1.
Underground nuclear weapons testing
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Underground nuclear testing is the test detonation of nuclear weapons that is performed underground. When the device being tested is buried at sufficient depth, the explosion may be contained, the extreme heat and pressure of an underground nuclear explosion causes changes in the surrounding rock. The rock closest to the location of the test is vaporised, farther away, there are zones of crushed, cracked, and irreversibly strained rock. Following the explosion, the rock above the cavity may collapse, if this chimney reaches the surface, a bowl-shaped subsidence crater may form. From then until the signing of the Comprehensive Test Ban Treaty in 1996, most nuclear tests were performed underground, although public concern about fallout from nuclear testing grew in the early 1950s, fallout was discovered after the Trinity test in 1945. Intense fallout from the 1953 Simon test was documented as far as Albany, the fallout from the March 1954 Bravo test in the Pacific would have scientific, political and social implications that have continued for more than 40 years. The multi-megaton test caused fallout to occur on the islands of the Rongerik and Rongelap atolls, prior to this test, there was insufficient appreciation of the dangers of fallout. The test became an international incident and it becomes a big issue in the media. Theyre very concerned about, first of all, why the United States even has the right to be carrying out those kinds of tests in the Pacific, theyre also concerned about the health and environmental impact. The Prime Minister of India voiced the heightened international concern when he called for the elimination of all nuclear testing worldwide, knowledge about fallout and its effects grew, and with it concern about the global environment and long-term genetic damage. Talks between the United States, the United Kingdom, Canada, France, and the Soviet Union began in May 1955 on the subject of an agreement to end nuclear tests. Agreement was facilitated by the decision to allow underground testing, eliminating the need for on-site inspections that concerned the Soviets, following analysis of underwater detonations that were part of Operation Crossroads in 1946, inquiries were made regarding the possible military value of an underground explosion. The Joint Chiefs of Staff thus obtained the agreement of the Atomic Energy Commission to perform experiments on both surface and sub-surface detonations. The island of Amchitka was initially selected for tests in 1950, but the site was later deemed unsuitable. The first underground nuclear test was conducted on 29 November 1951 and this was the 1.2 kiloton Buster-Jangle Uncle, which detonated 5.2 m beneath ground level. The test was designed as an investigation of the effects of a 23 kiloton ground penetrating gun-type device that was then being considered for use as a cratering. The explosion resulted in a cloud that rose to 3,500 m, the resulting crater was 79 m wide and 16 m deep. The next underground test was Teapot Ess, on 23 March 1955, the 1 kiloton explosion was an operational test of an atomic demolition munition
2.
Soviet Union
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The Soviet Union, officially the Union of Soviet Socialist Republics was a socialist state in Eurasia that existed from 1922 to 1991. It was nominally a union of national republics, but its government. The Soviet Union had its roots in the October Revolution of 1917 and this established the Russian Socialist Federative Soviet Republic and started the Russian Civil War between the revolutionary Reds and the counter-revolutionary Whites. In 1922, the communists were victorious, forming the Soviet Union with the unification of the Russian, Transcaucasian, Ukrainian, following Lenins death in 1924, a collective leadership and a brief power struggle, Joseph Stalin came to power in the mid-1920s. Stalin suppressed all opposition to his rule, committed the state ideology to Marxism–Leninism. As a result, the country underwent a period of rapid industrialization and collectivization which laid the foundation for its victory in World War II and postwar dominance of Eastern Europe. Shortly before World War II, Stalin signed the Molotov–Ribbentrop Pact agreeing to non-aggression with Nazi Germany, in June 1941, the Germans invaded the Soviet Union, opening the largest and bloodiest theater of war in history. Soviet war casualties accounted for the highest proportion of the conflict in the effort of acquiring the upper hand over Axis forces at battles such as Stalingrad. Soviet forces eventually captured Berlin in 1945, the territory overtaken by the Red Army became satellite states of the Eastern Bloc. The Cold War emerged by 1947 as the Soviet bloc confronted the Western states that united in the North Atlantic Treaty Organization in 1949. Following Stalins death in 1953, a period of political and economic liberalization, known as de-Stalinization and Khrushchevs Thaw, the country developed rapidly, as millions of peasants were moved into industrialized cities. The USSR took a lead in the Space Race with Sputnik 1, the first ever satellite, and Vostok 1. In the 1970s, there was a brief détente of relations with the United States, the war drained economic resources and was matched by an escalation of American military aid to Mujahideen fighters. In the mid-1980s, the last Soviet leader, Mikhail Gorbachev, sought to reform and liberalize the economy through his policies of glasnost. The goal was to preserve the Communist Party while reversing the economic stagnation, the Cold War ended during his tenure, and in 1989 Soviet satellite countries in Eastern Europe overthrew their respective communist regimes. This led to the rise of strong nationalist and separatist movements inside the USSR as well, in August 1991, a coup détat was attempted by Communist Party hardliners. It failed, with Russian President Boris Yeltsin playing a role in facing down the coup. On 25 December 1991, Gorbachev resigned and the twelve constituent republics emerged from the dissolution of the Soviet Union as independent post-Soviet states
3.
