When was the Castle Bravo test performed?
Castle Bravo
Castle Bravo was the first in a series of high-yield thermonuclear weapon design tests conducted by the United States at Bikini Atoll, Marshall Islands, as part of "Operation Castle". Detonated on March 1, 1954, the device was the most powerful nuclear device detonated by the United States and its first lithium deuteride fueled thermonuclear weapon. Castle Bravo's yield was 15 megatons of TNT, 2.5 times the predicted 6.0 megatons, due to unforeseen additional reactions involving Li, which led to the unexpected radioactive contamination of areas to the east of Bikini Atoll.
Mark 24 nuclear bomb
The Castle Yankee thermonuclear test was the first bomb to use enriched Lithium-6 isotope, up to perhaps 40% enrichment (the earlier Castle Bravo test had used the same enriched lithium combination but was not weaponised i.e. was not built as a deployable bomb). The device tested was called the Runt II design; it was reportedly very similar to the Runt design tested in Castle Romeo, other than the enrichment level.
Castle Bravo
The device was called SHRIMP and had the same basic configuration (radiation implosion) as the "Ivy Mike" wet device, except with a different type of fusion fuel. "SHRIMP" used lithium deuteride (LiD), which is solid at room temperature; "Ivy Mike" used cryogenic liquid deuterium (D), which required elaborate cooling equipment. "Castle Bravo" was the first test by the United States of a practical deliverable fusion bomb, even though the TX-21 as proof-tested in the Bravo event was not weaponized. The successful test rendered obsolete the cryogenic design used by "Ivy Mike" and its weaponized derivative, the "JUGHEAD", which was slated to be tested as the initial "Castle Yankee". It also used a 7075 aluminum 9.5 cm thick ballistic case. Aluminum was used to drastically reduce bomb's weight and simultaneously provided sufficient radiation confinement time to raise yield, a departure from the heavy stainless steel casing (304L or MIM 316L) employed by contemporary weapon-projects.
Tunguska event
The 15-megaton (Mt) estimate represents an energy about 1,000 times greater than that of the atomic bomb dropped on Hiroshima, Japan—roughly equal to that of the United States' Castle Bravo (15.2 Mt) ground-based thermonuclear detonation on 1 March 1954, and about one-third that of the Soviet Union's Tsar Bomba explosion on 30 October 1961 (which, at 50 Mt, is the largest nuclear weapon ever detonated).
British hydrogen bomb programme
The successful test of an atomic bomb represented an extraordinary scientific and technological achievement. Britain became the world's third nuclear power, reaffirming its status as a great power, but hopes that the United States would be sufficiently impressed to restore the Special Relationship were soon dashed. On 1 November 1952, the United States conducted Ivy Mike, the first successful test of a true thermonuclear device (also known as a hydrogen bomb). Due to its physical size and use of cryogenic liquid deuterium, it was not suitable for use as a deliverable weapon, but the Castle Bravo test on 1 March 1954 used a much smaller device with solid lithium deuteride. Boosted by the nuclear fusion reaction in lithium-7, the yield of was more than twice what had been expected, and indeed was the largest detonation the Americans would ever carry out. This resulted in widespread radioactive fallout that affected 28 Americans, 236 Marshall Islanders, and the 23 crewmen of a Japanese fishing boat, the "Daigo Fukuryū Maru" ("Lucky Dragon No. 5"). Meanwhile, the Soviet Union tested Joe 4, a boosted fission weapon with a yield of on 12 August 1953. This was followed by Joe 19, a true two-stage thermonuclear weapon on 20 November 1954.
Castle Bravo
This resultant extra fuel (both lithium-6 and lithium-7) contributed greatly to the fusion reactions and neutron production and in this manner greatly increased the device's explosive output. The test used lithium with a high percentage of lithium-7 only because lithium-6 was then scarce and expensive; the later "Castle Union" test used almost pure lithium-6. Had sufficient lithium-6 been available, the usability of the common lithium-7 might not have been discovered.
History of nuclear weapons
In the beginning, almost all nuclear tests were either atmospheric (conducted above ground, in the atmosphere) or underwater (such as some of the tests done in the Marshall Islands). Testing was used as a sign of both national and technological strength, but also raised questions about the safety of the tests, which released nuclear fallout into the atmosphere (most dramatically with the Castle Bravo test in 1954, but in more limited amounts with almost all atmospheric nuclear testing).
