrons than it absorbs, it can support a chain reaction, uranium-238, on the other hand, is not fissile as it does not normally undergo fission when it absorbs a neutron. By the time Nazi Germany invaded Poland in 1939, beginning World War II, 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, Roosevelt responded by setting up the Uranium Committee under Lyman James Briggs but, with little initial funding, progress was slow. It was not until the Japanese attack on Pearl Harbor in December,1941, organized research first began in Britain as part of the Tube Alloys project. The blast from such an explosion would destroy life in a wide area, the size of this area is difficult to estimate, but it will probably cover the centre of a big city. Edgar Sengier, a director of Shinkolobwe Mine in Congo which produced by far the highest quality uranium ore in the world, had become aware of possible use in a bomb
History of nuclear weapons
–
A nuclear fireball lights up the night in the United States nuclear test
Upshot-Knothole Badger on April 18, 1953.
History of nuclear weapons
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Nuclear weapons
History of nuclear weapons
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UC Berkeley physicist
J. Robert Oppenheimer led the Allied scientific effort at
Los Alamos.
History of nuclear weapons
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Electromagnetic U 235 separation plant at Oak Ridge, Tenn. Massive new physics machines were assembled at secret installations around the United States for the production of
enriched uranium and
plutonium.
4.
Nuclear warfare
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Nuclear warfare is a military conflict or political strategy in which nuclear weaponry is used to inflict damage on the enemy. In contrast to conventional warfare, nuclear warfare can produce destruction in a much shorter time-frame, some activists had claimed in the 1980s that with this potential nuclear winter side-effect of a nuclear war, almost every human on Earth could starve to death. 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 was detonated over the Japanese city of Hiroshima. Three days later, on August 9, a plutonium device was detonated over the Japanese city of Nagasaki. These two bombings resulted in the deaths of approximately 120,000 people, in 1974, India, and in 1998, Pakistan, two countries that were openly hostile toward each other, developed nuclear weapons. Israel and North Korea are also thought to have developed stocks of nuclear weapons, the Israeli government has never admitted to having nuclear weapons, although it is known to have constructed the reactor and reprocessing plant necessary for building nuclear weapons. Nuclear weapons have been detonated on over 2,000 occasions for testing purposes, after the collapse of the Soviet Union in 1991 and the resultant end of the Cold War, the threat of a major nuclear war between the two nuclear superpowers was generally thought to have declined. Since then, concern over nuclear weapons has shifted to the prevention of localized nuclear conflicts resulting from nuclear proliferation, the possibility of using nuclear weapons in war is usually divided into two subgroups, each with different effects and potentially fought with different types of nuclear armaments. The first, a nuclear war, refers to a small-scale use of nuclear weapons by two belligerents. This term could apply to any use of nuclear weapons that may involve military or civilian targets. The second, a nuclear war, could consist of large numbers of nuclear weapons used in an attack aimed at an entire country, including military, economic. Such an attack would almost certainly destroy the economic, social, and military infrastructure of the target nation. Some Cold War strategists such as Henry Kissinger argued that a nuclear war could be possible between two heavily armed superpowers. Some predict, however, that a war could potentially escalate into a full-scale nuclear war. Even the most optimistic predictions of the effects of a nuclear exchange foresee the death of many millions of victims within a very short period of time. However, such predictions, assuming total war with nuclear arsenals at Cold War highs, have not been without criticism. The authors of the study estimated that as much as five tons of soot could be released, producing a cooling of several degrees over large areas of North America. The cooling would last for years and could be catastrophic, according to the researchers, either a limited or full-scale nuclear exchange could occur during an accidental nuclear war, in which the use of nuclear weapons is triggered unintentionally
Nuclear warfare
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Nuclear weapons
Nuclear warfare
–
The
Titan II Intercontinental ballistic missile (ICBM) carried a 9
Mt W53 warhead, one of the most powerful
nuclear weapons fielded by the
United States during the
Cold War.
Nuclear warfare
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Mushroom cloud from the atomic explosion over Nagasaki rising 18,000 m (59,000 ft) into the air on the morning of August 9, 1945.
Nuclear warfare
–
Convair B-36 bomber
5.
Nuclear weapon design
–
Nuclear weapon designs are physical, chemical, and engineering arrangements that cause the physics package of a nuclear weapon to detonate. There are three existing basic design types, in many existing designs, the explosive energy of deployed devices is derived primarily from nuclear fission, not fusion. Pure fission weapons were the first nuclear weapons built and have so far been the type ever used in warfare. Implosion, a mass of either material is surrounded by high explosives that compress the mass. The implosion method can use either uranium or plutonium as fuel, the gun method only uses uranium. Boosted fission weapons improve on the implosion design, the high pressure and temperature environment at the center of an exploding fission weapon compresses and heats a mixture of tritium and deuterium gas. The hydrogen fuses to form helium and free neutrons, boosting can more than double the weapons fission energy release. Staged thermonuclear weapons are essentially a chain of fusion-boosted fission weapons, the secondary stage is imploded by x-ray energy from the first stage, called the primary. This radiation implosion is much more effective than the high-explosive implosion of the primary, consequently, the secondary can be many times more powerful than the primary, without being bigger. The secondary can be designed to maximize fusion energy release, but in most designs fusion is employed only to drive or enhance fission, as it is in the primary. More stages could be added and conceptual designs incorporating up to seven have been produced, pure fusion weapons have not been invented. Such weapons, though, would produce far less radioactive fallout than current designs, pure fission weapons historically have been the first type to be built by a nation state. Most known innovations in nuclear weapon design originated in the United States, although some were developed independently by other states. In early news accounts, pure fission weapons were called atomic bombs or A-bombs, Weapons involving fusion were called hydrogen bombs or H-bombs, also a misnomer since their energy comes mostly from fission. Practitioners favored the terms nuclear and thermonuclear, respectively, the term thermonuclear refers to the high temperatures required to initiate fusion. It omits the equally important factor of radiation pressure, which was considered secret at the time the term became widespread, many nuclear weapon terms similarly obfuscate because of their origin in a classified environment. Nuclear fission separates or splits heavier atoms to form lighter atoms, Nuclear fusion combines together lighter atoms to form heavier atoms. In some ways, fission and fusion are opposite and complementary reactions, to understand how nuclear weapons are designed, it is useful to know the important similarities and differences between fission and fusion
Nuclear weapon design
–
The first nuclear weapons, cumbersome and inefficient, provided the basic design building blocks of all future weapons. Here the
Gadget device is prepared for the first
nuclear test:
Trinity.
Nuclear weapon design
–
Nuclear weapons
Nuclear weapon design
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Ivy Mike, the first two-stage thermonuclear detonation, 10.4 megatons, November 1, 1952.
Nuclear weapon design
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Bassoon, the prototype for a 9.3-megaton clean bomb or a 25-megaton dirty bomb. Dirty version shown here, before its 1956 test. The two attachments on the left are light pipes - see below for elaboration.
6.
Nuclear weapons testing
–
Nuclear weapons tests are experiments carried out to determine the effectiveness, yield, and explosive capability of nuclear weapons. Throughout the twentieth century, most nations that developed nuclear weapons tested them, 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 Mike, was tested at the Enewetak atoll in the Marshall Islands on November 1,1952, 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, the treaty permitted underground nuclear testing. France continued atmospheric testing until 1974, and China continued until 1980, underground tests in the United States continued until 1991, the Soviet Union until 1990, the United Kingdom until 1991, and both China and France until 1996. Non-signatories India and Pakistan last tested nuclear weapons in 1998, North Korea conducted nuclear tests in 2006,2009,2013, and 2016. The most recent confirmed nuclear test occurred in September 2016 in North Korea, Nuclear weapons tests have historically been divided into four categories reflecting the medium or location of the test. Atmospheric testing designates explosions that take place in the atmosphere, Nuclear explosions close enough to the ground to draw dirt and debris into their mushroom cloud can generate large amounts of nuclear fallout due to irradiation of the debris. This definition of atmospheric is used in the Limited Test Ban Treaty, underground testing refers to nuclear tests conducted under the surface of the earth, at varying depths. True underground tests are intended to be contained and emit a negligible amount of fallout. Unfortunately these nuclear tests do occasionally vent to the surface, producing from nearly none to considerable amounts of debris as a consequence. In 1976, the United States and the USSR agreed to limit the maximum yield of underground tests to 150 kt with the Threshold Test Ban Treaty. Underground testing also falls into two categories, tunnel tests in generally horizontal tunnel drifts, and shaft tests in vertically drilled holes. Exoatmospheric testing refers to tests conducted above the atmosphere. The test devices are lifted on rockets, underwater testing results from nuclear devices being detonated underwater, usually moored to a ship or a barge. Tests of this nature have usually been conducted to evaluate the effects of weapons against naval vessels. Another way to nuclear tests are by the number of explosions that constitute the test.1 second. The USSR has exploded up to eight devices in a single salvo test, Pakistans second, almost all lists in the literature are lists of tests, in the lists in Wikipedia, the lists are of explosions
Nuclear weapons testing
–
Nuclear weapons
Nuclear weapons testing
–
Sub-critical experiment at the
Nevada Test Site.
Nuclear weapons testing
–
The
Phoenix of Hiroshima (foreground) in Hong Kong Harbor in 1967, was involved in several famous
anti-nuclear protest voyages against nuclear testing in the Pacific.
Nuclear weapons testing
–
The first atomic test, "
Trinity ", took place on July 16, 1945.
7.
Nuclear weapons delivery
–
Nuclear weapons delivery is the technology and systems used to place a nuclear weapon at the position of detonation, on or near its target. Several methods have developed to carry out this task. Strategic nuclear weapons are used primarily as part of a doctrine of deterrence by threatening large targets, weapons meant for use in limited military maneuvers, such as destroying specific military, communications, or infrastructure targets, are known as tactical nuclear weapons. In terms of yields, nowadays the former have much larger yield than the latter. The bombs that destroyed Hiroshima and Nagasaki in 1945 were weaker than many of todays tactical weapons, historically, the first method of delivery, and the method used in the only two nuclear weapons actually used in warfare, was a gravity bomb dropped by a plane. S. Nuclear warheads are represented in bombs, although some are in the form of missiles, gravity bombs are designed to be dropped from planes, which requires that the weapon be able to withstand vibrations and changes in air temperature and pressure during the course of a flight. Early weapons often had a core for safety, known as in flight insertion cores. They had to meet safety conditions, to prevent accidental detonation or dropping, a variety of types also had to have a fuse to initiate detonation. US nuclear weapons that met these criteria are designated by the letter B followed, without a hyphen, the B61, for example, was the primary bomb in the US arsenal for decades. Various air-dropping techniques exist, including bombing, parachute-retarded delivery. The early gravity nuclear bombs could only be carried by the B-29 Superfortress, most ballistic missiles exit the Earths atmosphere and re-enter it in their sub-orbital spaceflight. Placement of nuclear missiles on the low Earth orbit has been banned by the Outer Space Treaty as early as 1967. An ICBM is more than 20 times as fast as a bomber and more than 10 times as fast as a plane, and also flying at a much higher altitude. ICBMs can also be fired quickly in the event of a surprise attack, early ballistic missiles carried a single warhead, often of megaton-range yield. Because of the accuracy of the missiles, this kind of high yield was considered necessary in order to ensure a particular targets destruction. Since the 1970s modern ballistic weapons have seen the development of far more accurate targeting technologies and this set the stage for smaller warheads in the hundreds-of-kilotons-range yield, and consequently for ICBMs having multiple independently targetable reentry vehicles. Advances in technology have enabled a single missile to launch a payload containing several warheads, the number of independent warheads capable of deployment from ballistic missiles depends on the weapons platform the missile is launched from. For example, one D5 Trident missile carried by an Ohio-class submarine is capable of launching eight independent warheads, MIRV has a number of advantages over a missile with a single warhead
Nuclear weapons delivery
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Nuclear weapons
Nuclear weapons delivery
–
Trident II SLBM launched by
Royal Navy Vanguard class submarine.
Nuclear weapons delivery
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Cruise missiles have a shorter range than
ICBMs.
U/RGM-109E Tomahawk pictured (not nuclear capable anymore).
Nuclear weapons delivery
–
The
Davy Crockett artillery shell is the smallest known nuclear weapon developed by the USA.
8.
Nuclear weapon yield
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An explosive yield of one terajoule is 0.239 kt of TNT. The yield-to-weight ratio is the amount of weapon yield compared to the mass of the weapon, the practical maximum yield-to-weight ratio for fusion weapons has been estimated to six megatons of TNT per metric ton of bomb mass. Yields of 5.2 megatons/ton and higher have been reported for large weapons constructed for use in the early 1960s. Most artificial non-nuclear explosions are considerably smaller than even what are considered to be very small nuclear weapons, the yield-to-weight ratio is the amount of weapon yield compared to the mass of the weapon. According to nuclear-weapons designer Ted Taylor, the practical maximum yield-to-weight ratio for fusion weapons is about 6 megatons of TNT per metric ton. The Taylor limit is not derived from first principles, and weapons with yields as high as 9.5 megatons per metric ton have been designed and built. The 25 Mt yield option reported for the B41 would give it a ratio of 5.1 megatons of TNT per metric ton. This results in the B41 still retaining the record for the highest Yield-to-weight weapon ever designed, in 1963 DOE declassified statements that the U. S. had the technological capability of deploying a 35 Mt warhead on the Titan II, or a 50-60 Mt gravity bomb on B-52s. Neither weapon was pursued, but either would require yield-to-weight ratios superior to a 25 Mt Mk-41, for current smaller US weapons, yield is 600 to 2200 kilotons of TNT per metric ton. By comparison, for the very small devices such as the Davy Crockett it was 0.4 to 40 kilotons of TNT per metric ton. For historical comparison, for Little Boy the yield was only 4 kilotons of TNT per metric ton, and for the largest Tsar Bomba, the yield was 2 megatons of TNT per metric ton. The largest pure-fission bomb ever constructed Ivy King had a 500 kiloton yield, however, there is no known upper yield limit for a fusion bomb. For example, the Mk-36 bomb as built had a ratio of 1.25 megatons of TNT per metric ton. Delivery size limits can be estimated to ascertain limits to delivery of high yield weapons. If the full 250 metric ton payload of the Antonov An-225 aircraft could be used, likewise, the maximum limit of a missile-delivered weapon is determined by the missile gross payload capacity. The large Russian SS-18 ICBM has a capacity of 7,200 kg. A Saturn V-scale missile could deliver over 120 tons, giving a maximum yield of about 700 megatons. The following list is of nuclear explosions
Nuclear weapon yield
–
Picture of the blast, captured by
Berlyn Brixner were used by G.I. Taylor to estimate the yield of the device during the
Trinity test
Nuclear weapon yield
–
Logarithmic scatterplot comparing the yield (in kilotons) and weight (in kilograms) of various nuclear weapons developed by the United States.
9.