Peaceful nuclear explosion
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Peaceful nuclear explosions are nuclear explosions conducted for non-military purposes, such as activities related to economic development including the creation of canals. During the 1960s and 1970s, both the United States and the Soviet Union conducted a number of PNEs, six of the explosions by the Soviet Union are considered to have been of an applied nature, not just tests. Subsequently the United States and the Soviet Union halted their programs, definitions and limits are covered in the Peaceful Nuclear Explosions Treaty of 1976. The Comprehensive Nuclear-Test-Ban Treaty of 1996 prohibits all nuclear explosions, regardless of whether they are for purposes or not. The parties also reaffirmed their obligations to comply fully with the Limited Test Ban Treaty of 1963, articles IV and V of the PNE Treaty set forth the agreed verification arrangements. The agreed statement that accompanies the treaty specifies that an application of an underground nuclear explosion would not include the developmental testing of any nuclear explosive. Operation Plowshare was the name of the U. S. program for the development of techniques to use explosives for peaceful purposes. The name was coined in 1961, taken from Micah 4,3, twenty-eight nuclear blasts were detonated between 1961 and 1973. It was never carried out due to concerns for the native populations, there was also talk of using nuclear explosions to excavate a second Panama Canal. The largest excavation experiment took place in 1962 at the Department of Energys Nevada Test Site, three tests were conducted in order to stimulate natural gas production, but the effort was abandoned as impractical because of cost and radioactive contamination of the gas. There were many negative impacts from Project Plowshare’s 27 nuclear explosions, for example, the Gasbuggy site, located 55 miles east of Farmington, New Mexico, still contains nuclear contamination from a single subsurface blast in 1967. Other consequences included blighted land, relocated communities, tritium-contaminated water, radioactivity and these were ignored and downplayed until the program was terminated in 1977, due in large part to public opposition, after $770 million had been spent on the project. Its aims and results were similar to those of the American effort, with the exception that many of the blasts were considered applications, not tests. The best known of these in the West was the Chagan test in January 1965 as radioactivity from the Chagan test was detected over Japan by both the U. S. and Japan, the United States complained to the Soviets, but the matter was dropped. In the 1970s, the Soviet Union started the Deep Seismic Sounding Program, compared to the usage of conventional explosives or mechanical methods, nuclear explosions allow the collection of longer seismic profiles. There are proponents for continuing the PNE programs in modern Russia and they state that the program already paid for itself and saved the USSR billions of rubles and can save even more if continued. They also allege that the PNE is the only way to put out large fountains and fires on natural gas deposits. Their opponents, including the discredited Alexey Yablokov, state that all PNE technologies have non-nuclear alternatives, germany at one time considered manufacturing nuclear explosives for civil engineering purposes
4.