Nuclear testing at Bikini Atoll
On the Marshall Islands, the detonation of Castle Bravo was the cause of most of the radiation exposure to the surrounding populations. The fallout levels attributed to the Castle Bravo test are the highest in history. The exposure to fallout has been linked to increase the likelihood of several types of cancer such as leukemia and thyroid cancer. The relationship between I-131 levels and thyroid cancer is continuing to be researched. There are also correlations between fallout exposure levels and diseases such as thyroid disease like hypothyroidism. Populations of the Marshall Islands that received significant exposure to radionuclides have a much greater risk of developing cancer. The Castle Bravo test detonation produced an explosion of approximately 15 megatons, which is about three times its predicted value. Populations neighboring the test site were exposed to high levels of radiation resulting in mild radiation sickness of many (nausea, vomiting, diarrhea). Several weeks later, many people began suffering from alopecia (hair loss) and skin lesions as well. The female population of the Marshall Islands have a sixty times greater cervical cancer mortality than a comparable mainland United States population. The Islands populations also have a five time greater likelihood of breast or gastrointestinal mortality, and lung cancer mortality is three times higher than the mainland population. The male population on the Marshall Islands lung cancer mortality is four times greater than the overall United States rates, and the oral cancer rates are ten times greater.
Castle Grande
McDougal then loaned his old friend and political mentor, Senator William Fulbright, $700,000 to buy out the bulk of Ward's remaining holdings. The net effect was to remove Ward's non-recourse loan from the Madison books and generate substantial sales profits and commissions for Madison. The transactions were designed to be confusing to keep the regulators from finding Ward's loan and Madison's full investment in Castle Grande. The federal thrift examiners arrived the first week of March, 1986. The Dean Paul loan done on February 28.
Castle Bravo
The Shrimp device design later evolved into the Mark 21 nuclear bomb, of which 275 units were produced, weighing and measuring long and in diameter. This 4-megaton bomb was produced until July 1956. In 1957, it was converted into the Mark 36 nuclear bomb and entered into production again.
Rongelap Atoll
Irradiated debris fell up to deep over the island. A United States military medical team visited the island with geiger counters the day after the fallout, but left without telling the islanders of the danger they had been exposed to. Virtually all the inhabitants experienced severe radiation sickness, including itchiness, sore skin, vomiting, diarrhea, and fatigue. Their symptoms also included burning eyes and swelling of the neck, arms, and legs. The inhabitants were forced to abandon the islands, leaving all their belongings, three days after the test. They were relocated to Kwajalein for medical treatment. Six days after the Castle Bravo test, the U.S government set up a secret project to study the medical effects of the weapon on the residents of the Marshall Islands.
History of the Marshall Islands
From 1946 to 1958, the early years of the Cold War, the United States tested 67 nuclear weapons at its Pacific Proving Grounds located in the Marshall Islands, including the largest atmospheric nuclear test ever conducted by the U.S., code named Castle Bravo. "The bombs had a total yield of 108,496 kilotons, over 7,200 times more powerful than the atomic weapons used during World War II." With the 1952 test of the first U.S. hydrogen bomb, code named "Ivy Mike," the island of Elugelab in the Enewetak atoll was destroyed. In 1956, the United States Atomic Energy Commission regarded the Marshall Islands as "by far the most contaminated place in the world."
Nuclear technology
Military accidents usually involve the loss or unexpected detonation of nuclear weapons. The Castle Bravo test in 1954 produced a larger yield than expected, which contaminated nearby islands, a Japanese fishing boat (with one fatality), and raised concerns about contaminated fish in Japan. In the 1950s through 1970s, several nuclear bombs were lost from submarines and aircraft, some of which have never been recovered. The last twenty years have seen a marked decline in such accidents.
Castle Union
The test took place on April 26, 1954 at Bikini atoll of the Marshall Islands, on a barge moored in the lagoon, off Yurochi island. The yield of 6.9 megatons of TNT was somewhat higher than the predicted 3-4 megatons. Although the barge had been moored in over of water, the test left a crater in diameter and deep in the bottom of the lagoon.
