Instruct: Given a question, retrieve documents that can help answer the question.
Query: When was the first nuclear weapon created?
In January 1933, Adolf Hitler was appointed Chancellor of Germany and it quickly became unsafe for Jewish scientists to remain in the country. Leó Szilárd fled to London where he proposed, and in 1934 patented, the idea of a nuclear chain reaction via neutrons. The patent also introduced the term critical mass to describe the minimum amount of material required to sustain the chain reaction and its potential to cause an explosion. (British patent 630,726.) He subsequently assigned the patent to the British Admiralty so that it could be covered by the Official Secrets Act. In a very real sense, Szilárd was the father of the atomic bomb academically.
Also in 1934, Irène and Frédéric Joliot-Curie discovered that artificial radioactivity could be induced in stable elements by bombarding them with alpha particles; Enrico Fermi reported similar results when bombarding uranium with neutrons.
By August 1945, the Allies' Manhattan Project had produced two types of atomic bombs, and the 509th Composite Group of the United States Army Air Forces (USAAF) was equipped with the specialized Silverplate version of the Boeing B-29 Superfortress that could deliver them from Tinian in the Mariana Islands. Orders for atomic bombs to be used on four Japanese cities were issued on July 25. On August 6, one of the modified B-29s dropped a uranium gun-type bomb codenamed "Little Boy" on Hiroshima. Three days later, on August 9, a plutonium implosion-type bomb codenamed "Fat Man" was dropped by another B-29 on Nagasaki. The bombs immediately devastated their targets. Over the next two to four months, the acute effects of the atomic bombings killed 90,000–146,000 people in Hiroshima and 39,000–80,000 people in Nagasaki; roughly half of the deaths in each city occurred on the first day. Large numbers of people continued to die from the effects of burns, radiation sickness, and other injuries, compounded by illness and malnutrition, for many months afterward. In both cities, most of the dead were civilians, although Hiroshima had a sizable military garrison.
Only six countries—United States, Russia, United Kingdom, China, France, and India—have conducted thermonuclear weapon tests. (Whether India has detonated a "true" multi-staged thermonuclear weapon is controversial.) North Korea claims to have tested a fusion weapon , though this claim is disputed. Thermonuclear weapons are considered much more difficult to successfully design and execute than primitive fission weapons. Almost all of the nuclear weapons deployed today use the thermonuclear design because it is more efficient.
The Cold War began in the aftermath, much like in the real world. The United States did not develop nuclear weapons for several more years (they didn't need to finish them, as Superior's early victory in the war meant the Manhattan Project was canceled late in development). However, the real arms race was in the new "Alpha" class super-humans. A handful of other "Alphas" emerged at the end of the war, and in the aftermath, and the Soviet Union was able to "create" several new Alphas, none as powerful as Superior, but still enough to challenge him. In 1949 they also detonated an atomic bomb, and the Cold War began in earnest. Even Superior was uncertain he could survive a nuclear blast. The United States quickly finished its own nuclear program, and like the real world, the fear and paranoia of the Cold War gripped the nation. Senator Joseph McCarthy held his HUAC hearings, but Superior's moral superiority eventually shamed him into closing them.
Compared to fission weapons, thermonuclear designs are exceedingly complex, and staged weapons in particular are so complex that only five countries (USA, Russia, France, UK, China) have created them in more than 70 years of research. The fuels for an H-bomb are also far more difficult to create. Several countries with long-standing nuclear weapons programs, such as India and Pakistan, are suspected of striving towards a hybrid or "boosted" design instead, which is easier. Since both fusion weapons and hybrid designs can at times be referred to as "hydrogen bombs", it cannot be said with certainty at present, what type of weapon North Korea may have been referring to in any given test. At present, analysts are skeptical of the 2016 test being a staged thermonuclear design, while noting that the most recent test, in 2017, was considerably more powerful. In 2018, North Korea had offered and was reportedly preparing for inspections at nuclear and missile sites.