Effects of nuclear explosions
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The blast effect is created by the coupling of immense amounts of energy, spanning the electromagnetic spectrum, with the surroundings. Locations such as submarine, surface, air burst, or exo-atmospheric determine how energy is produced as blast. In general, denser media around the bomb, like water, absorb more energy, when an air burst occurs, lethal blast and thermal effects proportionally scale much more rapidly than lethal radiation effects, as higher and higher yield nuclear weapons are used. Energy from an explosive is initially released in several forms of penetrating radiation. When there is a material such as air, rock, or water. This causes vaporization of surrounding material resulting in its rapid expansion, kinetic energy created by this expansion contributes to the formation of a shockwave. When a nuclear detonation occurs in air near sea level, much of the released energy interacts with the atmosphere, intense thermal radiation at the hypocenter forms a nuclear fireball and if the burst is low enough, it is often associated with a mushroom cloud. In a burst at high altitude, where the air density is low, more energy is released as ionizing gamma radiation and this would concern a nuclear reaction of two nitrogen atoms forming a carbon and an oxygen atom, with release of energy. This energy would heat up the remaining nitrogen enough to keep the reaction going until all nitrogen atoms were consumed. Hans Bethe was assigned the task of studying there was a possibility in the very early days. Richard Hamming, a mathematician, was asked to make a similar calculation just before Trinity, nevertheless, the notion has persisted as a rumor for many years, and was the source of black humor at the Trinity test. The high temperatures and radiation cause gas to move outward radially in a thin, the front acts like a piston that pushes against and compresses the surrounding medium to make a spherically expanding shock wave. At first, this wave is inside the surface of the developing fireball. For air bursts at or near sea-level, 50–60% of the energy goes into the blast wave, depending on the size. As a general rule, the blast fraction is higher for low yield weapons, furthermore, it decreases at high altitudes because there is less air mass to absorb radiation energy and convert it into blast. This effect is most important for altitudes above 30 km, corresponding to <1 per cent of air density. The effects of a rain storm during an Operation Castle nuclear explosion was found to dampen, or reduce. Much of the caused by a nuclear explosion is due to blast effects
Effects of nuclear explosions
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Nuclear weapons
Effects of nuclear explosions
Effects of nuclear explosions
–
Burns visible on a woman in Hiroshima during the blast. Darker colors of her
kimono at the time of detonation correspond to clearly visible burns on the skin which touched parts of the garment exposed to thermal radiation. Since kimonos are not form-fitting attire, some parts not directly touching her skin are visible as breaks in the pattern, and the tighter-fitting areas approaching the waistline have a much more well-defined pattern.
10.
Nuclear explosion
–
A nuclear explosion is an explosion that occurs as a result of the rapid release of energy from a high-speed nuclear reaction. Atmospheric nuclear explosions are associated with clouds, although mushroom clouds can occur with large chemical explosions. It is possible to have an air-burst nuclear explosion without these clouds, nuclear explosions produce radiation and radioactive debris. Any nuclear explosion would have wide-ranging, long-term, catastrophic effects, radioactive contamination would cause genetic mutations and cancer across many generations. The first nuclear explosion occurred on July 16,1945 at 5,50 am on the Trinity Test Site near Alamogordo, New Mexico in the United States, the event involved the full-scale testing of an implosion-type fission atomic bomb. In a memorandum to the U. S. Secretary of War, in the years following World War II, eight countries have conducted nuclear tests with 2475 devices fired in 2120 tests. In 1963, the United States, Soviet Union, and United Kingdom signed the Limited Test Ban Treaty, pledging to refrain from testing nuclear weapons in the atmosphere, underwater, or in outer space. Many other non-nuclear nations acceded to the Treaty following its entry into force, however, power generation, see PACER Peaceful nuclear explosions Only two nuclear weapons have been deployed in combat—both by the United States against Japan in World War II. The second event occurred three days later when the United States Army Air Forces dropped a plutonium device, code-named Fat Man. It killed 39,000 people, including 27,778 Japanese munitions employees,2,000 Korean slave laborers, in total, around 119,000 people were killed in these bombings. Since the Trinity test and excluding the use of nuclear weapons, mankind has detonated roughly 1,700 nuclear explosions. 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. The devastating impact of the explosion does not stop after the initial blast, a cloud of nuclear radiation travels from the epicenter of the explosion, causing an impact to life forms even after the heat waves have ceased. Any nuclear explosion would have wide-ranging, long-term, catastrophic effects, radioactive contamination would cause genetic mutations and cancer across many generations. Lists of nuclear disasters and radioactive incidents Soviet nuclear well collapses Visual depictions of explosions in fiction
Nuclear explosion
–
Nuclear weapons
11.
Nuclear winter
–
Nuclear winter is the severe global-climatic-cooling-effect, hypothesized to occur after the ignition of a number of firestorms. It was within this early 1980s context, that the effects of soot from fires, was chanced upon. In these modelled scenarios, various soot cloud events, containing quantities of soot, were assumed to form over cities, oil refineries. Once the quantity of soot is decided upon by the researchers, the term nuclear winter was specifically coined in 1983 by Richard P. As nuclear devices need not be involved in the ignition of a firestorm and this is due, in greatest part, to the vast majority of published papers stating, without qualitative justification, that nuclear explosions are the cause of the modeled firestorm effects. Although rarely discussed, the proponents of the hypothesis do state that the nuclear winter effect would occur if 100 conventionally lit firestorms were ignited. The climate models suggest that the ignition of 100 firestorms, comparable in intensity to that observed in Hiroshima in 1945, the burning of these firestorms would result in the injection of soot into the Earths stratosphere, producing an anti-greenhouse effect that lowers the Earths surface temperature. Robock has not modeled, but speculated, that this would have global agricultural losses as a consequence, a much larger number of firestorms, in the thousands, was the initial assumption of the computer modelers who coined the term in the 1980s. These were speculated to be a result of any large scale employment of countervalue city-airbursting nuclear weapon use during an American-Soviet total war. This cooling was produced due to a 99% reduction in the solar radiation reaching the surface of the planet in the first few years. This is somewhat analogous to the frequent volcanic eruptions that inject sulfates into the stratosphere and thereby produce minor, even negligible, volcanic winter effects. Information regarding all of these properties is necessary to ascertain the length and depth of the cooling effect of firestorms. Presently, from satellite tracking data, stratospheric smoke aerosols are removed in a time span under approximately two months, the existence of any hint of a tipping point into a new stratospheric condition where the aerosols would not be removed within this time frame remains to be determined. As the incendiary effects of a nuclear explosion do not present any especially characteristic features.2 kilotons of incendiary bombs from 220 B-29s distributed over the city, aerosol–atmosphere interactions are still poorly understood. Sooty aerosols can have a range of properties, as well as complex shapes. These partially burnt organics as they are known, often form tar balls and brown carbon during common lower-intensity wildfires, and can also coat the purer carbon black particles. A study presented at the meeting of the American Geophysical Union in December 2006 found that even a small-scale. The cooling would last for years, and, according to the research, a 2008 study by Michael J
Nuclear winter
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Nuclear weapons
Nuclear winter
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Picture of a
pyrocumulonimbus cloud taken from a commercial airliner cruising at about 10 km. In 2002 various sensing instruments detected 17 distinct pyrocumulonimbus cloud events in North America alone.
Nuclear winter
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Smoke rising in
Lochcarron,
Scotland, is stopped by an overlying natural low-level
inversion layer of warmer air (2006).
Nuclear winter
12.
Nuclear labor issues
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A subculture of frequently undocumented workers do the dirty, difficult, and potentially dangerous work shunned by regular employees. When they exceed their allowable radiation exposure limit at a specific facility, the industry implicitly accepts this conduct as it can not operate without these practices. The World Nuclear Association states that the transient workforce of nuclear gypsies - casual workers employed by subcontractors has been part of the scene for at least four decades. Existent labor laws protecting worker’s health rights are not always properly enforced, records are required to be kept, but frequently they are not. Some personnel were not properly trained resulting in their own exposure to toxic amounts of radiation, at several facilities there are ongoing failures to perform required radiological screenings or to implement corrective actions. The median annual wage for hazardous radioactive materials removal workers, according to the U. S. Bureau of Labor Statistics is $37,590 in the U. S - $18 per hour. A 15-country collaborative cohort study of cancer due to exposure to low-dose ionizing radiation. The study evaluated 31 types of cancers, primary and secondary, in 1942 thirty indigenous Dené men were recruited to mine uranium, locally known as the money rock for three dollars per day at the Port Radium mine. By 1998,14 of these workers had died of lung, colon and kidney cancers, the Dené were not told of the hazards of mining uranium, and breathed radioactive dust, slept on the ore, and ate fish from the tailings ponds. Ottawa was the worlds largest supplier of uranium at that time, in subsequent decades, thousands of Native miners were not warned of the risks. Namibias Rössing Uranium Mine is the longest-operating open-pit uranium mine, the company is owned and operated by Rio Tinto, one of the worlds largest mining groups, and Rössing Uranium Limited. The uranium mill tailings dam has been leaking for a number of years, and on January 17,2014, the France-based laboratory, Commission de Recherche et dInformation Independentantes sur la Radioactivite reported elevated levels of radioactive materials in the area surrounding the mine. There have been numerous reports published on labor and human rights conditions at the mine, Workers were not informed of the dangers of working with radioactive materials and the health effects thereof. The Director of Labor Resource and Research Institute, Hilma Shindondola-Mote, at the open cut Kayelekera uranium mine near Karonga, Malawi, a mine employee, Khwima Phiri, was killed on July 20,2013. He was struck in the chest and killed while inflating a wheel, there have been allegations of radiation-induced diseases among the mine workers and nearby residents. The Malawi government has been unable to verify these, stating that the absence of monitoring equipment, on June 19,2011 a truck at the mine caught fire, killing the driver. On September 23,2010, workers were ordered to work despite the fact that the mine could not provide them with dust masks to protect them against radioactive materials. The American and British demand for large quantities of uranium to use in nuclear weapons initiated New Zealands uranium survey during WWII, in 1944 in Wellington, geologists and physicists assembled two exploration teams to survey South Island, particularly the granite deposits and black beach sand areas
Nuclear labor issues
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VOA Herman - April 13, 2011 Fukushima Nuclear Power Plant-04
Nuclear labor issues
–
USRadiumGirls-Argonne
Nuclear labor issues
–
Fuel pool
Nuclear labor issues
–
Arandis Mine hochformat
13.
Nuclear ethics
–
In contemporary security studies, the problems of nuclear warfare, deterrence, proliferation, and so forth are often understood strictly in political, strategic, or military terms. In the study of organizations and law, however, these problems are also understood in legal terms. Specifically, it assumes that the outcomes of human extinction, mass human destruction, another area of inquiry concerns future generations and the burden that nuclear waste and pollution imposes on them. Some scholars have concluded that it is morally wrong to act in ways that produce these outcomes. Ethical justifications of nuclear deterrence, for example, emphasize its role in preventing great power nuclear war since the end of World War II, indeed, some scholars claim that nuclear deterrence seems to be the morally rational response to a nuclear-armed world. Moral condemnation of nuclear deterrence, in contrast, emphasizes the seemingly inevitable violations of human, the application of nuclear technology, both as a source of energy and as an instrument of war, has been controversial. Even before the first nuclear weapons had 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 Japans 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 continually and nearly universally controversial. The public became concerned about nuclear testing from about 1954. In 1961, at the height of the Cold War, about 50,000 women brought together by Women Strike for Peace marched in 60 cities in the United States to demonstrate against nuclear weapons. In 1963, many countries ratified the Partial Test Ban Treaty which prohibited atmospheric nuclear testing, some local opposition to nuclear power emerged in the early 1960s, and in the late 1960s some members of the scientific community began to express their concerns. In the early 1970s, there were protests about a proposed nuclear power plant in Wyhl. The project was cancelled in 1975 and anti-nuclear success at Wyhl inspired opposition to power in other parts of Europe. Nuclear power became an issue of public protest in the 1970s. Between 1949 and 1989, over 4,000 uranium mines in the Four Corner region of the American Southwest produced more than 225,000,000 tons of uranium ore. This activity affected a number of Native American nations, including the Laguna, Navajo, Zuni, Southern Ute, Ute Mountain, Hopi, Acoma. Many of these worked in the mines, mills and processing plants in New Mexico, Arizona, Utah
Nuclear ethics
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Nuclear weapons
Nuclear ethics
–
Trinity shot color
Nuclear ethics
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United Nuclear Corporation Church Rock Uranium Mill
Nuclear ethics
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Moab uranium mill tailings pile
14.
List of nuclear weapons
–
This is a list of nuclear weapons listed according to country of origin, and then by type within the states. US nuclear weapons of all types – bombs, warheads, shells, all designs which were formally intended to be weapons at some point received a number designation. Pure test units which were experiments are not numbered in this sequence, early weapons were very large and could only be used as free fall bombs. These were known by Mark designators, like the Mark 4 which was a development of the Fat Man weapon, as weapons became more sophisticated they also became much smaller and lighter, allowing them to be used in many roles. At this time the weapons began to receive designations based on their role, bombs were given the prefix B, while the same used in other roles, like missiles. For instance, the W-53 warhead was used as the basis for the B53 nuclear bomb. Such examples share the same sequence number, in other cases, when the modifications are more significant, variants are assigned their own number. An example is the B61 nuclear bomb, which was the parent design for the W80, W81, there are also examples of out-of-sequence numbering and other prefixes used in special occasions. This list includes weapons which were developed to the point of being assigned a model number and those models are listed as canceled, along with the year or date of cancellation of their program. Bombs – designated with Mark numbers until 1968, and with B numbers after that, test Experimental bombs designated with TX. Mark 1 – Little Boy gun-type uranium weapon, Mark 3 – Fat Man plutonium implosion weapon. Mark 4 – Post-war Fat Man redesign, Bomb designed with weapon characteristics as the foremost criteria. Mark 5 – Significantly smaller high efficiency nuclear bomb, Mark 6 – Improved version of Mk-4. Mark 7 – Multi-purpose tactical bomb, Mark 8 – Gun-assembly, HEU weapon designed for penetrating hardened targets. Mark 10 – Improved version of Mk-8, Mark 12 – Light-weight bomb to be carried by fighter aircraft. Mark 13 – Improved version of Mk-6, tX/Mark 14 – First deployable solid-fuel thermonuclear bomb. Mark 15 – First lightweight thermonuclear weapon, tX/Mark 16 – First weaponized thermonuclear weapon. Heaviest U. S. weapon, second highest yield of any U. S. weapon, Mark 18 – Very high yield fission weapon
List of nuclear weapons
–
Nuclear weapons
List of nuclear weapons
–
1962 test of an
ASROC antisubmarine rocket armed with the
W44
15.