TNT
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Trinitrotoluene, or more specifically 2,4, 6-trinitrotoluene, is a chemical compound with the formula C6H23CH3. This yellow-colored solid is used as a reagent in chemical synthesis. The explosive yield of TNT is considered to be the measure of bombs. In chemistry, TNT is used to charge transfer salts. TNT was first prepared in 1863 by German chemist Julius Wilbrand and its potential as an explosive was not appreciated for several years, mainly because it was so difficult to detonate and because it was less powerful than alternatives. Its explosive properties were first discovered by another German chemist, Carl Häussermann, the German armed forces adopted it as a filling for artillery shells in 1902. The British started replacing lyddite with TNT in 1907, TNT is still widely used by the United States military, as well as construction companies around the world. The majority of TNT currently used by the US military is manufactured by Radford Army Ammunition Plant near Radford, in industry, TNT is produced in a three-step process. First, toluene is nitrated with a mixture of sulfuric and nitric acid to produce mononitrotoluene, the MNT is separated and then renitrated to dinitrotoluene. In the final step, the DNT is nitrated to trinitrotoluene using a mixture of nitric acid. Nitric acid is consumed by the process, but the diluted sulfuric acid can be reconcentrated and reused. The rinse water from sulphitation is known as red water and is a significant pollutant, control of nitrogen oxides in feed nitric acid is very important because free nitrogen dioxide can result in oxidation of the methyl group of toluene. This reaction is exothermic and carries with it the risk of a runaway reaction leading to an explosion. In the laboratory,2,4, 6-trinitrotoluene is produced by a two-step process, a nitrating mixture of concentrated nitric and sulfuric acids is used to nitrate toluene to a mixture of mono- and di-nitrotoluene isomers, with careful cooling to maintain temperature. The nitrated toluenes are then separated, washed with dilute sodium bicarbonate to remove oxides of nitrogen, towards the end of the nitration, the mixture is heated on a steam bath. The trinitrotoluene is separated, washed with a solution of sodium sulfite. TNT is one of the most commonly used explosives for military, industrial, TNT has been used in conjunction with hydraulic fracturing, a process used to recover oil and gas from shale formations. The technique involves displacing and detonating nitroglycerin in hydraulically induced fractures followed by wellbore shots using pelletized TNT, TNT is valued partly because of its insensitivity to shock and friction, with reduced risk of accidental detonation compared to more sensitive explosives such as nitroglycerin
5.
Lake
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A lake is an area of variable size filled with water, localized in a basin, that is surrounded by land, apart from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, and therefore are distinct from lagoons, Lakes can be contrasted with rivers or streams, which are usually flowing. Most lakes are fed and drained by rivers and streams, natural lakes are generally found in mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers, in some parts of the world there are many lakes because of chaotic drainage patterns left over from the last Ice Age. All lakes are temporary over geologic time scales, as they will fill in with sediments or spill out of the basin containing them. The word lake comes from Middle English lake, from Old English lacu, from Proto-Germanic *lakō, cognates include Dutch laak, Middle Low German lāke as in, de, Moorlake, de, Wolfslake, de, Butterlake, German Lache, and Icelandic lækur. Also related are the English words leak and leach, none of these definitions completely excludes ponds and all are difficult to measure. For this reason, simple size-based definitions are used to separate ponds. One definition of lake is a body of water of 2 hectares or more in area, however, others have defined lakes as waterbodies of 5 hectares and above, or 8 hectares and above. Charles Elton, one of the founders of ecology, regarded lakes as waterbodies of 40 hectares or more. The term lake is used to describe a feature such as Lake Eyre. In common usage, many bear names ending with the word pond. One textbook illustrates this point with the following, In Newfoundland, for example, almost every lake is called a pond, whereas in Wisconsin, the majority of lakes on Earth are fresh water, and most lie in the Northern Hemisphere at higher latitudes. Canada, with a drainage system has an estimated 31,752 lakes larger than 3 square kilometres and an unknown total number of lakes. Finland has 187,888 lakes 500 square metres or larger, most lakes have at least one natural outflow in the form of a river or stream, which maintain a lakes average level by allowing the drainage of excess water. Some lakes do not have an outflow and lose water solely by evaporation or underground seepage or both. Many lakes are artificial and are constructed for power generation, aesthetic purposes, recreational purposes, industrial use. Globally, lakes are greatly outnumbered by ponds, of an estimated 304 million standing water bodies worldwide, 91% are 1 hectare or less in area
6.