Duck and cover
A notable comparison to underline this is found when one compares the 50 megaton air-burst Tsar Bomba, which produced no concentrated local/early fallout, and thus no known deaths from radiation, with the surface burst of the 15 megaton Castle Bravo, which in comparison, due to the local fallout produced, was implicated in the death of 1 of 23 crew on the Lucky Dragon and made the entire Bikini Atoll unfit for further nuclear testing until enough time elapsed and the intensity of the radiation field had decayed to acceptable levels.
Furthermore, regardless of if a nuclear attack on a city is of the surface or air-burst variety or a mixture of both, the advice to shelter in place, in the interior of well-built homes, or if available, fallout shelters, as suggested in the film "Duck and Cover", will drastically reduce one's chance of absorbing a hazardous dose of radiation. A real-world example of this occurred after the Castle Bravo test where, in contrast to the crew of the Lucky Dragon, the firing crew that triggered the explosion safely sheltered in their firing station until after a number of hours had passed and the radiation levels outside fell to dose rate levels safe enough for an evacuation to be considered. The comparative safety experienced by the Castle Bravo firing crew served as a proof of concept to civil defense personnel that shelter in place (or "buttoning up" as it was known then) is an effective strategy in mitigating the potentially serious health effects of local fallout.
Castlemore Moat
The motte and bailey castle was constructed in the 12th century AD by Raymond FitzGerald (Raymond le Gros), one of the commanders of the Norman invasion of Ireland. The land of Forth O'Nolan was granted to Raymond and he married Basilia, sister of Strongbow. They lived together at Castlemore.
Castle Bravo
A Japanese fishing boat, "Daigo Fukuryū Maru" (Lucky Dragon No.5), came in direct contact with the fallout, which caused many of the crew to grow ill; one died of a secondary infection. This resulted in an international incident and reignited Japanese concerns about radiation, especially as Japanese citizens were once more adversely affected by US nuclear weapons. The official US position had been that the growth in the strength of atomic bombs was not accompanied by an equivalent growth in radioactivity released. Japanese scientists who had collected data from the fishing vessel disagreed with this.
Combat Missions
Bravo vs Delta
Pacific Proving Grounds
The United States conducted 105 atmospheric and underwater (i.e., not underground) nuclear tests in the Pacific, many of which were of extremely high yield. While the Marshall Islands testing composed 14% of all U.S. tests, it composed nearly 80% of the total yields of those detonated by the U.S., with an estimated total yield of around 210 megatons, with the largest being the 15 Mt Castle Bravo shot of 1954 which spread considerable nuclear fallout on many of the islands, including several which were inhabited, and some that had not been evacuated.
The Bravo
The Bravo is a novel by James Fenimore Cooper first published in 1831 in three volumes. Inspired by a trip to Europe where he traveled through much of Italy, the novel is set in Venice. "The Bravo" is the first of Cooper's three novels to be set in Europe. This group of three novels, which one critic would call Cooper's "European trilogy", include "The Heidenmauer" and "". Like his other novels set in Europe, "The Bravo" was not very well received in the United States. The book largely focuses on political themes, especially the tension between the social elite and other classes.
Anastasio Ballestrero
Ballestrero agreed to scientific testing being performed on the Shroud of Turin in October 1978 but refused to permit radiocarbon dating testing as it required removing samples from the shroud itself. Once technical improvements made it possible to use samples the size of postage stamps the cardinal permitted samples to be cut in April 1988 which he himself supervised to ensure it was carried out in an appropriate manner. These would be tested in three labs in Switzerland as well as in the United States and the United Kingdom.
Castle Koon
The Koon shot of Operation Castle was a test of a University of California Radiation Laboratory (UCRL), now Lawrence Livermore National Laboratory (LLNL) designed thermonuclear device.
Castle Bravo
The device was mounted in a "shot cab" on an artificial island built on a reef off Namu Island, in the Bikini Atoll. A sizable array of diagnostic instruments was trained on it, including high-speed cameras trained through an arc of mirror towers around the shot cab.