Nuclear arms race
–
The nuclear arms race was a competition for supremacy in nuclear warfare between the United States, the Soviet Union, and their respective allies during the Cold War. The first nuclear weapon was created by the U. S. 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. When President Truman informed Stalin of the weapons, he was surprised at how calmly Stalin reacted to the news, other members of the United States and British delegations who closely observed the exchange formed the same conclusion. A ring of spies operating within the Manhattan Project, had kept Stalin well informed of American progress and they provided the Soviets with detailed designs of the implosion bomb and the hydrogen bomb. Fuchs arrest in 1950 led to the arrests of many other Russian spies, including Harry Gold, David Greenglass, in August 1945, on Trumans orders, two atomic bombs were dropped on Japanese cities. The first bomb was dropped on Hiroshima, and the bomb was dropped on Nagasaki by the B-29 bombers named Enola Gay. Shortly after the end of the Second World War in 1945, during the United Nations first General Assembly in London in January 1946, they discussed the future of Nuclear Weapons and created the United Nations Atomic Energy Commission. The goal of this assembly was to eliminate the use of all Nuclear weapons, the United States presented their solution, which was called the Baruch Plan. This plan proposed that there should be an authority that controls all dangerous atomic activities. The Soviet Union disagreed with this proposal and rejected it, the Soviets proposal involved universal nuclear disarmament. Both the American and Soviet proposals were refused by the UN, in the years immediately after the Second World War, the United States had a monopoly on specific knowledge of and raw materials for nuclear weaponry. Initially, it was thought that uranium was rare in the world, American leaders hoped that their exclusive ownership of nuclear weapons would be enough to draw concessions from the Soviet Union but this proved ineffective. Just six months after the UN General Assembly, the United States conducted its first post-war nuclear tests, the purpose of this operation was to test the effectiveness of nuclear explosions on ships. These tests were performed at Bikini Atoll in the Pacific on 95 ships, including German, one plutonium implosion-type bomb was detonated over the fleet, while the other one was detonated underwater. 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 weapons until the mid-1950s. The bomb, named First Lightning by the West, was more or less a copy of Fat Man, both governments spent massive amounts to increase the quality and quantity of their nuclear arsenals. Both nations quickly began the development of a bomb and the United States detonated the first hydrogen bomb on November 1,1952, on Enewetak
Nuclear arms race
–
Nuclear weapons
Nuclear arms race
–
United States and
Soviet Union /
Russia nuclear stockpiles
Nuclear arms race
–
A chart of the
Space Race as driven by the nuclear threat, graphing how the U.S. started behind, but eventually caught up and surpassed the Soviet Union.
16.
Nuclear espionage
–
Nuclear espionage is the purposeful giving of state secrets regarding nuclear weapons to other states without authorization. During the history of nuclear weapons there have been cases of known nuclear espionage. States are also limited in their making public of weapons information by non-proliferation agreements and these people are often referred to as the Atomic Spies, and their work continued into the early Cold War. The most prominent of these included, Klaus Fuchs – German refugee theoretical physicist who worked with the British delegation at Los Alamos during the Manhattan Project and he was eventually discovered, confessed, and sentenced to jail in Britain. He was later released, and he emigrated to East Germany, theodore Hall – a young American physicist at Los Alamos, whose identity as a spy was not revealed until very late in the 20th century. He was never arrested in connection to his work, though seems to have admitted to it in later years to reporters. David Greenglass – an American machinist at Los Alamos during the Manhattan Project, Greenglass confessed that he gave crude schematics of lab experiments to the Russians during World War II. Some aspects of his testimony against his sister and brother-in-law are now thought to have been fabricated in an effort to keep his own wife from prosecution, Greenglass confessed to his espionage and was given a long prison term. George Koval – The American born son of a Belorussian emigrant family that returned to the Soviet Union where he was inducted into the Red Army and he infiltrated the US Army and became a radiation health officer in the Special Engineering Detachment. Acting under the code name DELMAR he obtained information from Oak Ridge and his work was not known to the west until he was posthumously recognized as a hero of the Russian Federation by Vladimir Putin in 2007. Ethel and Julius Rosenberg – Americans who were involved in coordinating and recruiting an episonage network which included David Greenglass. While most scholars believe that Julius was likely involved in some sort of network, Julius and Ethel refused to confess to any charges, and were convicted and executed at Sing-Sing Prison. Harry Gold – American, confessed to acting as a courier for Greenglass, whether the espionage information significantly aided the speed of the Soviet atomic bomb project is also disputed. On 10 July 1985, the branch of the French foreign intelligence services carried out the sinking of the Rainbow Warrior. During the operation, two operatives sank the flagship of the Greenpeace fleet, the Rainbow Warrior in the port of Auckland, the French government wanted to prevent the ship from interfering with a planned nuclear test in Moruroa. In April 2013, the French interior intelligence agency DCRI attempted to have the article about the Pierre-sur-Haute military radio station removed from the French language Wikipedia, the DCRI pressured a volunteer administrator of the French language Wikipedia into deleting the article. Israel has never acknowledged or denied having a program, and Vanunu was abducted and smuggled to Israel. Vanunu did not immediately release his information and photos on leaving Israel, the politics of the case are hotly disputed
Nuclear espionage
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Nuclear weapons
17.
Nuclear proliferation
–
Four countries besides the five recognized Nuclear Weapons States have acquired, or are presumed to have acquired, nuclear weapons, India, Pakistan, North Korea, and Israel. None of these four is a party to the NPT, although North Korea acceded to the NPT in 1985, then withdrew in 2003, Research into the development of nuclear weapons was undertaken during World War II by the United States, Germany, Japan, and the USSR. The United States was the first and is the country to have used a nuclear weapon in war. With their loss during the war, Germany and Japan ceased to be involved in any nuclear weapon research, in August 1949, the USSR tested a nuclear weapon. The United Kingdom tested a nuclear weapon in October 1952, France developed a nuclear weapon in 1960. The Peoples Republic of China detonated a weapon in 1964. India exploded a device in 1974, and Pakistan conducted a series of nuclear weapon tests in May 1998. In 2006, North Korea conducted its first nuclear test, none of these efforts were explicitly public, because the weapon developments themselves were kept secret until the bombing of Hiroshima. The Baruch Plan, which drew heavily from the Acheson–Lilienthal Report of 1946, proposed the verifiable dismantlement, Security Council could veto, and which would proportionately punish states attempting to acquire the capability to make nuclear weapons or fissile material. Baruchs plea for the destruction of nuclear weapons invoked basic moral, in one part of his address to the UN, Baruch said, Behind the black portent of the new atomic age lies a hope which, seized upon with faith, can work out our salvation. If we fail, then we have damned every man to be the slave of Fear and we must elect World Peace or World Destruction. We must answer the worlds longing for peace and security, with this remark, Baruch helped launch the field of nuclear ethics, to which many policy experts and scholars have contributed. Although the Baruch Plan enjoyed wide support, it failed to emerge from the UNAEC because the Soviet Union planned to veto it in the Security Council. Still, it remained official American policy until 1953, when President Eisenhower made his Atoms for Peace proposal before the U. N. General Assembly, eisenhowers proposal led eventually to the creation of the International Atomic Energy Agency in 1957. Efforts to conclude an agreement to limit the spread of nuclear weapons did not begin until the early 1960s. Although these efforts stalled in the early 1960s, they renewed once again in 1964, in 1968, governments represented at the Eighteen Nation Disarmament Committee finished negotiations on the text of the NPT. In June 1968, the U. N. General Assembly endorsed the NPT with General Assembly Resolution 2373, and in July 1968, the NPT entered into force in March 1970. The main materials whose generation and distribution is controlled are highly enriched uranium and plutonium, dual-use technology refers to the possibility of military use of civilian nuclear power technology
Nuclear proliferation
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Nuclear weapons
Nuclear proliferation
–
In 2003,
Libya admitted that the nuclear weapons-related material including these
centrifuges, known as Pak-1, were acquired from Pakistan
18.
Nuclear disarmament
–
Nuclear disarmament refers to both the act of reducing or eliminating nuclear weapons and to the end state of a nuclear-weapons-free world, in which nuclear weapons are completely eliminated. There have been many large demonstrations and protests. On June 12,1982, one million people demonstrated in New York Citys Central Park against nuclear weapons and it was the largest anti-nuclear protest and the largest political demonstration in American history. In recent years, some U. S. elder statesmen have also advocated nuclear disarmament, the four have created the Nuclear Security Project to advance this agenda. Organisations such as Global Zero, an international group of 300 world leaders dedicated to achieving nuclear disarmament, have also been established. Proponents of nuclear disarmament say that it would lessen the probability of nuclear war occurring, critics of nuclear disarmament say that it would undermine deterrence. In 1945 in the New Mexico desert, American scientists conducted Trinity, even before the Trinity test, national leaders debated the impact of nuclear weapons on domestic and foreign policy. On August 6,1945, towards the end of World War II, subsequently, the world’s nuclear weapons stockpiles grew. Operation Crossroads was a series of nuclear tests conducted by the United States at Bikini Atoll in the Pacific Ocean in the summer of 1946. Its purpose was to test the effect of weapons on naval ships. Pressure to cancel Operation Crossroads came from scientists and diplomats, manhattan Project scientists argued that further nuclear testing was unnecessary and environmentally dangerous. A Los Alamos study warned the water near a recent surface explosion will be a witchs brew of radioactivity, to prepare the atoll for the nuclear tests, Bikinis native residents were evicted from their homes and resettled on smaller, uninhabited islands where they were unable to sustain themselves. Radioactive fallout from nuclear 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, 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, CND organised Aldermaston marches into the late 1960s when tens of thousands of people took part in the four-day events. On November 1,1961, at the height of the Cold War and it was the largest national womens peace protest of the 20th century. In 1958, Linus Pauling and his wife presented the United Nations with the petition signed by more than 11,000 scientists calling for an end to nuclear-weapon testing, Pauling started the International League of Humanists in 1974
Nuclear disarmament
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The
mushroom cloud over
Hiroshima after the dropping of the atomic bomb nicknamed '
Little Boy ' (1945).
Nuclear disarmament
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The
Campaign for Nuclear Disarmament symbol, designed by
Gerald Holtom in 1958.
Nuclear disarmament
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Mushroom-shaped cloud and water column from the underwater nuclear explosion of July 25, 1946, which was part of
Operation Crossroads.
Nuclear disarmament
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November 1951 nuclear test at the
Nevada Test Site, from
Operation Buster, with a yield of 21 kilotons. It was the first U.S. nuclear field exercise conducted on land; troops shown are 6 mi (9.7 km) from the blast.
19.
Nuclear terrorism
–
Nuclear terrorism refers to an act of terrorism in which a person or people belonging to a terrorist organization detonates a nuclear device. Some definitions of nuclear terrorism include the sabotage of a nuclear facility and/or the detonation of a device, colloquially termed a dirty bomb. It is considered plausible that terrorists could acquire a nuclear weapon, former U. S. President Barack Obama called nuclear terrorism the single most important national security threat that we face. It would destabilize our security, our economies, and our way of life. I was wondering if anything of that kind might be available to use as a defense against that type of use of atomic bombs. Dr. Oppenheimer, If you hired me to walk through the cellars of Washington to see there were atomic bombs, I think my most important tool would be a screwdriver to open the crates. I think that just walking by, swinging a little gadget would not give me the information and this sparked further work on the question of smuggled atomic devices during the 1950s. Discussions of non-state nuclear terrorism among experts go back at least to the 1970s, in 1975 The Economist warned that You can make a bomb with a few pounds of plutonium. By the mid-1980s the power stations may easily be turning out 200,000 lb of the each year. And each year, unless present methods are changed, many thousands of pounds of it will be transferred from one plant to another as it proceeds through the fuel cycle. The dangers of robbery in transit are evident, vigorous co-operation between governments and the International Atomic Energy Agency could, even at this late stage, make the looming perils loom a good deal smaller. And the New York Times commented in 1981 that The Nuclear Emergency Search Teams origins go back to the aftershocks of the Munich Olympic massacre in mid-1972. Until that time, no one in the United States Government had thought seriously about the menace of organized, international terrorism, but it has since been revealed that the physical safeguarding of bomb-grade material against theft was almost scandalously neglected. This discussion took on a public character in the 1980s after NBC aired Special Bulletin. The probability of nuclear terrorism, the experts warned, is increasing, the World Institute for Nuclear Security is an organization which seeks to prevent nuclear terrorism and improve world nuclear security. It works alongside the International Atomic Energy Agency, WINS was formed in 2008, less than a year after a break-in at the Pelindaba nuclear facility in South Africa, which contained enough enriched uranium to make several nuclear bombs. Partners join the GICNT by endorsing the Statement of Principles, a set of nuclear security objectives. GICNT partner nations organize and host workshops, conferences, and exercises to share best practices for implementing the Statement of Principles, the GICNT also holds Plenary meetings to discuss improvements and changes to the partnership
Nuclear terrorism
–
Nuclear weapons
20.
Anti-nuclear movement
–
The anti-nuclear movement is a social movement that opposes various nuclear technologies. Some direct action groups, environmental groups, and professional organisations have identified themselves with the movement at the local, national, the initial objective of the movement was nuclear disarmament, though since the late 1960s opposition has included the use of nuclear power. Many anti-nuclear groups oppose nuclear power and nuclear weapons. The formation of parties in the 1970s and 1980s was often a direct result of anti-nuclear politics. Scientists and diplomats have debated nuclear weapons policy since before the bombings of Hiroshima. The public became concerned about nuclear testing from about 1954. In 1963, many countries ratified the Partial Test Ban Treaty which prohibited atmospheric nuclear testing, some local opposition to nuclear power emerged in the early 1960s, and in the late 1960s some members of the scientific community began to express their concerns. In the early 1970s, there were protests about a proposed nuclear power plant in Wyhl. The project was cancelled in 1975 and anti-nuclear success at Wyhl inspired opposition to power in other parts of Europe. Nuclear power became an issue of public protest in the 1970s. A protest against nuclear power occurred in July 1977 in Bilbao, Spain, following the Three Mile Island accident in 1979, an anti-nuclear protest was held in New York City, involving 200,000 people. The largest protest was held on June 12,1982, when one million people demonstrated in New York City against nuclear weapons, a 1983 nuclear weapons protest in West Berlin had about 600,000 participants. In May 1986, following the Chernobyl disaster, an estimated 150,000 to 200,000 people marched in Rome to protest against the Italian nuclear program. In the US, public opposition preceded the shutdown of the Shoreham, Yankee Rowe, Millstone 1, Rancho Seco, Maine Yankee, and many other nuclear power plants. For many years after the 1986 Chernobyl disaster nuclear power was off the agenda in most countries. The 2011 Japanese nuclear accidents undermined the nuclear power industrys proposed renaissance and revived nuclear opposition worldwide. As of 2016, countries such as Australia, Austria, Denmark, Greece, Malaysia, New Zealand, Germany, Italy, Spain, Sweden and Switzerland are phasing-out nuclear power. Globally, more nuclear reactors have closed than opened in recent years
Anti-nuclear movement
–
120,000 people attended an anti-nuclear protest in
Bonn,
West Germany, on October 14, 1979, following the
Three Mile Island accident.
Anti-nuclear movement
–
Anti-nuclear demonstration in
Colmar, north-eastern France, on October 3, 2009.
Anti-nuclear movement
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Anti-Nuclear Power Plant Rally on 19 September 2011 at
Meiji Shrine complex in Tokyo.
Anti-nuclear movement
–
Women Strike for Peace during the
Cuban Missile Crisis
21.