On 10 June 1948, Tamm headed a new group of theorists which included Andrei Sakharov, Vitaly Ginzburg, S.Z. Belenky and Romanov. They followed up Sakharov's ideas for a new thermonuclear weapon and went to KB-11 (now the All-Russian Scientific Research Institute of Experimental Physics) in the closed city of Sarov, Nizhny Novgorod. He started as a junior researcher, then senior, then head of department. In 1952, he received a degree in Physical and Mathematical Sciences with a thesis on kinetic processes of neutrons. This work on neutrons and efficiency continued, along with calculations on nuclear reaction kinetics and energy release of the Soviet Union's first thermonuclear weapon, the RDS-6, tested in 1953; for this he was awarded the Stalin Prize, the first of several awards. He was a leading developer of the RDS-37 - the first Soviet two-stage thermonuclear weapon - most specifically concerned with the power output. Romanov transferred to the new Scientific Research Institute-1011 as head of the theoretical department in 1955. Two years later, his team had developed a new megatonne-yield bomb design. He gained a Ph.D. in Physical and Mathematical Sciences in 1958 and was appointed to professorship of theoretical physics in 1962.
The thermonuclear weapons race between the United States and the Soviet Union exceeded all expectations set out before the scientists who took part. Two countries creating thermonuclear weapons with such energy yields from two different design methods proved to be the crowning achievement for science in the 1950s. Of course, the successful and promising work from both the United States and the Soviet Union only spurred each country to push for stronger weapons, as the floodgates of thermonuclear weapon potential had been opened. This was, of course, entirely the norm at the time considering that the Cold War was in full swing. It was a significant boost to Soviet morale knowing that the Soviet Union's physicists, engineers, scientist, and great minds were able to not only compete with the Americans, but also able to out perform them in some key areas of weapon and technological development.
Edward Teller’s autobiography "Memoirs" reflects positively on Cohen and Urey's centrifuge method for producing U-235 when he writes: “What if we had the atomic bomb a year earlier? The easiest and least expensive method of separating isotopes, a method used throughout the world today, is based on a centrifuge procedure that Harold Urey proposed in 1940. General Groves chose the diffusion method instead. Karl Cohen, Urey’s able assistant during that period, believes that Groves’ decision delayed the atomic bomb by a year.
“If Dr. Cohen is right, atomic bombs of the simple gun design might have become available in the summer of 1944 and, in that case, would surely have been used against the Nazis. Atomic bombs in 1944 might have meant that millions of Jews would not have died, and that Eastern Europe would have been spared more than four decades of Soviet domination.”
There were only seven nuclear bombs in existence in July 1946. The two bombs used in the test were Fat Man plutonium implosion-type nuclear weapons of the kind dropped on Nagasaki. The "Able" bomb was stenciled with the name "Gilda" and decorated with an "Esquire" magazine photograph of Rita Hayworth, star of the 1946 movie, "Gilda". The "Baker" bomb was "Helen of Bikini." This femme-fatale theme for nuclear weapons, combining seduction and destruction, is epitomized by the use in all languages, starting in 1946, of "bikini" as the name for a woman's two-piece bathing suit.
Virtually all thermonuclear weapons deployed today use the "two-stage" design described above, but it is possible to add additional fusion stages—each stage igniting a larger amount of fusion fuel in the next stage. This technique can be used to construct thermonuclear weapons of arbitrarily large yield, in contrast to fission bombs, which are limited in their explosive force. The largest nuclear weapon ever detonated, the Tsar Bomba of the USSR, which released an energy equivalent of over , was a three-stage weapon. Most thermonuclear weapons are considerably smaller than this, due to practical constraints from missile warhead space and weight requirements.
Fusion reactions do not create fission products, and thus contribute far less to the creation of nuclear fallout than fission reactions, but because all thermonuclear weapons contain at least one fission stage, and many high-yield thermonuclear devices have a final fission stage, thermonuclear weapons can generate at least as much nuclear fallout as fission-only weapons.
The power of large bombs is typically measured in kilotons (kt) or megatons of TNT (Mt). The most powerful bombs ever used in combat were the two atomic bombs dropped by the United States to attack Hiroshima and Nagasaki, and the most powerful ever tested was the Tsar Bomba. The most powerful non-nuclear bomb is Russian "Father of All Bombs" (officially Aviation Thermobaric Bomb of Increased Power (ATBIP)) followed by the United States Air Force's MOAB (officially Massive Ordnance Air Blast, or more commonly known as the "Mother of All Bombs").
On October 4, 1957, the Soviet Union launched Sputnik 1, the first artificial satellite of Earth in the history of mankind.