Pacific Proving Grounds
Many of the islands which were part of the Pacific Proving Grounds are still contaminated from the nuclear fallout, and many of those who were living on the islands at the time of testing have suffered from an increased incidence of various health problems. Through the Radiation Exposure Compensation Act of 1990, at least $759 million has been paid to Marshall Islanders as compensation for their exposure to U.S. nuclear testing. Following the Castle Bravo accident, the U.S. paid $15.3 million to Japan.
Dwayne Bravo
On the West Indies tour of Australia in 2005, Bravo was controversially not picked for the first Test at Brisbane in which the West Indies were beaten convincingly. He was recalled for the second Test in Hobart and made a superb 113, after coming in at a very difficult stage for the West Indies. His innings lifted the West Indies and helped them regain some pride, forcing the Australians to bat for a second time in the match. In the third and final match of the series at Adelaide, he bowled a superb spell in the Australians first innings taking 6 for 84.
El Castillo del Terror (2007)
El Castillo del Terror (2007) was a professional wrestling event, their annual "El Castillo del Terror" event produced by the International Wrestling Revolution Group (IWRG). IWRG has held an "Castillo del Terror" branded show since 2005, usually late in the year, making this year's event the third overall event in the series. The event took place on November 3, 2013, at Arena Naucalpan in Naucalpan, State of Mexico, IWRG's main arena. The main event was the eponymous "Castillo del Terror" (Spanish for "Castle of Terror") Steel cage match where the last person eliminated was forced to unmasked per the match stipulation. In the end the ten-man match saw Rayo de Jalisco, Jr. defeat Enterrador 2000, forcing him to unmask after the match.
Darren Bravo
Darren Bravo is the first batsman in history to score a test century in the fourth innings of a Day/Night test match when he scored 116 in that innings.He was also the first ever left handed batsman to have scored a test hundred in an innings of a Day-night test match.
Castelmur Castle (Bondo)
After the fall of the Western Roman Empire the Castelmur next appears in 842 as "castellum ad Bergalliam". At that time it was owned by the Emperor and held by Constantius of Sargans. It included the "porta bergalliae" a customs and toll station located nearby. In 960 Emperor Otto I granted the castle and right to collect tolls to the Bishop of Chur to help secure this important alpine trade route. In 988 Emperor Otto III confirmed his grandfather's grant to the Bishop and specifically mentioned both the castle and the nearby Nossa Donna Church. The current tower was probably built around 1200.
Operation Crosstie
The Faultless test was a calibration test conducted in a mine cavity 3,200 feet beneath the Hot Creek Valley near Tonopah, Nevada, with a yield of around 1 megaton. This test was conducted to see if the land was fit for testing a 5 megaton thermonuclear warhead for the Spartan missile. The test failed because of the large degree of faulting that resulted in the area around the test. It was decided that the land was unfit for multi-megaton nuclear tests, so a similar calibration test was conducted at Amchitka Island, Alaska, in the fall of 1969 during Operation Mandrel.
Downwinders
One of these many tests, the March 1, 1954, explosion of Castle Bravo, a U.S. thermonuclear device, was responsible for most of the radiation the Marshall Islanders were exposed to. The fallout-related doses of this single test are believed to be the highest recorded in the history of worldwide nuclear testing. Many of the Marshall Islands which were part of the Pacific Proving Grounds remain contaminated by nuclear fallout, and many of those downwinders who were living on the islands at the time of testing have suffered from a highly increased incidence of several types of cancers and birth defects.
Castle Bravo
The detonation took place at 06:45 on March 1, 1954, local time (18:45 on February 28 GMT).
When Bravo was detonated, within one second it formed a fireball almost across. This fireball was visible on Kwajalein atoll over away. The explosion left a crater in diameter and in depth. The mushroom cloud reached a height of and a diameter of in about a minute, a height of and in diameter in less than 10 minutes and was expanding at more than . As a result of the blast, the cloud contaminated more than of the surrounding Pacific Ocean, including some of the surrounding small islands like Rongerik, Rongelap, and Utirik.
B46 nuclear bomb
The design history of the B46 apparently derives most immediately from the older, larger Mark 21 nuclear bomb design, which was a design derivative of the Shrimp design which was the first US solid fueled thermonuclear bomb test fired in the Castle Bravo test.