List of states with nuclear weapons
–
There are eight sovereign states that have successfully detonated nuclear weapons. Five are considered to be nuclear-weapon states under the terms of the Treaty on the Non-Proliferation of Nuclear Weapons, in order of acquisition of nuclear weapons these are, the United States, the Russian Federation, the United Kingdom, France, and China. Since the NPT entered into force in 1970, three states that were not parties to the Treaty have conducted tests, namely India, Pakistan. North Korea had been a party to the NPT but withdrew in 2003, Israel is also widely known to have nuclear weapons, though it maintains a policy of deliberate ambiguity regarding this, and is not known definitively to have conducted a nuclear test. According to the Stockholm International Peace Research Institutes SIPRI Yearbook of 2014, according to Bulletin of the Atomic Scientists Nuclear Notebook 2014, the total number of nuclear weapons worldwide is estimated at 10,144. South Africa developed nuclear weapons but then disassembled its arsenal before joining the NPT, nations that are known or thought to have nuclear weapons are sometimes referred to informally as the nuclear club. This list is known in global politics as the Nuclear Club. With the exception of Russia and the United States these figures are estimates, in particular, under the Strategic Offensive Reductions Treaty thousands of Russian and U. S. nuclear warheads are inactive in stockpiles awaiting processing. The fissile material contained in the warheads can then be recycled for use in nuclear reactors, from a high of 68,000 active weapons in 1985, as of 2016 there are some 4,000 active nuclear warheads and 10,100 total nuclear warheads in the world. Many of the weapons were simply stored or partially dismantled. These five states are also the UN Security Councils permanent members with veto power. It tested the first nuclear weapon on July 16,1945 at 5,30 am and it was the first nation to develop the hydrogen bomb, testing an experimental prototype in 1952 and a deployable weapon in 1954. Throughout the Cold War it continued to modernize and enlarge its nuclear arsenal, the U. S. nuclear arsenal contained 31,175 warheads at its Cold War height. During the Cold War, the United States built approximately 70,000 nuclear warheads, the Soviet Union tested its first nuclear weapon in 1949, in a crash project developed partially with espionage obtained during and after World War II. The Soviet Union was the 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 and it tested its first megaton-range hydrogen bomb in 1955. The Soviet Union also tested the most powerful explosive ever detonated by humans, with a yield of 100 megatons. 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, the Soviet Union built about 55,000 nuclear warheads since 1949
List of states with nuclear weapons
–
An early stage in the "
Trinity " fireball, the first
nuclear explosion, 1945
List of states with nuclear weapons
–
Map of
nuclear-armed states of the world.
List of states with nuclear weapons
–
A
Trident missile launched from a
Royal Navy Vanguard class ballistic missile submarine
List of states with nuclear weapons
–
French nuclear-powered
aircraft carrier Charles de Gaulle (right) and the American nuclear-powered carrier
USS Enterprise (left), each of which carries nuclear-capable
warplanes
22.
Treaty on the Non-Proliferation of Nuclear Weapons
–
Opened for signature in 1968, the treaty entered into force in 1970. As required by the text, after years, NPT Parties met in May 1995. More countries have adhered to the NPT than any other arms limitation and disarmament agreement, four UN member states have never accepted the NPT, three of which are thought to possess nuclear weapons, India, Israel, and Pakistan. In addition, South Sudan, founded in 2011, has not joined, the treaty effectively recognizes five states as nuclear-weapon states, the United States, Russia, the United Kingdom, France, and China. The treaty is reviewed every five years in meetings called Review Conferences of the Parties to the Treaty of Non-Proliferation of Nuclear Weapons. S, government efforts led by Ambassador Thomas Graham Jr. At the time the NPT was proposed, there were predictions of 25–30 nuclear weapon states within 20 years, instead, over forty years later, five states are not parties to the NPT, and they include the only four additional states believed to possess nuclear weapons. Critics argue that the NPT cannot stop the proliferation of weapons or the motivation to acquire them. Several high-ranking officials within the United Nations have said that they can do little to stop states using nuclear reactors to produce nuclear weapons, the NPT consists of a preamble and eleven articles. These pillars are interrelated and mutually reinforcing, with the right to access the benefits of peaceful nuclear technology comes the responsibility of nonproliferation. Progress on disarmament reinforces efforts to strengthen the regime and to enforce compliance with obligations. Under Article III of the Treaty, non-nuclear-weapon states pledge to accept IAEA safeguards to verify that their nuclear activities serve only peaceful purposes. Five states are recognized by NPT as nuclear weapon states, China, France, the Soviet Union, the United Kingdom, and these five nations are also the five permanent members of the United Nations Security Council. These five NWS agree not to nuclear weapons or other nuclear explosive devices and not in any way to assist, encourage. NNWS parties to the NPT agree not to receive, manufacture, however, these undertakings have not been incorporated formally into the treaty, and the exact details have varied over time. The U. S. also had nuclear warheads targeted at North Korea, Article VI of the NPT represents the only binding commitment in a multilateral treaty to the goal of disarmament by the nuclear-weapon states. Under this interpretation, Article VI does not strictly require all signatories to conclude a disarmament treaty. Rather, it requires them to negotiate in good faith. On the other hand, some governments, especially non-nuclear-weapon states belonging to the Non-Aligned Movement, have interpreted Article VIs language as being anything, the ICJ opinion notes that this obligation involves all NPT parties and does not suggest a specific time frame for nuclear disarmament
Treaty on the Non-Proliferation of Nuclear Weapons
–
Recognized nuclear weapon state ratifiers
23.
United States and weapons of mass destruction
–
The United States is known to have possessed three types of weapons of mass destruction, nuclear weapons, chemical weapons, and biological weapons. The U. S. is the country to have used nuclear weapons in combat. It had secretly developed the earliest form of the weapon during the 1940s under the title Manhattan Project. The United States pioneered the development of both the nuclear fission and hydrogen bombs and it was the worlds first and only nuclear power for four years, until the Soviet Union managed to produce its own nuclear weapon. The United States has the second largest number of deployed nuclear weapons in the world, Nuclear weapons have been used twice in combat, two nuclear weapons were used by the United States against Japan during World War II in the atomic bombings of Hiroshima and Nagasaki. Altogether, the two bombings killed 120,000 people and injured another 130,000 while devastating hundreds or thousands of military bases, factories, the U. S. conducted an extensive nuclear testing program. 1,054 tests were conducted between 1945 and 1992, the exact number of nuclear devices detonated is unclear because some tests involved multiple devices while a few failed to explode or were designed not to create a nuclear explosion. The last nuclear test by the United States was on September 23,1992, Air Forces heavy bomber group The United States is one of the five Nuclear Weapons States under the Nuclear Non-Proliferation Treaty, which the U. S. ratified in 1968. On October 13,1999, the U. S. Senate rejected ratification of the Comprehensive Test Ban Treaty, having previously ratified the Partial Test Ban Treaty in 1963. In the early 1990s, the U. S. stopped developing new weapons and now devotes most of its nuclear efforts into stockpile stewardship. The administration of George W. Bush decided in 2003 to engage in research towards a new generation of nuclear weapons. The budget passed by the United States Congress in 2004 eliminated funding for some of this including the bunker-busting or earth-penetrating weapons. The exact number of weapons possessed by the United States is difficult to determine. In its Strategic Arms Reduction Treaty declaration for 2003, the U. S. listed 5968 deployed warheads as defined by START rules, other warheads are in some step of the disassembly process. The exact number as of Sept.30,2009, was 5,113 warheads, in 2002, the United States and Russia agreed in the SORT treaty to reduce their deployed stockpiles to not more than 2,200 warheads each. In 2003, the U. S. rejected Russian proposals to reduce both nations nuclear stockpiles to 1,500 each. In 2007, for the first time in 15 years, the United States built new warheads and these replaced some older warheads as part of the Minuteman III upgrade program. 2007 also saw the first Minuteman III missiles removed from service as part of the drawdown, overall, stockpiles and deployment systems continue to decline in number under the terms of the New START treaty
United States and weapons of mass destruction
–
A
Minuteman III ICBM test launch.
United States and weapons of mass destruction
United States and weapons of mass destruction
–
B-2 Spirit stealth strategic bomber.
United States and weapons of mass destruction
–
USS Kentucky (SSBN-737), an
Ohio-class ballistic missile submarine.
24.
Russia and weapons of mass destruction
–
The figures are, by necessity, only estimates because the exact number of nuclear weapons in each countrys possession is a closely held national secret. In addition to weapons, Russia declared an arsenal of 39,967 tons of chemical weapons in 1997. The Soviet Union ratified the Geneva Protocol on April 5,1928 with reservations, the reservations were later dropped on January 18,2001. Russia is also party to the Biological Weapons Convention and the Chemical Weapons Convention, the Soviet Union had a peak stockpile of 45,000 nuclear warheads in 1988. It is estimated that from 1949 to 1991 the Soviet Union produced approximately 55,000 nuclear warheads, at the dissolution of the Soviet Union in 1991, Soviet nuclear weapons were deployed in four of the new republics, Russia, Ukraine, Belarus and Kazakhstan. Ukraine agreed to give up its weapons to Russia, in exchange for guarantees of Ukrainian territory from Russia, the UK, China and France also made statements in support of the memorandum. The exact number of warheads is a state secret and is therefore a matter of guesswork. According to 2016 data from the New START Treaty Aggregate Numbers of Strategic Offensive Arms facts sheet, on the other hand, Russia is estimated to have roughly 1,500 tactical nuclear weapons, all of which are declared to be in central storage. S. In 2015, informations emerged that Russia may be developing a new up to 100 megatons nuclear torpedo, two potential carrier submarines, the Project 09852 Belgorod, and the Project 09851 Khabarovsk, are new boats laid down in 2012 and 2014 respectively. Status 6 appears to be a deterrent weapon of last resort and it appears to be a torpedo-shaped robotic mini-submarine, that can travel at speeds of 185 km/h. More recent information suggests a top speed of 100 km/h, with a range of 10,000 km and this underwater drone is cloaked by stealth technology to elude acoustic tracking devices. After the Korean War, the Soviet Union transferred nuclear technology and weapons to the Peoples Republic of China as an adversary of the United States, subsequently, the Soviet Union built all the essentials of China’s new military nuclear industry. Russia is one of the five Nuclear Weapons States under the Nuclear Non-Proliferation Treaty, following the dissolution of the Soviet Union in 1991, a number of Soviet-era nuclear warheads remained on the territories of Belarus, Ukraine, and Kazakhstan. It is estimated that the Soviet Union had approximately 45,000 nuclear weapons stockpiled at the time of its collapse, the collapse of the Soviet Union allowed for a warming of relations with NATO. Fears of a nuclear holocaust lessened, in September 1997, the former secretary of the Russian Security Council Alexander Lebed claimed 100 suitcase sized nuclear weapons were unaccounted for. He said he was attempting to inventory the weapons when he was fired by President Boris Yeltsin in October 1996, in 2005, Sergey Sinchenko, a legislator from the Yulia Tymoshenko Bloc, said 250 nuclear weapons were unaccounted for. When comparing documents of nuclear weapons transferred from Ukraine to weapons received by Russia, indeed, several US politicians have expressed worries and promised legislation addressing the threat. In 2002, the United States and Russia agreed to reduce their stockpiles to not more than 2,700 warheads each in the SORT treaty, in 2003, the US rejected Russian proposals to further reduce each nations nuclear stockpiles to 1,500
Russia and weapons of mass destruction
25.
United Kingdom and weapons of mass destruction
–
The United Kingdom possesses, or has possessed, a variety of weapons of mass destruction, including nuclear, biological, and chemical weapons. The United Kingdom is one of the five nuclear weapon states under the Nuclear Non-Proliferation Treaty and has an independent nuclear deterrent. The UK has been estimated to have a stockpile of 120 active nuclear warheads and 215 nuclear warheads in total and it had renounced the use of chemical and biological weapons in 1956 and subsequently destroyed its general stocks. They also manufactured five million linseed-oil cattle cakes with a hole bored into them for addition of anthrax spores between 1942 and mid-1943 and these were to be dropped on Germany using specially designed containers each holding 400 cakes, in a project known as Operation Vegetarian. It was intended that the disease would destroy the German beef and dairy herds, preparations were not complete until early 1944. Operation Vegetarian was only to be used in the event of a German anthrax attack on the United Kingdom, offensive weapons development continued after the war into the 1950s with tests of plague, brucellosis, tularemia and later equine encephalomyelitis and vaccinia viruses. In particular five sets of trials took place at sea using aerosol clouds, Operation Harness off Antigua in 1948-1949. Operation Cauldron off Stornoway in 1952, the trawler Carella unknowingly sailed through a cloud of pneumonic plague bacilli during this trial. It was kept under observation until the incubation period had elapsed. Operation Hesperus off Stornoway in 1953, Operation Ozone off Nassau in 1954. Operation Negation off Nassau in 1954-5, the programme was cancelled in 1956 when the British government renounced the use of biological and chemical weapons. In 1974, biological weapons were banned, and the United Kingdom ratified the Biological, the UK was a signatory of the Hague Conventions which outlawed the use of poison gas in warfare. Britain used a range of gases, originally chlorine and later phosgene, diphosgene. They also used small amounts of the irritant gases chloromethyl chloroformate, chloropicrin, bromacetone. Gases were frequently mixed, for example white star was the given to a mixture of equal volumes of chlorine and phosgene. See Use of poison gas in World War I, historians are divided as to whether or not gas was in fact used. The UK ratified the Geneva Protocol on 9 April 1930, the UK signed the Chemical Weapons Convention on 13 January 1993 and ratified it on 13 May 1996. Despite the signing of the Geneva Protocol, the UK carried out testing of chemical weapons from the early 1930s onwards
United Kingdom and weapons of mass destruction
–
Nuclear weapons
United Kingdom and weapons of mass destruction
United Kingdom and weapons of mass destruction
–
A
Trident missile launched from a submerged
ballistic missile submarine.
26.
France and weapons of mass destruction
–
France is one of the five Nuclear Weapons States under the Nuclear Non-Proliferation Treaty, but is not known to possess or develop any chemical or biological weapons. France was the country to test an independently developed nuclear weapon in 1960. France denies currently having chemical weapons, ratified the Chemical Weapons Convention in 1995, France had also ratified the Geneva Protocol in 1926. France was one of the pioneers, going back to the work of Marie Skłodowska Curie. Curie’s last assistant Bertrand Goldschmidt became the father of the French Bomb, after World War II Frances former position of leadership suffered greatly because of the instability of the Fourth Republic, and the lack of finance available. During the Second World War Goldschmidt invented the method for extracting plutonium while working as part of the British/Canadian team participating in the Manhattan Project. But after the Liberation in 1945, France had to start its own program almost from scratch, nevertheless, the first French reactor went critical in 1948 and small amounts of plutonium were extracted in 1949. There was no commitment to a nuclear weapons program at that time. However, in the 1950s a civilian nuclear program was started. In 1956 a secret Committee for the Military Applications of Atomic Energy was formed, the intervention of the United States in the Suez Crisis that year is credited with convincing France that it needed to accelerate its own nuclear weapons program to remain a global power. With the return of Charles de Gaulle to the presidency of France in the midst of the May 1958 crisis, the decisions to build an atomic bomb were taken. According to Lieutenant Colonel Warner D, progress in nuclear science and technology in France and Israel remained closely linked throughout the early fifties. Israeli scientists probably helped construct the G-1 plutonium production reactor and UP-1 reprocessing plant at Marcoule, in 1957 Euratom was created, and under cover of the peaceful use of nuclear power the French signed deals with Germany and Italy to work together on nuclear weapons development. The West German Chancellor Konrad Adenauer told his cabinet that he wanted to achieve, through EURATOM, as quickly as possible, in 1958 de Gaulle became President and Germany and Italy were excluded. France developed its nuclear and thermonuclear bombs without outside assistance, the United States, however, began providing technical assistance in the early 1970s through the 1980s. The aid was secret, unlike the relationship with the British nuclear program, areas in which the French received help included MIRV, radiation hardening, missile design, intelligence on Soviet anti-missile defences, and advanced computer technology. Because the French program attracted the best brains of the nation, France is understood to have tested neutron or enhanced radiation bombs in the past, apparently leading the field with an early test of the technology in 1967 and an actual neutron bomb in 1980. There were 210 French nuclear tests from 1960 through 1995, seventeen of them were done in the Algerian Sahara between 1960 and 1966, starting in the middle of the Algerian War
France and weapons of mass destruction
–
Nuclear weapons
France and weapons of mass destruction
France and weapons of mass destruction
–
The French nuclear-powered
aircraft carrier Charles de Gaulle and the American nuclear-powered carrier
USS Enterprise (left), each of which carry nuclear-capable
fighter aircraft
27.