Partial Nuclear Test Ban Treaty
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The impetus for the test ban was provided by rising public anxiety over the magnitude of nuclear tests, particularly tests of new thermonuclear weapons, and the resulting nuclear fallout. A test ban was also seen as a means of slowing nuclear proliferation, though the PTBT did not halt proliferation or the arms race, its enactment did coincide with a substantial decline in the concentration of radioactive particles in the atmosphere. The PTBT was signed by the governments of the Soviet Union, United Kingdom, the treaty formally went into effect on 10 October 1963. Since then,123 other states have become party to the treaty, ten states have signed but not ratified the treaty. In 1952–53, the US and Soviet Union detonated their first thermonuclear weapons, in 1954, the US Castle Bravo test at Bikini Atoll had a yield of 15 megatons of TNT, more than doubling the expected yield. In the same year, a Soviet test sent radioactive particles over Japan, around the same time, victims of the atomic bombing of Hiroshima visited the US for medical care, which attracted significant public attention. Between 1951 and 1958, the US conducted 166 atmospheric tests, the Soviet Union conducted 82, in 1945, Britain and Canada made an early call for an international discussion on controlling atomic power. At the time, the US had yet to formulate a policy or strategy on nuclear weapons. Taking advantage of this was Vannevar Bush, who had initiated and administered the Manhattan Project, as a first step in this direction, Bush proposed an international agency dedicated to nuclear control. Truman to help construct US nuclear weapons policy, a version of the Acheson-Lilienthal plan was presented to the United Nations Atomic Energy Commission as the Baruch Plan in June 1946. The Baruch Plan proposed that an International Atomic Development Authority would control all research on and material, the Soviet Union dismissed the Baruch Plan as a US attempt to secure its nuclear dominance, and called for the US to halt weapons production and release technical information on its program. The Acheson–Lilienthal paper and Baruch Plan would serve as the basis for US policy into the 1950s, between 1947 and 1954, the US and Soviet Union discussed their demands within the United Nations Commission for Conventional Disarmament. A series of events in 1954, including the Castle Bravo test and spread of fallout from a Soviet test over Japan, additionally, by 1954, both US and Soviet Union had assembled large nuclear stockpiles, reducing hopes of complete disarmament. Interest in nuclear control and efforts to stall proliferation of weapons to other states grew as the Soviet Unions nuclear capabilities increased, in the same year, the British Labour Party, then led by Clement Attlee, called on the UN to ban testing of thermonuclear weapons. 1955 marks the beginning of negotiations, as Soviet leader Nikita Khrushchev first proposed talks on the subject in February 1955. On 10 May 1955, the Soviet Union proposed a test ban before the UN Disarmament Commissions Committee of Five, the May 1955 proposal is now seen evidence of Khrushchevs new approach to foreign policy, as Khrushchev sought to mend relations with the West. The proposal would serve as the basis of the Soviet negotiating position through 1957, Eisenhower had supported nuclear testing after World War II. In 1947, he rejected arguments by Stafford L. Warrens arguments were lent credence in the scientific community, everybody seems to think that were skunks, saber-rattlers and warmongers
7.