The most notable event of "Operation Castle" was the "Castle Bravo" test. The dry fuel for "Bravo" was 40% Li-6 and 60% Li-7. Only the Li-6 was expected to breed tritium for the deuterium-tritium fusion reaction; the Li-7 was expected to be inert. Yet J. Carson Mark, the head of the Los Alamos Theoretical Design Division, had speculated that "Bravo" could "go big", estimating that the device could produce an explosive yield as much as 20% more than had been originally calculated. It was discovered, because of the unexpected larger yield, that the Li-7 in the device also undergoes breeding that produces tritium. In practice, "Bravo" exceeded expectations by 150%, yielding 15 Mt — about 1,000 times more powerful than the "Little Boy" weapon used on Hiroshima. "Castle Bravo" remains to this day, the largest detonation ever carried out anywhere by the United States, and the fifth largest H-bomb detonation in the world.
The process was invented in Hanau, Germany in 1917. Heraeus Vacuumschmelze and Dr. Wilhelm Rohn applied for a patent on vacuum melting on 12 January 1918 and were granted a German patent DE 345161. E.F. Northrup built the first prototype of a vacuum induction furnace in the United States of America in 1920. Medium frequency furnaces were seen soon afterwards in England and Sweden in 1927. The process was initially developed to refine certain special metals such as cobalt and nickel. As these metals and alloys became more common, the process of VIM became more widely used. VIM now helps to melt a variety of metals for aircraft and nuclear applications.
In 1977, Freeman became the first hospital to use ultrasound in diagnostic services and nuclear medicine.
Second, and more powerful plutonium implosion atomic bomb, Fat Man, is dropped on Nagasaki from a different "Silverplate" B-29 named "Bockscar", flown by Maj. Charles Sweeney (Atomic bombing of Nagasaki)
The UN officially came into existence on 24 October 1945 upon ratification of the Charter by the five then-permanent members of the Security Council and by a majority of the other 46 signatories. On 17 January 1946, the Security Council met for the first time at Church House, Westminster, in London, United Kingdom.
The development of the cavity magnetron in the UK made possible the production of electromagnetic waves of a small enough wavelength (microwaves). American engineer Percy Spencer is generally credited with inventing the modern microwave oven after World War II from radar technology developed during the war. Named the "Radarange", it was first sold in 1946. Raytheon later licensed its patents for a home-use microwave oven that was first introduced by Tappan in 1955, but these units were still too large and expensive for general home use. Sharp Corporation introduced the first microwave oven with a turntable between 1964 and 1966. The countertop microwave oven was first introduced in 1967 by the Amana Corporation. After Sharp introduced low-cost microwave ovens affordable for residential use in the late 1970s, their use spread into commercial and residential kitchens around the world. In addition to their use in cooking food, types of microwave ovens are used for heating in many industrial processes.
As of April 2012 there were thirty one countries that have civil nuclear power plants, of which nine have nuclear weapons, with the vast majority of these nuclear weapons states having first produced weapons, before commercial fission electricity stations.
Moreover, the re-purposing of civilian nuclear industries for military purposes would be a breach of the Non-proliferation treaty, of which 190 countries adhere to.
The basic principle of the Teller–Ulam configuration is the idea that different parts of a thermonuclear weapon can be chained together in "stages", with the detonation of each stage providing the energy to ignite the next stage. At a bare minimum, this implies a "primary" section that consists of an implosion-type fission bomb (a "trigger"), and a "secondary" section that consists of fusion fuel. The energy released by the "primary" compresses the "secondary" through a process called "radiation implosion", at which point it is heated and undergoes nuclear fusion. This process could be continued, with energy from the secondary igniting a third fusion stage; Russia's AN602 "Tsar Bomba" is thought to have been a three-stage fission-fusion-fusion device. Theoretically by continuing this process thermonuclear weapons with arbitrarily high yield could be constructed. This contrasts with fission weapons which are limited in yield.
In 1945, the specific heating effect of a high-power microwave beam was accidentally discovered by Percy Spencer, an American self-taught engineer from Howland, Maine. Employed by Raytheon at the time, he noticed that microwaves from an active radar set he was working on started to melt a chocolate bar he had in his pocket. The first food deliberately cooked with Spencer's microwave was popcorn, and the second was an egg, which exploded in the face of one of the experimenters. To verify his finding, Spencer created a high density electromagnetic field by feeding microwave power from a magnetron into a metal box from which it had no way to escape. When food was placed in the box with the microwave energy, the temperature of the food rose rapidly. On 8 October 1945, Raytheon filed a United States patent application for Spencer's microwave cooking process, and an oven that heated food using microwave energy from a magnetron was soon placed in a Boston restaurant for testing.