China and weapons of mass destruction
–
The Peoples Republic of China has developed and possesses weapons of mass destruction, including chemical and nuclear weapons. The first of Chinas nuclear weapons tests took place in 1964, tests continued until 1996, when China signed the Comprehensive Test Ban Treaty. China has acceded to the Biological and Toxin Weapons Convention in 1984, the number of nuclear warheads in Chinas arsenal is a state secret. There are varying estimates of the size of Chinas arsenal, according to some estimates, the country could more than double the number of warheads on missiles that could threaten the United States by the mid-2020s. Early in 2011, China published a white paper, which repeated its nuclear policies of maintaining a minimum deterrent with a no-first-use pledge. Yet China has yet to define what it means by a minimum deterrent posture and this, together with the fact that it is deploying four new nuclear-capable ballistic missiles, invites concern as to the scale and intention of China’s nuclear upgrade. China signed the Chemical Weapons Convention on January 13,1993, China ratified the CWC on April 25,1997. It has declared only three former chemical production facilities that may have produced gas, phosgene and Lewisite. China was found to have supplied Albania with a stockpile of chemical weapons in the 1970s during the Cold War. However, China was reported to have had a biological weapons program in the 1980s. Kanatjan Alibekov, former director of one of the Soviet germ-warfare programs, Alibekov asserted that Soviet reconnaissance satellites identified a biological weapons laboratory and plant near a site for testing nuclear warheads. US Secretary of State Madeleine Albright expressed her concerns over possible Chinese biological weapon transfers to Iran, in response to this, China issued export control protocols on dual use biological technology in late 2002. Mao Zedong decided to begin a Chinese nuclear-weapons program during the First Taiwan Strait Crisis of 1954–1955 over the Quemoy, while he did not expect to be able to match the large American nuclear arsenal, Mao believed that even a few bombs would increase Chinas diplomatic credibility. Construction of uranium-enrichment plants in Baotou and Lanzhou began in 1958, and a facility in Jiuquan. The Chinese, who preferred to import technology and components to developing them within China, exported uranium to the Soviet Union, and that year, however, Soviet leader Nikita Khruschev told Mao that he planned to discuss arms control with the United States and Britain. China was already opposed to Khruschevs post-Stalin policy of peaceful coexistence, although Soviet officials assured China that it was under the Soviet nuclear umbrella, the disagreements widened the emerging Sino-Soviet split. The Chinese conducted their first nuclear test, code-named 596, on 16 October 1964, Chinas last nuclear test was on July 29,1996. According to the Australian Geological Survey Organization in Canberra, the yield of the 1996 test was 1–5 kilotons and this was Chinas 22nd underground test and 45th test overall
China and weapons of mass destruction
–
Satellite image of the testing site 4 days after China's first atomic bomb test
China and weapons of mass destruction
–
A mock-up of China's first nuclear bomb.
China and weapons of mass destruction
–
Nuclear weapons
China and weapons of mass destruction
–
Medium and
Intercontinental Range Ballistic Missiles. Note: China currently is capable of targeting its nuclear forces throughout the region and most of the world, including the continental United States. Newer systems, such as the
DF-31,
DF-31A, and
JL-2, will give China a more survivable nuclear force.
28.
India and weapons of mass destruction
–
India possesses weapons of mass destruction in the form of nuclear weapons and, in the past, chemical weapons. In 1999 India was estimated to have 800 kg of separated reactor-grade plutonium, with an amount of 8300 kg of civilian plutonium. India is not a signatory to the 1968 Nuclear Non-Proliferation Treaty, India has signed and ratified the Biological Weapons Convention and the Chemical Weapons Convention. India is also a member of the Missile Technology Control Regime, India has a well-developed biotechnology infrastructure that includes numerous pharmaceutical production facilities and bio-containment laboratories for working with lethal pathogens. It also has highly qualified scientists with expertise in infectious diseases, some of Indias facilities are being used to support research and development for biological weapons defence purposes. India has ratified the Biological Weapons Convention and pledges to abide by its obligations, there is no clear evidence, circumstantial or otherwise, that directly points toward an offensive BW program. India does possess the capability and infrastructure to launch an offensive BW program. In terms of delivery, India also possesses the capability to produce aerosols and has numerous potential delivery systems ranging from crop dusters to sophisticated ballistic missiles. No information exists in the public domain suggesting interest by the Indian government in delivery of biological agents by these or any other means. To reiterate the latter point, in October 2002, the then President Dr. A. P. J. Abdul Kalam asserted that India will not make biological weapons and it is cruel to human beings. In 1992, India signed the Chemical Weapons Convention, stating that it did not have chemical weapons, by doing this India became one of the original signatories of the CWC in 1993, and ratified it on 2 September 1996. Others suggested that the fact that India has found chemical weapons dispensable highlighted its confidence in the weapons system at its command. In June 1997, India declared its stock of chemical weapons, India informed the United Nations in May 2009 that it had destroyed its stockpile of chemical weapons in compliance with the international Chemical Weapons Convention. With this India has become third country after South Korea and Albania to do so and this was cross-checked by inspectors of the United Nations. India has a commercial chemical industry, and produces the bulk of its own chemicals for domestic consumption. Homi Bhabha when he founded the research centre, the Institute of Fundamental Research. India first tested a device in 1974, which it called a peaceful nuclear explosion. The test used plutonium produced in the Canadian-supplied CIRUS reactor, and this also stimulated the early work of the Nuclear Suppliers Group
India and weapons of mass destruction
–
The Indian Army's Agni II missile on parade.
India and weapons of mass destruction
India and weapons of mass destruction
–
The
Indian Air Force 's
Jaguar attack aircraft are believed to have a secondary nuclear-strike role.
India and weapons of mass destruction
–
Conceptual drawing of the INS Arihant.
29.
Nuclear weapons and Israel
–
It is one of four nuclear-armed countries not recognized as a Nuclear Weapons State by the Nuclear Non-Proliferation Treaty, the others being India, Pakistan and North Korea. Israel maintains a policy known as nuclear ambiguity, Israel has refused to sign the NPT despite international pressure to do so, and has stated that signing the NPT would be contrary to its national security interests. Additionally, Israel has made efforts to deny other regional actors the ability to acquire their own nuclear weapons. The counter-proliferation, preventive strike Begin Doctrine added another dimension to Israels existing nuclear policy, Israel remains the only country in the Middle East believed to possess them. Israel is alleged to have built its first nuclear weapon in December 1966, but it is not publicly confirmed. In 1987, an unclassified US DoD report stated that As far as nuclear technology is concerned and it should be noted that the Israelis are developing the kind of codes which will enable them to make hydrogen bombs. Estimates as to the size of the Israeli nuclear arsenal vary between 75 and 400 nuclear warheads, former U. S. officials Jimmy Carter and Colin Powell have stated that Israel has 200 or more than 300 nuclear warheads. Israels first Prime Minister David Ben-Gurion was nearly obsessed with obtaining nuclear weapons to prevent the Holocaust from recurring. He stated, What Einstein, Oppenheimer, and Teller, the three of them are Jews, made for the United States, could also be done by scientists in Israel, for their own people. Ben-Gurion decided to recruit Jewish scientists from abroad even before the end of the 1948 Arab–Israeli War that established Israels independence, in 1949 a unit of the Israel Defense Forces Science Corps, known by the Hebrew acronym HEMED GIMMEL, began a two-year geological survey of the Negev. In early 1952 Hemed Gimmel was moved from the IDF to the Ministry of Defense and was reorganized as the Division of Research and that June, Bergmann was appointed by Ben-Gurion to be the first chairman of the Israel Atomic Energy Commission. The techniques were two more advanced than American efforts. Bergmann, who was interested in increasing nuclear cooperation with the French, although they were never commercialized, it was a consequential step for future French-Israeli cooperation. In addition, Israeli scientists probably helped construct the G-1 plutonium production reactor, France and Israel had close relations in many areas. At the same time Israeli scientists were also observing Frances own nuclear program, According to Lieutenant Colonel Warner D. Progress in nuclear science and technology in France and Israel remained closely linked throughout the early fifties, furthermore, according to Farr, There were several Israeli observers at the French nuclear tests and the Israelis had unrestricted access to French nuclear test explosion data. The French justified their decision to provide Israel a nuclear reactor by claiming it was not without precedent, in September 1955 Canada publicly announced that it would help the Indian government build a heavy-water research reactor, the CIRUS, for peaceful purposes. In exchange, France would provide the nuclear reactor as the basis for the Israeli nuclear weapons program, Shimon Peres, sensing the opportunity on the nuclear reactor, accepted
Nuclear weapons and Israel
–
Nuclear weapons
Nuclear weapons and Israel
Nuclear weapons and Israel
–
Completed Dimona complex as seen by US
Corona satellite on November 11, 1968
Nuclear weapons and Israel
–
Mordechai Vanunu 's photograph of a
Negev Nuclear Research Center glove box containing nuclear materials in a model bomb assembly, one of about 60 photographs he later gave to the British press
30.
Pakistan and weapons of mass destruction
–
Pakistan is one of nine states to possess nuclear weapons, and the only Muslim majority country to do so. The Kahuta Project started under the supervision of a board that oversaw the activities of KRL. The Board consisted of A G N Kazi, Ghulam Ishaq Khan, and Agha Shahi, Ghulam Ishaq Khan and General Tikka Khan appointed military engineer Major General Ali Nawab to the program. Eventually, the passed to Lt General Zahid Ali Akbar in President General Muhammad Zia-ul-Haqs Administration. Moderate uranium enrichment for the production of material was achieved at KRL by April 1978. Pakistans nuclear weapons development was in response to the loss of East Pakistan in 1971s Bangladesh Liberation War, Bhutto called a meeting of senior scientists and engineers on 20 January 1972, in Multan, which came to known as Multan meeting. In December 1972, Abdus Salam led the establishment of Theoretical Physics Group as he called scientists working at ICTP to report to Munir Ahmad Khan and this marked the beginning of Pakistans pursuit of nuclear deterrence capability. Finally, on 28 May 1998, a few weeks after Indias second nuclear test, Pakistan detonated five nuclear devices in the Ras Koh Hills in the Chagai district, Balochistan. This operation was named Chagai-I by Pakistan, the underground iron-steel tunnel having been long-constructed by provincial martial law administrator General Rahimuddin Khan during the 1980s. The last test of Pakistan was conducted at the sandy Kharan Desert under the codename Chagai-II, also in Balochistan, Pakistans fissile material production takes place at Nilore, Kahuta, and Khushab/Jauharabad, where weapons-grade plutonium is refined. Pakistan thus became the country in the world to successfully develop. Although, according to a sent by A. Q. Khan to General Zia, the capability to detonate a bomb using highly enriched uranium as fissile material produced at KRL had been achieved by KRL in 1984. After the Partition of India in 1947, India and Pakistan have been in conflict over several issues, including the territory of Jammu. The uneasy relationships with India, Afghanistan, the former Soviet Union, on 8 December 1953, Pakistan media welcomed the U. S. Atoms for Peace initiatives, followed by the establishment of Pakistan Atomic Energy Commission in 1956, in 1953, Foreign minister Muhammad Zafarullah Khan publicly stated that Pakistan does not have a policy towards the atom bombs. Before 1971, Pakistans nuclear development was peaceful but an effective deterrent against India, Pakistans nuclear energy programme was established and started in 1956 following the establishment of PAEC. Pakistan became a participant in U. S. President Eisenhowers Atoms for Peace program, pAECs first chairman was Dr. Nazir Ahmad
Pakistan and weapons of mass destruction
–
Nuclear weapons
Pakistan and weapons of mass destruction
Pakistan and weapons of mass destruction
–
The televised screen-shot of
Chagai-I on 28 May 1998.
Pakistan and weapons of mass destruction
–
Pakistani Missiles on display at the
IDEAS 2008 defence exhibition in
Karachi, Pakistan.
31.
North Korea and weapons of mass destruction
–
North Korea and weapons of mass destruction concerns North Korea, which declared in 2009 that it had developed a nuclear weapon, and possessed a small stockpile of relatively simple nuclear weapons. North Korea may also have a chemical weapon and/or biological weapons capability, since 2003, North Korea is no longer a party to the Treaty on the Non-Proliferation of Nuclear Weapons. The nuclear program can be traced back to about 1962, when North Korea committed itself to what it called all-fortressization, in 1963, North Korea asked the Soviet Union for help in developing nuclear weapons, but was refused. The Soviet Union agreed to help North Korea develop a nuclear energy program. Later, China, after its nuclear tests, similarly rejected North Korean requests for help with developing nuclear weapons, in 1979 North Korea indigenously began to build in Yongbyon a second research reactor, an ore processing plant and a fuel rod fabrication plant. North Koreas nuclear weapons program dates back to the 1980s, in 1985 North Korea ratified the NPT, but did not conclude the required safeguards agreement with the IAEA until 1992. In early 1993, while verifying North Koreas initial declaration, the IAEA concluded that there was strong evidence this declaration was incomplete, when North Korea refused the requested special inspection, the IAEA reported its non-compliance to the UN Security Council. In 1993, North Korea announced its withdrawal from the NPT, under the 1994 Agreed Framework, the U. S. government agreed to facilitate the supply of two light water reactors to North Korea in exchange for North Korean disarmament. Such reactors are considered more proliferation-resistant than North Koreas graphite-moderated reactors, implementation of the Agreed Framework floundered, and in 2002 the Agreed Framework fell apart, with each side blaming the other for its failure. By 2002, Pakistan had admitted that North Korea had gained access to Pakistans nuclear technology in the late 1990s, on October 9,2006, North Korea announced it had successfully conducted its first nuclear test. An underground nuclear explosion was detected, its yield was estimated as less than a kiloton, on January 6,2007, the North Korean government further confirmed that it had nuclear weapons. In April 2009, reports surfaced that North Korea has become a fully fledged nuclear power, on May 25,2009, North Korea conducted a second nuclear test, resulting in an explosion estimated to be between 2 and 7 kilotons. The 2009 test, like the 2006 test, is believed to have occurred at Mantapsan, Kilju County, on February 11,2013, the U. S. Geological Survey detected a magnitude 5.1 seismic disturbance, reported to be a third underground nuclear test. North Korea has officially reported it as a nuclear test with a lighter warhead that delivers more force than before. Multiple South Korean sources estimate the yield at 6–9 kilotons, while the German Federal Institute for Geosciences, however, the German estimates has since revised to a yield equivalent of 14 kt when they published their estimations in 2016 Jan. On January 6,2016 in Korea, the United States Geological Survey detected a magnitude 5.1 seismic disturbance, North Korea claimed that this test involved a hydrogen bomb. This claim has not been verified, within hours, many nations and organizations had condemned the test. Expert U. S. analysts do not believe that a bomb was detonated
North Korea and weapons of mass destruction
–
Nuclear weapons
North Korea and weapons of mass destruction
North Korea and weapons of mass destruction
–
5 MWe experimental reactor at
Yongbyon Nuclear Scientific Research Center
32.