Mushroom cloud
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A mushroom cloud is a distinctive pyrocumulus mushroom-shaped cloud of debris/smoke and usually condensed water vapor resulting from a large explosion. The effect is most commonly associated with an explosion. They can be caused by conventional weapons, like vacuum bombs, including the ATBIP. Some volcanic eruptions and impact events can produce natural mushroom clouds, mushroom clouds result from the sudden formation of a large volume of lower-density gases at any altitude, causing a Rayleigh–Taylor instability. The stabilization altitude depends strongly on the profiles of the temperature, dew point, although the term appears to have been coined at the start of the 1950s, mushroom clouds generated by explosions were being described centuries before the atomic era. The Times published a report on 1 October 1937 of a Japanese attack on Shanghai in China which generated a great mushroom of smoke, the 1917 Halifax Explosion also produced one. During World War II, descriptions of mushroom clouds were relatively common, the atomic bomb cloud over Nagasaki, Japan was described in The Times of London of 13 August 1945 as a huge mushroom of smoke and dust. He wrote of the bomb producing a pillar of purple fire, later in 1946, the Operation Crossroads nuclear bomb tests were described as having a cauliflower cloud, but a reporter present also spoke of the mushroom, now the common symbol of the atomic age. Mushrooms have traditionally been associated both with life and death, food and poison, making them a powerful symbolic connection than, say. Mushroom clouds are formed by many sorts of large explosions under earths gravity, without gravity, the explosives by-product gases would remain spherical. Nuclear weapons are usually detonated above the ground, to maximize the effect of their spherically expanding fireball, immediately after the detonation, the fireball begins to rise into the air, acting on the same principle as a hot-air balloon. One way to analyze the motion, once the hot gas has cleared the ground sufficiently, is as a spherical cap bubble, as this gives agreement between the rate of rise and observed diameter. When the detonation altitude is low enough, these afterwinds will draw in dirt, Nuclear detonations produced high above the ground might not create mushroom clouds with a stem. Detonations underwater but near the surface produce a pillar of water, which, in collapsing, forms a cauliflower-like shape, underground detonations at low depth produce a mushroom cloud and a base surge, two different distinct clouds. The amount of radiation vented into the atmosphere decreases rapidly with increasing detonation depth, with surface and near-surface air bursts, the amount of debris lofted into the air decreases rapidly with increasing burst altitude. At burst altitudes of approximately 7 meters/kiloton^0.33, a crater is not formed, the fallout-reducing height, above which the primary radioactive particles consist mainly of the fine fireball condensation, is approximately 55 meters/kiloton^0.4. However, even at these burst altitudes, fallout may be formed by a number of mechanisms, the distribution of radiation in the mushroom cloud varies with yield of the explosion, type of weapon, fusion/fission ratio, burst altitude, terrain type, and weather. In general, lower-yield explosions have about 90% of their radioactivity in the mushroom head, in contrast, megaton-range explosions tend to have most of their radioactivity in the lower third of the mushroom cloud
8.
Kazakhstan
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Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country in northern Central Asia and Eastern Europe. Kazakhstan is the worlds largest landlocked country, and the ninth largest in the world, Kazakhstan is the dominant nation of Central Asia economically, generating 60% of the regions GDP, primarily through its oil/gas industry. It also has vast mineral resources, Kazakhstan is officially a democratic, secular, unitary, constitutional republic with a diverse cultural heritage. Kazakhstan shares borders with Russia, China, Kyrgyzstan, Uzbekistan, and Turkmenistan, the terrain of Kazakhstan includes flatlands, steppe, taiga, rock canyons, hills, deltas, snow-capped mountains, and deserts. Kazakhstan has an estimated 18 million people as of 2014, Given its large area, its population density is among the lowest. The capital is Astana, where it was moved in 1997 from Almaty, the territory of Kazakhstan has historically been inhabited by nomadic tribes. This changed in the 13th century, when Genghis Khan occupied the country as part of the Mongolian Empire, following internal struggles among the conquerors, power eventually reverted to the nomads. By the 16th century, the Kazakh emerged as a distinct group, the Russians began advancing into the Kazakh steppe in the 18th century, and by the mid-19th century, they nominally ruled all of Kazakhstan as part of the Russian Empire. Following the 1917 Russian Revolution, and subsequent civil war, the territory of Kazakhstan was reorganised several times, in 1936, it was made the Kazakh Soviet Socialist Republic, part of the Soviet Union. Kazakhstan was the last of the Soviet republics to declare independence during the dissolution of the Soviet Union in 1991, Kazakhstan has worked to develop its economy, especially its dominant hydrocarbon industry. Kazakhstans 131 ethnicities include Kazakhs, Russians, Uzbeks, Ukrainians, Germans, Tatars, the Kazakh language is the state language, and Russian has equal official status for all levels of administrative and institutional purposes. The name Kazakh comes from the ancient Turkic word qaz, to wander, the name Cossack is of the same origin. The Persian suffix -stan means land or place of, so Kazakhstan can be translated as land of the wanderers. Kazakhstan has been inhabited since the Neolithic Age, the regions climate, archaeologists believe that humans first domesticated the horse in the regions vast steppes. Central Asia was originally inhabited by the Scythians, the Cuman entered the steppes of modern-day Kazakhstan around the early 11th century, where they later joined with the Kipchak and established the vast Cuman-Kipchak confederation. Under the Mongol Empire, the largest in history, administrative districts were established. These eventually came under the rule of the emergent Kazakh Khanate, throughout this period, traditional nomadic life and a livestock-based economy continued to dominate the steppe. Nevertheless, the region was the focus of ever-increasing disputes between the native Kazakh emirs and the neighbouring Persian-speaking peoples to the south, at its height the Khanate would rule parts of Central Asia and control Cumania
9.