The novel then goes back in time to 1898, when the Marie Curie and her husband discover radioactivity. The story presents a brief timeline that continues up into the 1930s, when James Chadwick discovers neutrons and the discovery of nuclear fission. The novel takes a shift, and begins to discuss the political environment. Leo Szilard becomes troubled as he sees the dangers that these nuclear weapons could produce, and travels with Eugene Wigner to talk with Albert Einstein about the possibility of Nazi scientists creating a bomb. News soon reaches the United States president, who authorizes the precursor to the Manhattan Project. After the bombing of Pearl Harbor, the United States founds covertly Los Alamos National Laboratory and other cities to create nuclear weapons. The scientists and their families are sworn to secrecy. Soon, the scientists at Los Alamos discover how to create a nuclear chain reaction, leading to the development of the first atomic weapons: Little Boy and Fat Man.
Some other types of weapons outlined and developed during the 1950—60s were designed as carriers for nuclear weapons – among them, the Saab A36, a strategic bomber, Bandkanon 1, a 155 mm artillery piece, and Robot 08, an anti-ship missile. These claims have been circulating since the times when the defense studies were still classified. There were certainly first drafts concerning the physical shape of Swedish nuclear weapon when the Saab A36 was under development, but the project A36 was soon abandoned in favor of the Saab AJ 37 Viggen when the first detailed military (rather than merely physical or technical) studies were conducted in 1961–62. Thus, even if the A36 was not designed to be an integral part of the nuclear weapons program itself, it was constructed specifically as a nuclear weapons carrier. A36 pilots were to specialize in this task.
The United Kingdom became a nuclear power in 1952, and their nuclear arsenal peaked at just under 500 nuclear weapons in 1981. France became a nuclear power in 1960, and French nuclear stockpiles peaked at just over 500 nuclear weapons in 1992. China developed its first nuclear weapon in 1964; its nuclear stockpile increased until the early 1980s, when it stabilized at between 200 and 260. India became a nuclear power in 1974, while Pakistan developed its first nuclear weapon in the 1980s. India and Pakistan currently have around one hundred nuclear weapons each. Pakistan's nuclear stockpile has increased rapidly, and it is speculated that Pakistan might have more nuclear weapons than the United Kingdom within a decade.
North Korea replied in regard to the nuclear issue in order to draw attention to the “unique security environment” that is threatened and blackmailed by the largest nuclear state. It sought to draw attention to certain points: In 1957 the United States introduced the first nuclear weapon into South Korea and thus began a presence of nuclear weapon in the land; in the 1970s the number of nuclear weapons reached over 1,000 on the Korean Peninsula alone and thereby made the Korean peninsula the most densely populated nuclear weapons zone; in 2002 the U.S. administration named the D.P.R.K. as part of the axis of evil and gave a “strong message” to the entire international community that the country is to be eliminated; and the “same administration” listed the D.P.R.K. onto its list of nuclear pre-emptive strikes and that, compounded with all these nuclear weapons, the U.S. and South Korea “every year take part in military drills as mentioned several times in the current session. In March 2013 when the situation was almost on the brink of war and it was the time when the international community realised how dangerous the situation was, [which] means [an] outbreak of nuclear war.” This also occurred with a massive arms build-up of nuclear weapons carried by the aircraft carrier , submarines and the B52 across the ocean. These events were viewed as blackmail and culminated in threatening the survival of the Korean nation as a whole (north and south). As a result of the unique security environment, the D.P.R.K. has no option but to go nuclear to defend its people and not allow “nuclear weapons to drop over the hills of the people. The nuclear deterrent made a great contribution to lasting peace in the Korean Peninsula and the world.” In addition, in accord with “the last speaker,” North Korea made a few more points: Israel has no justification to talk of another country as a full-fledged nuclear state; it is a “cancer in middle east;” it is “disturbing peace and security and shifting blame on all other regional countries;” and Israel and the U.S. are “making noise” about the D.P.RK. but are “mum and quiet and silent over the nuclear weapon of Israel.