South Africa and weapons of mass destruction
–
From the 1960s to the 1980s, South Africa pursued research into weapons of mass destruction, including nuclear, biological, and chemical weapons. The country has been a signatory of the Biological Weapons Convention since 1975, the Treaty on the Non-Proliferation of Nuclear Weapons since 1991, and the Chemical Weapons Convention since 1995. In 1957, South Africa reached an understanding with the United States after signing a 50-year collaboration under the U. S. -sanctioned programme, the Atoms for Peace. The treaty concluded the South African acquisition of a nuclear research reactor. The SAFARI-2 reactor was intended to be moderated by heavy water, in 1969, the project was abandoned by the South African government because the reactor was draining resources from the uranium enrichment program that was initiated in 1967. South Africa began focusing on the success of its enrichment programme which was seen by its scientists as easier compared to plutonium. South Africa was able to mine uranium ore domestically, and used aerodynamic nozzle enrichment techniques to produce weapons-grade material. The South African and Pakistani scientists studied the use of aerodynamic-jet nozzle process to enrich the fuel at the University of Birmingham and it is not clear how much knowledge they gained and to what extent they cooperated. South Africa gained sufficient experience with the technology to capitalize on the promotion of the U. S. governments Peaceful Nuclear Explosions program. Finally in 1971, South African minister of mines Carl de Wet gave approval of the countrys own PNE programme with the stated objective of using PNEs in the mining industry. The date when the South African PNE programme transformed into a program is a matter of some dispute. South Africa developed a small finite deterrence arsenal of gun-type fission weapons in the 1980s, six were constructed and another was under construction at the time the program ended. South Africa only produced a weapon after Armscor took over production. In 1982, Armscor built the first operational weapon, code-named Hobo and this device reportedly had a yield of 6 kilotons of TNT. It was eventually dissembled and the warhead reused in a production model bomb, Armscor then built a series of pre-production and production models under the code-name HAMERKOP after a bird. While Hobo/Cabot were not functional, the HAMERKOP series were smart television-guided glide bombs, the South African Atomic Energy Board selected a test site in the Kalahari Desert at the Vastrap weapons range north of Upington. Two test shafts were completed in 1976 and 1977, one shaft was 385 metres deep, the other,216 metres. In 1977, the AEB established its own high-security weapons research and development facilities at Pelindaba, in mid-1977, the AEB produced a gun-type device—without a highly enriched uranium core
South Africa and weapons of mass destruction
–
Spare bomb casings from South Africa's nuclear weapon programme
South Africa and weapons of mass destruction
South Africa and weapons of mass destruction
–
Nuclear weapons
South Africa and weapons of mass destruction
–
SAAF Canberra T.4
33.
Nuclear fallout
–
It commonly refers to the radioactive dust and ash created when a nuclear weapon explodes, but such dust can also originate from a damaged nuclear plant. Fallout may get entrained with the products of a pyrocumulus cloud and this radioactive dust, usually consisting of fission products mixed with bystanding atoms that are neutron activated by exposure, is a highly dangerous kind of radioactive contamination. An air burst can eventually produce worldwide fallout, a ground burst can produce possibly much more severe, local fallout. These particles may be drawn up into the stratosphere, particularly if the explosive yield exceeds 10 kt. Initially little was known about the dispersion of nuclear fallout on a global scale, the AEC assumed that fallout would be dispersed evenly across the globe by atmospheric winds and gradually settle to the Earths surface after weeks, months, and even years as worldwide fallout. This hazard is less pertinent than local fallout, which is of much greater immediate operational concern, in a land or water surface burst, heat vaporizes large amounts of earth or water, which is drawn up into the radioactive cloud. This material becomes radioactive when it condenses with fission products and other radiocontaminants that have become neutron-activated, the table below summarizes the abilities of common isotopes to form fallout. Some radiation taints large amounts of land and drinking water causing formal mutations throughout animal and human life. The larger particles spill out of the stem and cascade down the outside of the fireball in a downdraft even as the cloud rises, more than half the total bomb debris lands on the ground within about 24 hours as local fallout. Chemical properties of the elements in the control the rate at which they are deposited on the ground. Severe local fallout contamination can extend far beyond the blast and thermal effects, the ground track of fallout from an explosion depends on the weather from the time of detonation onwards. In stronger winds, fallout travels faster but takes the time to descend, so although it covers a larger path. Thus, the width of the pattern for any given dose rate is reduced where the downwind distance is increased by higher winds. The total amount of activity deposited up to any time is the same irrespective of the wind pattern. But thunderstorms can bring down activity as rain more rapidly than dry fallout, particularly if the cloud is low enough to be below, or mixed with. There are two considerations for the location of an explosion, height and surface composition. A nuclear weapon detonated in the air, called an air burst, in case of water surface bursts, the particles tend to be rather lighter and smaller, producing less local fallout but extending over a greater area. The particles contain mostly sea salts with some water, these can have a cloud seeding effect causing local rainout and areas of high local fallout
Nuclear fallout
–
Nuclear weapons
Nuclear fallout
–
Comparison of fallout gamma dose and dose rate contours for a 1 Mt fission land surface burst, based on DELFIC calculations. Because of radioactive decay, the dose rate contours contract after fallout has arrived, but dose contours continue to grow
Nuclear fallout
–
Fallout shelter sign on a building in
New York City.
Nuclear fallout
–
Following the detonation of the first atomic bomb,
pre-war steel became a valuable commodity for scientists since it was the only steel not contaminated by radiation.
34.
Civil defense
–
Civil defense, civil defence or civil protection is an effort to protect the citizens of a state from military attacks and natural disasters. It uses the principles of operations, prevention, mitigation, preparation, response, or emergency evacuation. Programs of this sort were initially discussed at least as early as the 1920s and were implemented in some countries during the 1930s as the threat of war and it became widespread after the threat of nuclear weapons was realized. Since the end of the Cold War, the focus of civil defense has largely shifted from military attack to emergencies, in some countries, civil defense is seen as a key part of total defense. For example, in Sweden, the Swedish word totalförsvar refers to the commitment of a range of resources of the nation to its defense - including to civil protection. Respectively, some countries may have or have had military-organized civil defense units as part of their armed forces or as a paramilitary service, the advent of civil defence was stimulated by the experience of the bombing of civilian areas during the First World War. The bombing of the United Kingdom began on 19 January 1915 when German zeppelins dropped bombs on the Great Yarmouth area, German bombing operations of the First World War were surprisingly effective, especially after the Gotha bombers surpassed the zeppelins. The most devastating raids inflicted 121 casualties for each ton of bombs dropped, the Committee produced figures estimating that in London there would be 9,000 casualties in the first two days and then a continuing rate of 17,500 casualties a week. It was believed there would be total chaos and panic. To control the population harsh measures were proposed, bringing London under almost military control, a different government department proposed setting up camps for refugees for a few days before sending them back to London. A special government department, the Civil Defence Service, was established by the Home Office in 1935 and its remit included the pre-existing ARP as well as wardens, firemen, fire watchers, rescue, first aid post, stretcher party and industry. Over 1.9 million people served within the CD, nearly 2,400 lost their lives to enemy action, the organisation of civil defence was the responsibility of the local authority. Volunteers were ascribed to different units depending on experience or training, each local civil defence service was divided into several sections. Wardens were responsible for reconnaissance and reporting, and leadership, organisation, guidance. Wardens would also advise survivors of the locations of rest and food centres, Rescue Parties were required to assess and then access bombed-out buildings and retrieve injured or dead people. In addition they would turn off gas, electricity and water supplies, medical services, including First Aid Parties, provided on the spot medical assistance. The expected stream of information that would be generated during an attack was handled by Report, a local headquarters would have an ARP controller who would direct rescue, first aid and decontamination teams to the scenes of reported bombing. If local services were deemed insufficient to deal with the incident then the controller could request assistance from surrounding boroughs
Civil defense
–
British
First World War poster, bringing attention to the threat posed by aerial bombardment from German
Zeppelins.
Civil defense
–
The international distinctive sign of civil defense, defined by the rules of
international humanitarian law and to be used as a
protective sign
Civil defense
–
Air Raid Warden testing his equipment in Brisbane in October 1942.
Civil defense
–
Anderson shelters were widely distributed in Britain by civil defence authorities, in preparation for aerial bombardment.
35.
Cold War
–
The Cold War was a state of geopolitical tension after World War II between powers in the Eastern Bloc and powers in the Western Bloc. Historians do not fully agree on the dates, but a common timeframe is the period between 1947, the year the Truman Doctrine was announced, and 1991, the year the Soviet Union collapsed. The term cold is used there was no large-scale fighting directly between the two sides, although there were major regional wars, known as proxy wars, supported by the two sides. The Cold War split the temporary alliance against Nazi Germany, leaving the Soviet Union. The USSR was a Marxist–Leninist state ruled by its Communist Party and secret police, the Party controlled the press, the military, the economy and all organizations. In opposition stood the West, dominantly democratic and capitalist with a free press, a small neutral bloc arose with the Non-Aligned Movement, it sought good relations with both sides. The two superpowers never engaged directly in full-scale armed combat, but they were armed in preparation for a possible all-out nuclear world war. The first phase of the Cold War began in the first two years after the end of the Second World War in 1945, the Berlin Blockade was the first major crisis of the Cold War. With the victory of the communist side in the Chinese Civil War and the outbreak of the Korean War, the USSR and USA competed for influence in Latin America, and the decolonizing states of Africa and Asia. Meanwhile, the Hungarian Revolution of 1956 was stopped by the Soviets, the expansion and escalation sparked more crises, such as the Suez Crisis, the Berlin Crisis of 1961, and the Cuban Missile Crisis of 1962. The USSR crushed the 1968 Prague Spring liberalization program in Czechoslovakia, détente collapsed at the end of the decade with the beginning of the Soviet–Afghan War in 1979. The early 1980s were another period of elevated tension, with the Soviet downing of Korean Air Lines Flight 007, the United States increased diplomatic, military, and economic pressures on the Soviet Union, at a time when the communist state was already suffering from economic stagnation. In the mid-1980s, the new Soviet leader Mikhail Gorbachev introduced the reforms of perestroika and glasnost. Pressures for national independence grew stronger in Eastern Europe, especially Poland, Gorbachev meanwhile refused to use Soviet troops to bolster the faltering Warsaw Pact regimes as had occurred in the past. The result in 1989 was a wave of revolutions that peacefully overthrew all of the communist regimes of Central, the Communist Party of the Soviet Union itself lost control and was banned following an abortive coup attempt in August 1991. This in turn led to the dissolution of the USSR in December 1991. The United States remained as the only superpower. The Cold War and its events have left a significant legacy and it is often referred to in popular culture, especially in media featuring themes of espionage and the threat of nuclear warfare
Cold War
–
Photograph of the
Berlin Wall taken from the West side. The Wall was built in 1961 to prevent East Germans from fleeing and to stop an economically disastrous drain of workers. It was a symbol of the Cold War and its fall in 1989 marked the approaching end of the war.
Cold War
–
Allied troops in
Vladivostok, August 1918, during the
Allied intervention in the
Russian Civil War.
Cold War
–
The "
Big Three " at the Yalta Conference:
Winston Churchill,
Franklin D. Roosevelt and
Joseph Stalin, 1945.
36.
Radioactivity
–
A material containing such unstable nuclei is considered radioactive. Certain highly excited short-lived nuclear states can decay through neutron emission, or more rarely, however, for a collection of atoms, the collections expected decay rate is characterized in terms of their measured decay constants or half-lives. This is the basis of radiometric dating, the half-lives of radioactive atoms have no known upper limit, spanning a time range of over 55 orders of magnitude, from nearly instantaneous to far longer than the age of the universe. A radioactive nucleus with spin can have no defined orientation. If there are multiple particles produced during a single decay, as in decay, their relative angular distribution. Such a parent process could be a previous decay, or a nuclear reaction, the decaying nucleus is called the parent radionuclide, and the process produces at least one daughter nuclide. Except for gamma decay or internal conversion from an excited state. When the number of changes, an atom of a different chemical element is created. The first decay processes to be discovered were alpha decay, beta decay, alpha decay occurs when the nucleus ejects an alpha particle. This is the most common process of emitting nucleons, but highly excited nuclei can eject single nucleons, or in the case of cluster decay, specific light nuclei of other elements. Beta decay occurs when the nucleus emits an electron or positron, the nucleus may capture an orbiting electron, causing a proton to convert into a neutron in a process called electron capture. All of these result in a well-defined nuclear transmutation. By contrast, there are radioactive decay processes that do not result in a nuclear transmutation, another type of radioactive decay results in products that vary, appearing as two or more fragments of the original nucleus with a range of possible masses. For a summary table showing the number of stable and radioactive nuclides in each category, there are 29 naturally occurring chemical elements on Earth that are radioactive. They are those that contain 34 radionuclides that date before the time of formation of the solar system, well-known examples are uranium and thorium, but also included are naturally occurring long-lived radioisotopes, such as potassium-40. Radioactivity was discovered in 1896 by the French scientist Henri Becquerel and these materials glow in the dark after exposure to light, and he suspected that the glow produced in cathode ray tubes by X-rays might be associated with phosphorescence. He wrapped a photographic plate in black paper and placed various phosphorescent salts on it, all results were negative until he used uranium salts. The uranium salts caused a blackening of the plate in spite of the plate being wrapped in black paper and these radiations were given the name Becquerel Rays
Radioactivity
–
Pierre and Marie Curie in their Paris laboratory, before 1907
Radioactivity
–
Alpha decay is one type of radioactive decay, in which an atomic nucleus emits an
alpha particle, and thereby transforms (or "decays") into an atom with a
mass number decreased by 4 and
atomic number decreased by 2.
Radioactivity
–
Taking an X-ray image with early
Crookes tube apparatus in 1896. The Crookes tube is visible in the centre. The standing man is viewing his hand with a
fluoroscope screen; this was a common way of setting up the tube. No precautions against radiation exposure are being taken; its hazards were not known at the time.
Radioactivity
–
Gamma-ray energy spectrum of uranium ore (inset). Gamma-rays are emitted by decaying
nuclides, and the gamma-ray energy can be used to characterize the decay (which nuclide is decaying to which). Here, using the gamma-ray spectrum, several nuclides that are typical of the decay chain of 238 U have been identified: 226 Ra, 214 Pb, 214 Bi.
37.
Pumice
–
Pumice, called pumicite in its powdered or dust form, is a volcanic rock that consists of highly vesicular rough textured volcanic glass, which may or may not contain crystals. Scoria is another vesicular volcanic rock that differs from pumice in having larger vesicles, thicker walls and being dark colored. Pumice is created when super-heated, highly pressurized rock is violently ejected from a volcano, the unusual foamy configuration of pumice happens because of simultaneous rapid cooling and rapid depressurization. The depressurization creates bubbles by lowering the solubility of gases that are dissolved in the lava, the simultaneous cooling and depressurization freezes the bubbles in a matrix. Eruptions under water are cooled and the large volume of pumice created can be a shipping hazard for cargo ships. Pumice is composed of highly microvesicular glass pyroclastic with very thin and it is commonly, but not exclusively of silicic or felsic to intermediate in composition, but basaltic and other compositions are known. Pumice is commonly pale in color, ranging from white, cream, blue or grey and it forms when volcanic gases exsolving from viscous magma form bubbles that remain within the viscous magma as it cools to glass. Pumice is a product of explosive eruptions and commonly forms zones in upper parts of silicic lavas. Pumice has a porosity of 90%, and initially floats on water. Scoria differs from pumice in being denser, with larger vesicles and thicker vesicle walls, it sinks rapidly. The difference is the result of the viscosity of the magma that forms scoria. When larger amounts of gas are present, the result is a variety of pumice known as pumicite. Pumice is considered a glass because it has no crystal structure, pumice varies in density according to the thickness of the solid material between the bubbles, many samples float in water. After the explosion of Krakatoa, rafts of pumice drifted through the Pacific Ocean for up to 20 years, in fact, pumice rafts disperse and support several marine species. In 1979,1984 and 2006, underwater volcanic eruptions near Tonga created large pumice rafts, there are two main forms of vesicles. Most pumice contains tubular microvesicles that can impart a silky or fibrous fabric, the elongation of the microvesicles occurs due to ductile elongation in the volcanic conduit or, in the case of pumiceous lavas, during flow. The other form of vesicles are subspherical to spherical and result from high pressure during eruption. Pumice is widely used to make concrete or insulative low-density cinder blocks
Pumice
–
Specimen of highly porous pumice from
Teide volcano on
Tenerife,
Canary Islands.