Alamogordo, New Mexico
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Alamogordo /ˌæləməˈɡɔːrdoʊ/ is the seat of Otero County, New Mexico, United States. A city in the Tularosa Basin of the Chihuahuan Desert, it is bordered on the east by the Sacramento Mountains and it is the city nearest to Holloman Air Force Base. The population was 30,403 as of the 2010 census, Alamogordo is known for its connection with the Trinity test, the first explosion of an atomic bomb, and also for the Atari video game burial of 1983. Humans have lived in the Alamogordo area for at least 11,000 years, the present settlement, established in 1898 to support the construction of the El Paso and Northeastern Railroad, is an early example of a planned community. The city was incorporated in 1912, tourism became an important economic factor with the creation of White Sands National Monument in 1934. During the 1950-60s, Alamogordo was a center for research on pilot safety. Alamogordo is a city with a council-manager form of government. Gerald Champion Regional Medical Center is a nonprofit shared military/civilian facility that is also the hospital for Holloman, Tularosa Basin has been inhabited for at least 11,000 years. There are signs of inhabitants in the area such as the Clovis culture, the Folsom culture, the peoples of the Archaic period. The Mescalero Apache were already living in the Tularosa Basin when the Spanish came in 1534, the Spanish built a chapel at La Luz in 1719, although La Luz was not settled until about 1860. The city of Alamogordo was founded in June 1898, when the El Paso and Northeastern Railroad, headed by Charles Bishop Eddy, Eddy influenced the design of the community, which included large wide thoroughfares and tree-lined irrigation canals. Charles Eddys brother John Arthur Eddy named the new city Alamogordo after a grove of fat cottonwoods he remembered from the Pecos River area, when Alamogordo was laid out in 1898, the east-west streets were given numerical designations, while north-south streets were named after states. The present-day White Sands Boulevard was then called Pennsylvania Avenue, several government buildings in Alamogordo were constructed by the Works Progress Administration, a government program created in 1935 in response to the Great Depression. These include the Otero County Administration Building at 1101 New York Avenue, the building is listed in the National Register of Historic Places. The main entrance portico features frescoes by Peter Hurd completed in 1942, the Post Office moved out in 1961, and the building was used by a succession of Federal agencies and was known as the Federal Building. Ownership of the building was transferred to Otero County government and many government offices were moved from the Courthouse to the new Administration Building in February 2009. Alamogordo briefly made news in late 2001 when Christ Community Church held a public book burning of books in the Harry Potter series. As of 2010, Alamogordo had an area of 19.3 square miles
10.
Radioactive decay
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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
11.