Density of specimen approximately 0.25 g/cm 3; scale in
centimeters.
Pumice
–
Illustrates the porous nature in detail.
Pumice
–
Rocks from the
Bishop tuff, uncompressed with pumice on left; compressed with
fiamme on right.
Pumice
–
A 15 centimeter (6 inch) piece of pumice supported by a rolled-up U.S. 20-dollar bill demonstrates its very low density.
38.
Alpha particle
–
Alpha particles consist of two protons and two neutrons bound together into a particle identical to a helium nucleus. They are generally produced in the process of decay. Alpha particles are named after the first letter in the Greek alphabet, the symbol for the alpha particle is α or α2+. Because they are identical to helium nuclei, they are sometimes written as He2+ or 4 2He2+ indicating a helium ion with a +2 charge. If the ion gains electrons from its environment, the particle can be written as a normal helium atom 4 2He. Some science authors may use doubly ionized helium nuclei and alpha particles as interchangeable terms, the nomenclature is not well defined, and thus not all high-velocity helium nuclei are considered by all authors to be alpha particles. As with beta and gamma rays/particles, the used for the particle carries some mild connotations about its production process and energy. Thus, alpha particles may be used as a term when referring to stellar helium nuclei reactions. A higher energy version of alphas than produced in alpha decay is a product of an uncommon nuclear fission result called ternary fission. However, helium nuclei produced by particle accelerators are less likely to be referred to as alpha particles, alpha particles, like helium nuclei, have a net spin of zero. Due to the mechanism of their production in standard alpha radioactive decay, alpha particles generally have an energy of about 5 MeV. They are a highly ionizing form of radiation, and have low penetration depth. They are able to be stopped by a few centimeters of air, however, so-called long range alpha particles from ternary fission are three times as energetic, and penetrate three times as far. To a lesser extent, this is true of very high-energy helium nuclei produced by particle accelerators. The best-known source of particles is alpha decay of heavier atoms. When an atom emits an alpha particle in alpha decay, the mass number decreases by four due to the loss of the four nucleons in the alpha particle. The atomic number of the atom goes down by two, as a result of the loss of two protons – the atom becomes a new element. Examples of this sort of nuclear transmutation are when uranium becomes thorium, or radium becomes radon gas, alpha particles are commonly emitted by all of the larger radioactive nuclei such as uranium, thorium, actinium, and radium, as well as the transuranic elements
Alpha particle
–
A physicist observes alpha particles from the decay of a polonium source in a
cloud chamber
Alpha particle
–
Alpha decay
Alpha particle
–
The trace of a single alpha particle obtained by nuclear physicist Wolfhart Willimczik with his spark chamber specially made for alpha particle.
39.
Beta particle
–
Two forms of beta decay, β− and β+, respectively produce electrons and positrons. Beta particles are a type of ionizing radiation, the neutron turns into a proton through the emission of a virtual W− boson. At the quark level, W− emission turns a down quark into an up quark, the virtual W− boson then decays into an electron and an antineutrino. Beta decay commonly occurs among the neutron-rich fission byproducts produced in nuclear reactors, free neutrons also decay via this process. Both of these contribute to the copious numbers of beta rays. The daughter nucleus is a lower-energy state, of the three common types of radiation given off by radioactive materials, alpha, beta and gamma, beta has the medium penetrating power and the medium ionising power. Although the beta particles given off by different radioactive materials vary in energy, shielding composed of materials with lower atomic weight generates gammas with lower energy, making such shields somewhat more effective per unit mass than ones made of high-Z materials such as lead. Being composed of charged particles, beta radiation is more strongly ionizing than gamma radiation, when passing through matter, a beta particle is decelerated by electromagnetic interactions and may give off bremsstrahlung x-rays. In water, beta radiation from nuclear fission products typically exceeds the speed of light in that material. The intense beta radiation from the rods of pool-type reactors can thus be visualized through the transparent water that covers. The ionizing or excitation effects of particles on matter are the fundamental processes by which radiometric detection instruments detect. The ionization of gas is used in ion chambers and Geiger-Muller counters, beta particles can be used to treat health conditions such as eye and bone cancer and are also used as tracers. Strontium-90 is the material most commonly used to produce beta particles, beta particles are also used in quality control to test the thickness of an item, such as paper, coming through a system of rollers. Some of the radiation is absorbed while passing through the product. If the product is too thick or thin, a correspondingly different amount of radiation will be absorbed. A computer program monitoring the quality of the paper will then move the rollers to change the thickness of the final product. An illumination device called a betalight contains tritium and a phosphor, as tritium decays, it emits beta particles, these strike the phosphor, causing the phosphor to give off photons, much like the cathode ray tube in a television. Beta-plus decay of a radioactive isotope is the source of the positrons used in positron emission tomography
Beta particle
–
Blue
Cherenkov radiation light being emitted from a
TRIGA reactor pool is due to high-speed beta particles traveling faster than the speed of light (phase velocity) in water (which is 75% of the speed of light in vacuum).
Beta particle
–
Alpha radiation consists of
helium nuclei and is readily stopped by a sheet of paper. Beta radiation, consisting of
electrons or
positrons, is halted by an aluminum plate. Gamma radiation is damped by lead.
40.
Gamma ray
–
Gamma ray, denoted by the lower-case Greek letter gamma, is penetrating electromagnetic radiation of a kind arising from the radioactive decay of atomic nuclei. It consists of photons in the highest observed range of photon energy, paul Villard, a French chemist and physicist, discovered gamma radiation in 1900 while studying radiation emitted by radium. In 1903, Ernest Rutherford named this radiation gamma rays, Rutherford had previously discovered two other types of radioactive decay, which he named alpha and beta rays. Gamma rays are able to ionize atoms, and are thus biologically hazardous. The decay of a nucleus from a high energy state to a lower energy state. Natural sources of gamma rays on Earth are observed in the decay of radionuclides. There are rare terrestrial natural sources, such as lightning strikes and terrestrial gamma-ray flashes, However, a large fraction of such astronomical gamma rays are screened by Earths atmosphere and can only be detected by spacecraft. Gamma rays typically have frequencies above 10 exahertz, and therefore have energies above 100 keV and wavelengths less than 10 picometers, However, this is not a strict definition, but rather only a rule-of-thumb description for natural processes. Electromagnetic radiation from radioactive decay of nuclei is referred to as gamma rays no matter its energy. This radiation commonly has energy of a few hundred keV, in astronomy, gamma rays are defined by their energy, and no production process needs to be specified. The energies of gamma rays from astronomical sources range to over 10 TeV, a notable example is the extremely powerful bursts of high-energy radiation referred to as long duration gamma-ray bursts, of energies higher than can be produced by radioactive decay. These bursts of gamma rays are thought to be due to the collapse of stars called hypernovae, the first gamma ray source to be discovered historically was the radioactive decay process called gamma decay. In this type of decay, a nucleus emits a gamma ray almost immediately upon formation. Paul Villard, a French chemist and physicist, discovered gamma radiation in 1900, However, Villard did not consider naming them as a different fundamental type. Rutherford also noted that gamma rays were not deflected by a field, another property making them unlike alpha. Gamma rays were first thought to be particles with mass, like alpha, Rutherford initially believed that they might be extremely fast beta particles, but their failure to be deflected by a magnetic field indicated that they had no charge. In 1914, gamma rays were observed to be reflected from crystal surfaces, Rutherford and his coworker Edward Andrade measured the wavelengths of gamma rays from radium, and found that they were similar to X-rays, but with shorter wavelengths and higher frequency. This was eventually recognized as giving them more energy per photon
Gamma ray
–
Gamma rays are emitted during
nuclear fission in nuclear explosions.
Gamma ray
–
Illustration of an emission of a gamma ray (γ) from an atomic nucleus
Gamma ray
Gamma ray
–
A
hypernova. Artist's illustration showing the life of a
massive star as
nuclear fusion converts lighter elements into heavier ones. When fusion no longer generates enough pressure to counteract gravity, the star rapidly collapses to form a
black hole. Theoretically, energy may be released during the collapse along the axis of rotation to form a long duration
gamma-ray burst.
41.
Radioactive contamination
–
Such contamination presents a hazard because of the radioactive decay of the contaminants, which emit harmful ionising radiation such as alpha particles or beta particles, gamma rays or neutrons. It is important to be clear that the contamination gives rise to the hazard. Contamination may affect a person, a place, an animal, a spilled vial of radioactive material like uranyl nitrate may contaminate the floor and any rags used to wipe up the spill. Radioactive contamination is typically the result of a spill or accident during the production, or use of, radionuclides, less typically, nuclear fallout is the distribution of radioactive contamination by a nuclear explosion. The amount of material released in an accident is called the source term. Contamination may occur from radioactive gases, liquids or particles, for example, if a radionuclide used in nuclear medicine is spilled, the material could be spread by people as they walk around. Radioactive contamination may also be a result of certain processes. In cases that radioactive material cannot be contained, it may be diluted to safe concentrations, for a discussion of environmental contamination by alpha emitters please see actinides in the environment. Contamination does not include residual radioactive material remaining at a site after the completion of decommissioning, therefore, radioactive material in sealed and designated containers is not properly referred to as contamination, although the units of measurement might be the same. Containment is the way of preventing contamination being released into the environment or coming into contact or being ingested by humans. Being within the intended Containment differentiates radioactive material from radioactive contamination, when radioactive materials are concentrated to a detectable level outside a containment, the area affected is generally referred to as contaminated. There are a number of techniques for containing radioactive material so that it does not spread beyond the containment. In the case of liquids this is by the use of high integrity tanks or containers, where material is likely to become airborne, then extensive use is made of the glovebox, which is a common technique in hazardous laboratory and process operations in many industries. A variety of radionuclides occur naturally in the environment, elements like uranium and thorium, and their decay products, are present in rock and soil. Potassium-40, a nuclide, makes up a small percentage of all potassium and is present in the human body. Other nuclides, like carbon-14, which is present in all living organisms, are created by cosmic rays. These levels of radioactivity pose little danger but can confuse measurement, a particular problem is encountered with naturally generated radon gas which can affect instruments which are set to detect contamination close to normal background levels and can cause false alarms. Because of this skill is required by the operator of radiological survey equipment to differentiate between background radiation and the radiation emanates from contamination
Radioactive contamination
–
The
Hanford site represents two-thirds of the United States'
high-level radioactive waste by volume.
Nuclear reactors line the riverbank at the Hanford Site along the
Columbia River in January 1960.
Radioactive contamination
–
As of 2013, the
Fukushima nuclear disaster site remains
highly radioactive, with some 160,000 evacuees still living in temporary housing, and some land will be unfarmable for centuries. The
difficult cleanup job will take 40 or more years, and cost tens of billions of dollars.
Radioactive contamination
–
Large industrial glovebox in the nuclear industry
Radioactive contamination
–
G-M counters being used as gamma survey monitors, seeking radioactive satellite debris
42.
Radioactive decay
–
A material containing such unstable nuclei is considered radioactive. Certain highly excited short-lived nuclear states can decay through neutron emission, or more rarely, however, for a collection of atoms, the collections expected decay rate is characterized in terms of their measured decay constants or half-lives. This is the basis of radiometric dating, the half-lives of radioactive atoms have no known upper limit, spanning a time range of over 55 orders of magnitude, from nearly instantaneous to far longer than the age of the universe. A radioactive nucleus with spin can have no defined orientation. If there are multiple particles produced during a single decay, as in decay, their relative angular distribution. Such a parent process could be a previous decay, or a nuclear reaction, the decaying nucleus is called the parent radionuclide, and the process produces at least one daughter nuclide. Except for gamma decay or internal conversion from an excited state. When the number of changes, an atom of a different chemical element is created. The first decay processes to be discovered were alpha decay, beta decay, alpha decay occurs when the nucleus ejects an alpha particle. This is the most common process of emitting nucleons, but highly excited nuclei can eject single nucleons, or in the case of cluster decay, specific light nuclei of other elements. Beta decay occurs when the nucleus emits an electron or positron, the nucleus may capture an orbiting electron, causing a proton to convert into a neutron in a process called electron capture. All of these result in a well-defined nuclear transmutation. By contrast, there are radioactive decay processes that do not result in a nuclear transmutation, another type of radioactive decay results in products that vary, appearing as two or more fragments of the original nucleus with a range of possible masses. For a summary table showing the number of stable and radioactive nuclides in each category, there are 29 naturally occurring chemical elements on Earth that are radioactive. They are those that contain 34 radionuclides that date before the time of formation of the solar system, well-known examples are uranium and thorium, but also included are naturally occurring long-lived radioisotopes, such as potassium-40. Radioactivity was discovered in 1896 by the French scientist Henri Becquerel and these materials glow in the dark after exposure to light, and he suspected that the glow produced in cathode ray tubes by X-rays might be associated with phosphorescence. He wrapped a photographic plate in black paper and placed various phosphorescent salts on it, all results were negative until he used uranium salts. The uranium salts caused a blackening of the plate in spite of the plate being wrapped in black paper and these radiations were given the name Becquerel Rays
Radioactive decay
–
Pierre and Marie Curie in their Paris laboratory, before 1907
Radioactive decay
–
Alpha decay is one type of radioactive decay, in which an atomic nucleus emits an
alpha particle, and thereby transforms (or "decays") into an atom with a
mass number decreased by 4 and
atomic number decreased by 2.
Radioactive decay
–
Taking an X-ray image with early
Crookes tube apparatus in 1896. The Crookes tube is visible in the centre. The standing man is viewing his hand with a
fluoroscope screen; this was a common way of setting up the tube. No precautions against radiation exposure are being taken; its hazards were not known at the time.
Radioactive decay
–
Gamma-ray energy spectrum of uranium ore (inset). Gamma-rays are emitted by decaying
nuclides, and the gamma-ray energy can be used to characterize the decay (which nuclide is decaying to which). Here, using the gamma-ray spectrum, several nuclides that are typical of the decay chain of 238 U have been identified: 226 Ra, 214 Pb, 214 Bi.
43.
Cheyenne Mountain nuclear bunker
–
Also located in Colorado Springs is Peterson Air Force Base, where the North American Aerospace Defense Command and United States Northern Command headquarters are located. The military complex has included, in the past, many units of NORAD, Space Command, Aerospace Defense Command, Air Force Systems Command, Air Weather Service, and Federal Emergency Management. The complexs communication center is used by the nearby U. S. Civil Defense Warning Center. The complex was built under 2,000 feet of granite on 2 hectares, a total of more than 1,000 springs are designed to prevent any of the 15 buildings from shifting more than one inch. The complex is the high altitude Department of Defense facility certified to be able to sustain an electromagnetic pulse. There is a quantity of cots for most of the personnel. Amenities include a facility, store, cafeteria, and fitness centers inside and outside the mountain. The bunker is built to deflect a 30 megaton nuclear explosion as close as 2 kilometers, within a mountain tunnel are sets of 25-ton blast doors and another for the civil engineering department. The doors were built so that they can always be opened when needed, should a nuclear blast hit the building, they are designed to withstand a blast wave. There is a network of blast valves with unique filters to capture air-borne chemical, biological, radiological, outside of the military complex are the parking lots, a heliport, a fire station, and outdoor recreational facilities. The recreational amenities include Mountain Man Park, picnic areas, a facility, softball field, sand volleyball court, basketball court, a putting green. A military gate limits NORAD Road usage from the State Highway 115 interchange, the least likely events are the most hazardous. There is more produced by mountain springs than the base needs. A reservoir of 4.5 million gallons of water is used as a heat sink, there is a massive reservoir for diesel fuel and a huge battery bank with redundant power generators. The North American Air Defense Command was established and activated at the Ent Air Force Base on September 12,1957 and this command is a bi-national organization, of Canadian and United States Air Defense Command units, in accordance with NORAD Agreements first made on May 12,1958. The Space Defense Center and the Combat Operations Center achieved full operational capability on February 6,1967, the total cost was $142.4 million. Its systems included a command and control system developed by Burroughs Corporation, the electronics and communications system centralized and automated the instantaneous evaluation of aerospace surveillance data. The Space Defense Center moved from Ent AFB to the complex in 1965, the NORAD Combat Operations Center was fully operational April 20,1966 and The Space Defense Commands 1st Aerospace Control Squadron moved to Cheyenne Mountain that month
Cheyenne Mountain nuclear bunker
–
Cheyenne Mountain Complex
Cheyenne Mountain nuclear bunker
–
The bunker's Command Center was upgraded 2003–4 for $13 million.
Cheyenne Mountain nuclear bunker
–
The 25-ton North
blast door is the main entrance to another blast door (background) beyond which the side tunnel branches into access tunnels to the main chambers.
Cheyenne Mountain nuclear bunker
–
The exterior North Portal protects the eastward tunnel opening. The south opening has a concrete abutment.
44.
Emergency Government Headquarters
–
Emergency Government Headquarters are nuclear fallout bunkers built by the Government of Canada at the height of the Cold War during the infancy of the ICBM threat. Over fifty bunkers were built, including the many redundant Relocation Unit locations as well as retrofitted buildings that comprised many Zone Emergency Government Headquarters locations, most of these facilities were built, often in great secrecy, at rural locations outside major cities across Canada. Each underground facility had entrances through massive blast doors at the surface, as well as air filters. Underground storage was built for food, fuel, fresh water, the largest Diefenbunker was located at CFS Carp in the village of Carp west of Ottawa, within the National Capital Region. In the event of an event, it was expected to shelter many of the most important federal civil servants and politicians. This location was the second chosen, the original location was approximately six miles west of Almonte at 45°15′7″N 76°19′32″W. That site was abandoned when ground water proved impossible to remove, there have been rumors that a tunnel leading to an alternate exit/entrance of the bunker was dug under the Ottawa River. This entrance was said to be in Pontiac or Aylmer, Quebec, however, this entrance was never discovered. CEGHQ Central Emergency Government Headquarters, located in Carp, Ontario, designed for use by senior federal politicians, civil servants, and monarchy. 45°21′8. 35″N 76°2′53. 61″W REGHQ Regional Emergency Government Headquarters, of which there were seven, each of these had a RU backup bunker. ZEGHQ Zone Emergency Government Headquarters, built within the basements of existing buildings, RU Relocation Unit, or CRU, Central Relocation Unit. Often bunkers built as redundant backups to REGHQs and MEGHQs were given the RU designation, similar sites were chosen to accompany the REGHQs elsewhere in Canada. These would be located in proximity to the REGHQs. These Regional Relocation Units would be used as a backup to the larger equivalent Other bunkers in Ontario included Central Relocation Units to supplement the CEGHQ. These were not true bunkers for the fact that they were simply reinforced underground rooms located in basements of post offices and they were connected by phone and teletypewriter lines to the main bunker at CFS Carp. Douglas Stewart, head engineer for the Canadian National Defence, was key to the design, following the end of the Cold War, most of the Diefenbunkers were decommissioned. Several of the facilities on active Canadian Forces Bases, such as CFB Borden and CFB Valcartier, Diefenbunkers located on smaller Canadian Forces Stations were mostly sold off or demolished. The only Diefenbunker which members of the public may visit is the one at former CFS Carp, however, the Canadian military cleared out the bunker as it was decommissioned, so the museum has had to try to reacquire the original furnishings that were disposed of
Emergency Government Headquarters
–
Conference room at the
CFS Carp bunker, 30 km west of
Ottawa
Emergency Government Headquarters
–
Teletype Corp Model 40 Terminals at the CEGHQ,
CFS Carp
45.
Placard
–
A placard is a notice installed in a public place, like a small card, sign, or plaque. It can be attached to or hung from a vehicle or building to indicate information about the operator or contents of a vehicle or building. It can also refer to paperboard signs or notice carried by picketers or demonstrators, a placard is placed on a building to indicate special information about that building. Temporary placards may be placed on such as warning signs over tenting to indicate the building is being fumigated. The two most common placards in general use on vehicles are disabled parking permits for personal automobiles, there are other types, such as the wide load signs used when mobile homes are transported by road. To see the signs put on trucks and trains meaning hazmats see, in computer graphical user interfaces, a placard is a rectangular area of a window meant for displaying information to the user. In Model United Nations, the nameplate of a delegation is referred to as a placard. Affair of the Placards,17 October 1534 anti-Catholic incident where posters appeared in places in five major French cities which brought an end to the conciliatory policies of King Francis I. Election placard Poster The dictionary definition of placard at Wiktionary Media related to Placards at Wikimedia Commons
Placard
–
Old fallout shelter sign
Placard
–
European type hazard sign, saying highly
inflammable (33) -
gasoline (1203)
46.
Trefoil
–
Trefoil is a graphic form composed of the outline of three overlapping rings used in architecture and Christian symbolism. The term is applied to other symbols of three-fold shape. One of the earliest examples is in the tracery at Winchester. The fourfold version of an architectural trefoil is a quatrefoil, two forms of this are shown below, A dove, symbolic of the Holy Spirit, is sometimes depicted within the outlined form of the trefoil combined with a triangle. In architecture and archaeology, trefoil describes a layout or floorplan consisting of three apses in clover-leaf shape, as for example in the Megalithic temples of Malta, particularly in church architecture, such a layout may be called a triconchos. The heraldic trefoil is a stylized clover and it should not be confused with the figure named in French heraldry tiercefeuille, which is a stylized flower with three petals. It differs from the heraldic trefoil in being not slipped and it could be translated as threefoil. Symmetrical Trefoils are particularly popular as warning and informational symbols, easily stenciled symbols are also favored. While the green trefoil is considered by many to be the symbol of Ireland, therefore, shamrocks generally do not appear on Irish coins or postage stamps. A trefoil is also part of the logo for Adidas Originals, a trefoil formation is a cross-sectional arrangement of electrical cables that minimises electrodynamic forces during fault conditions. Also, the field of each phase conductor in a 3-phase system is negated when the other two phase conductors are nearby to form a trefoil. Fleur-de-Lys Foil Trefoil domain Trefoil arch Trefoil knot Torus knot Quatrefoil Explanation of Christian symbolism of Trefoil
Trefoil
–
Evolution of layout of Maltese Megalithic temples; Skorba (upper right) has a typical trefoil plan
Trefoil
–
Architectural trefoil
47.
National Emergency Alarm Repeater
–
The National Emergency Alarm Repeater was a civilian emergency warning device in the United States. It was a 2–3 square box designed to plug into a power outlet to receive a special signal sent over the electric power transmission lines. Research and testing for the NEAR program was developed in 1956 during the Cold War to supplement the existing siren warning systems, despite this advantage, upon the introduction of the Emergency Broadcast system, the stockpiled NEAR repeaters were destroyed by their respective manufacturers. A similar program was proposed in the United Kingdom during the 1960s, the device is a buzzer installed into ordinary electrical outlets. The devices would be set off in an emergency by altering the regular AC signal being generated and transmitted by the power companies. The indoor buzzers would be supplemented with outdoor warning sirens, EMP effects of a high-altitude nuclear could have disabled the system. After a decade of support for testing and development, the program was terminated. Status of NEAR program still cloudy to utilities, III, Warning Systems, Federal Warning Systems, page 9. Gilbert, Wayne The Cold War Artifact that NEAR-ly Changed My Life Denverpost. com Nuclear Survival Manual,1963, www. archive. org Original Patent document, US3,284,791, of one type of NEAR receiver
National Emergency Alarm Repeater
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The N.E.A.R. Warning Device.
National Emergency Alarm Repeater
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The
mushroom cloud of the
atomic bombing of Nagasaki, Japan in 1945 rose some 18 kilometers (11 miles) above the bomb's
hypocenter.
National Emergency Alarm Repeater
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Civil Defense logo on a Thunderbolt 1003 siren.
48.
Nuclear attack
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Nuclear warfare is a military conflict or political strategy in which nuclear weaponry is used to inflict damage on the enemy. In contrast to conventional warfare, nuclear warfare can produce destruction in a much shorter time-frame, some activists had claimed in the 1980s that with this potential nuclear winter side-effect of a nuclear war, almost every human on Earth could starve to death. 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 was detonated over the Japanese city of Hiroshima. Three days later, on August 9, a plutonium device was detonated over the Japanese city of Nagasaki. These two bombings resulted in the deaths of approximately 120,000 people, in 1974, India, and in 1998, Pakistan, two countries that were openly hostile toward each other, developed nuclear weapons. Israel and North Korea are also thought to have developed stocks of nuclear weapons, the Israeli government has never admitted to having nuclear weapons, although it is known to have constructed the reactor and reprocessing plant necessary for building nuclear weapons. Nuclear weapons have been detonated on over 2,000 occasions for testing purposes, after the collapse of the Soviet Union in 1991 and the resultant end of the Cold War, the threat of a major nuclear war between the two nuclear superpowers was generally thought to have declined. Since then, concern over nuclear weapons has shifted to the prevention of localized nuclear conflicts resulting from nuclear proliferation, the possibility of using nuclear weapons in war is usually divided into two subgroups, each with different effects and potentially fought with different types of nuclear armaments. The first, a nuclear war, refers to a small-scale use of nuclear weapons by two belligerents. This term could apply to any use of nuclear weapons that may involve military or civilian targets. The second, a nuclear war, could consist of large numbers of nuclear weapons used in an attack aimed at an entire country, including military, economic. Such an attack would almost certainly destroy the economic, social, and military infrastructure of the target nation. Some Cold War strategists such as Henry Kissinger argued that a nuclear war could be possible between two heavily armed superpowers. Some predict, however, that a war could potentially escalate into a full-scale nuclear war. Even the most optimistic predictions of the effects of a nuclear exchange foresee the death of many millions of victims within a very short period of time. However, such predictions, assuming total war with nuclear arsenals at Cold War highs, have not been without criticism. The authors of the study estimated that as much as five tons of soot could be released, producing a cooling of several degrees over large areas of North America. The cooling would last for years and could be catastrophic, according to the researchers, either a limited or full-scale nuclear exchange could occur during an accidental nuclear war, in which the use of nuclear weapons is triggered unintentionally
Nuclear attack
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Nuclear weapons
Nuclear attack
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The
Titan II Intercontinental ballistic missile (ICBM) carried a 9
Mt W53 warhead, one of the most powerful
nuclear weapons fielded by the
United States during the
Cold War.
Nuclear attack
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Mushroom cloud from the atomic explosion over Nagasaki rising 18,000 m (59,000 ft) into the air on the morning of August 9, 1945.
Nuclear attack
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Convair B-36 bomber
49.
John F. Kennedy
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Kennedy was a member of the Democratic Party, and his New Frontier domestic program was largely enacted as a memorial to him after his death. Kennedy also established the Presidential Medal of Freedom in 1963, Kennedys time in office was marked by high tensions with Communist states. He increased the number of American military advisers in South Vietnam by a factor of 18 over President Dwight D. Eisenhower, in Cuba, a failed attempt was made at the Bay of Pigs to overthrow the government of Fidel Castro in April 1961. He subsequently rejected plans by the Joint Chiefs of Staff to orchestrate false-flag attacks on American soil in order to gain approval for a war against Cuba. After military service in the United States Naval Reserve in World War II and he was elected subsequently to the U. S. Senate and served as the junior Senator from Massachusetts from 1953 until 1960. Kennedy defeated Vice President, and Republican presidential candidate, Richard Nixon in the 1960 U. S, at age 43, he became the youngest elected president and the second-youngest president. Kennedy was also the first person born in the 20th century to serve as president, to date, Kennedy has been the only Roman Catholic president and the only president to have won a Pulitzer Prize. Kennedy was assassinated in Dallas, Texas, on November 22,1963, Lee Harvey Oswald was arrested that afternoon and determined to have fired the shots that hit the President from a sixth floor window of the Texas School Book Depository. Dallas nightclub owner Jack Ruby fatally shot Oswald two days later in a jail corridor, then-Vice President Lyndon B. Johnson succeeded Kennedy after he died in the hospital. The FBI and the Warren Commission officially concluded that Oswald was the lone assassin, the majority of Americans alive at the time of the assassination, and continuing through 2013, believed that there was a conspiracy and that Oswald was not the only shooter. Since the 1960s, information concerning Kennedys private life has come to light, including his health problems, Kennedy continues to rank highly in historians polls of U. S. presidents and with the general public. His average approval rating of 70% is the highest of any president in Gallups history of systematically measuring job approval and his grandfathers P. J. Kennedy and Boston Mayor John F. Fitzgerald were both Massachusetts politicians. All four of his grandparents were the children of Irish immigrants, Kennedy had an elder brother, Joseph Jr. and seven younger siblings, Rosemary, Kathleen, Eunice, Patricia, Robert, Jean, and Ted. Kennedy lived in Brookline for ten years and attended the Edward Devotion School, the Noble and Greenough Lower School, and the Dexter School through 4th grade. In 1927, the Kennedy family moved to a stately twenty-room, Georgian-style mansion at 5040 Independence Avenue in the Hudson Hill neighborhood of Riverdale, Bronx and he attended the lower campus of Riverdale Country School, a private school for boys, from 5th to 7th grade. Two years later, the moved to 294 Pondfield Road in the New York City suburb of Bronxville, New York. The Kennedy family spent summers at their home in Hyannis Port, Massachusetts, in September 1930, Kennedy—then 13 years old—attended the Canterbury School in New Milford, Connecticut. In late April 1931, he required an appendectomy, after which he withdrew from Canterbury, in September 1931, Kennedy attended Choate, a boarding school in Wallingford, Connecticut, for 9th through 12th grade
John F. Kennedy
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John F. Kennedy
John F. Kennedy
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The Kennedy family at
Hyannis Port, Massachusetts, in 1931 with Jack at top left in white shirt. Ted was born the following year.
John F. Kennedy
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Lieutenant (junior grade) John F. Kennedy (standing at right) with his PT-109 crew, 1943.
John F. Kennedy
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Kennedy on his navy patrol boat, the
PT-109, 1943.
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