Sedan (nuclear test)
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The radioactive fallout from the test contaminated more US residents than any other nuclear test. The Sedan Crater is the largest man-made crater in the United States, Sedan was a thermonuclear device with a fission yield less than 30% and a fusion yield about 70%. The device had a diameter of 43 cm, length of 96.5 cm, the explosive device was lowered into a shaft drilled into the desert alluvium 194 m deep. The resulting crater is 100 m deep with a diameter of about 390 m, a circular area of the desert floor five miles across was obscured by fast-expanding dust clouds moving out horizontally from the base surge, akin to pyroclastic surge. The blast caused seismic waves equivalent to an earthquake of 4.75 on the Richter scale, the radiation level on the crater lip at 1 hour after burst was 500 R per hour, but it dropped to 500 mR per hour after 27 days. Within 7 months of the excavation, the bottom of the crater could be walked upon with no protective clothing. The Sedan shot resulted in a cloud that separated into two plumes, rising to 3.0 km and 4.9 km. The two plumes headed northeast and then east in parallel paths towards the Atlantic Ocean. Nuclear fallout was dropped along the way, narrowly dispersed in a small number of United States counties. Detected radioactivity was especially high in eight counties in Iowa and one county each in Nebraska, South Dakota and these four counties measured maximum levels higher than 6,000 microcuries per square meter. Of all the tests conducted in the USA, Sedan ranked highest in overall activity of radionuclides in fallout. The test released 880,000 curies of radioactive iodine-131, an agent of thyroid disease, Sedan ranked first in percentages of these particular radionuclides detected in fallout, 198Au, 199Au, 7Be, 99Mo, 147Nd, 203Pb, 181W, 185W and 188W. Sedan ranked second in these radionuclides in fallout, 57Co, 60Co, Sedan ranked third in the detected amount of 24Na in fallout. In countrywide deposition of radionuclides, Sedan was highest in the amount of 7Be, 54Mn, 106Ru and 242Cm, and second highest in the amount of deposited 127mTe. Although not detected in fallout, in part because the explosion was contained, gold was used in the W71 warhead. Sedans fallout contamination contributed a little under 7% to the amount of radiation which fell on the U. S. population during all of the nuclear tests at NTS. Sedans effects were similar to shot George of Operation Tumbler-Snapper, detonated on June 1,1952, if this test was conducted in 1965+, when improvements in device design were realized, a 100-fold reduction in radiation release was considered feasible. The Plowshare project developed the Sedan test in order to determine the feasibility of using nuclear detonations to quickly and economically excavate large amounts of earth and rock
12.
Nevada Test Site
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Nuclear testing at the Nevada Test Site began with a 1-kiloton-of-TNT bomb dropped on Frenchman Flat on 27 January 1951. Many of the images of the nuclear era come from the NTS. During the 1950s, the clouds from the 100 atmospheric tests could be seen for almost 100 mi. The city of Las Vegas experienced noticeable seismic effects, and the distant mushroom clouds, St. George, Utah, received the brunt of the fallout of above-ground nuclear testing in the Yucca Flats/Nevada Test Site. Winds routinely carried the fallout of these tests directly through St. George, the vast majority—828 of the 928 total nuclear tests—were underground. Those arrested included the astronomer Carl Sagan and the actors Kris Kristofferson, Martin Sheen, the Nevada Test Site contains 28 areas,1,100 buildings,400 miles of paved roads,300 miles of unpaved roads, ten heliports, and two airstrips. The Nevada Test Site was established as a 680-square-mile area by President Harry Truman on December 18,1950, within the Nellis Air Force Gunnery, the Nevada Test Site was the primary testing location of American nuclear devices from 1951 to 1992,928 announced nuclear tests occurred there. The site is covered with subsidence craters from the testing, the NTS was the United States primary location for tests in the 500-to-1,000 kt range. 126 tests were conducted elsewhere, including most larger tests, many of these occurred at the Pacific Proving Grounds in the Marshall Islands. During the 1950s, the clouds from atmospheric tests could be seen for almost 100 mi. The city of Las Vegas experienced noticeable seismic effects, and the distant mushroom clouds, the last atmospheric test detonation at the Nevada Test Site was Little Feller I of Operation Sunbeam, on 17 July 1962. Although the United States did not ratify the Comprehensive Test Ban Treaty, it honors the articles of the treaty, subcritical tests not involving a critical mass continue. It created a crater 1,280 feet wide and 320 feet deep that can still be seen today, the site was scheduled to be used to conduct the testing of a 1, 100-ton conventional explosive in an operation known as Divine Strake in June 2006. The bomb is an alternative to nuclear bunker busters. After objections from Nevada and Utahs members of Congress, the operation was postponed until 2007, on 22 February 2007, the Defense Threat Reduction Agency officially canceled the experiment. On December 7,2012 the most-recent explosion was conducted, an underground sub-critical test of the properties of plutonium, NTS also performed piggyback testing of effects of nuclear detonation during the above-ground tests. Vehicles, shelters, utility stations, and other structures were placed at distances from the Ground Zero detonation point of each weapon. Homes and commercial buildings were built to typical of American and European cities