Operation Castle
"Operation Castle" was organized into seven experiments, all but one of which were to take place at Bikini Atoll. Below is the original test schedule (as of February 1954).
British nuclear testing in the United States
The Nevada Test Site would be cheaper than Monte Bello, although the cost would be paid in scarce dollars. Information gathered would have to be shared with the Americans, who would not share their own data. It would not be possible to test from a ship, and the political advantages in demonstrating that Britain could develop and test nuclear weapons without American assistance would be foregone, and the Americans were under no obligation to make the test site available for subsequent tests. Also, as Lord Cherwell noted, an American test meant that "in the lamentable event of the bomb failing to detonate, we should look very foolish indeed." In the end, Monte Bello was chosen, and the first British atomic bomb was tested there in Operation Hurricane on 3 October 1952. The next British test series, Operation Totem, was conducted at Emu Field in South Australia, but at their conclusion, the British government formally requested a permanent testing site from the Australian government, which led to the agreement on the use of the Maralinga test site in August 1954. The first of the British nuclear tests at Maralinga was held in September 1956.
While British atomic bomb development represented an extraordinary scientific and technological achievement, hopes that the United States would be sufficiently impressed to restore the nuclear Special Relationship were dashed. In November 1952, the United States conducted Ivy Mike, the first successful test of a true thermonuclear device or hydrogen bomb. Britain was therefore still several years behind in nuclear weapons technology. The Defence Policy Committee, chaired by Churchill and consisting of the senior Cabinet members, considered the political and strategic implications, and concluded that "we must maintain and strengthen our position as a world power so that Her Majesty's Government can exercise a powerful influence in the counsels of the world." In July 1954, Cabinet agreed to proceed with the development of thermonuclear weapons.
Pacific Proving Grounds
Six very large nuclear tests were conducted at the Bikini Atoll and the Enewetak Atoll as part of Operation Castle in 1954. The most notable was Castle Bravo, which was the first deployable (dry fuel) hydrogen bomb developed by the United States. Its yield, at 15 Mt, was over twice as powerful as was predicted, and was the largest weapon ever detonated by the United States. It spread nuclear fallout over a wide area, including the Enewetak Atoll, Rongerik Atoll, Ailinginae Atoll, and Rongelap Atoll. The U.S. Navy evacuated the islanders within the next few days, but many of the natives exposed suffered from cancers and a high incidence of birth defects in the years following the event. The fishermen aboard the Japanese fishing vessel, the "Daigo Fukuryu Maru", were additionally exposed and one man died soon after from complications of radiation sickness, resulting in considerable international controversy.
Casoni test
The test was described in 1912 by Tomaso Casoni.
Castle Yankee
It was detonated on May 5, 1954, at Bikini Atoll of the Marshall Islands, on a barge moored in the middle of the crater from the Castle Union test.
Bokak Atoll
While en route from the US to Asia in April, 1953, LST 1138, later commissioned as , dropped anchor at Bokak to search for rumored Japanese stragglers. The landing party noted the remains of the wartime outpost, but found no signs of any current occupants.
In 1954, the experience of large scale fallout from the Castle Bravo nuclear test on Bikini Atoll led to a pre-planned aerial survey of atolls adjacent to the subsequent Castle Romeo test, timed at one and four hours after the shot. The aircraft were equipped with gamma radiation detectors designed to measure ground contamination from altitudes of . An overflight of Sibylla Island measured 1.0 mrem/hr (10 μGy) an hour after the shot, dropping to 0.4 mrem/hr (4 μGy) three hours later. In 1957, Bokak was surveyed as a site for nuclear weapons testing as a part of Operation Hardtack, but due the number of improvements required to develop it, was passed over in favor of reusing the Bikini, Enewetak, and Nevada test sites. The atoll came under renewed consideration for use during Operation Dominic, but by that time the potential for political fallout from nuclear testing within a United Nations Trust Territory was deemed too great.
Castel Nuovo
Castel Nuovo (Italian: "New Castle"), often called Maschio Angioino (Italian: "Angevin Keep"), is a medieval castle located in front of Piazza Municipio and the city hall (Palazzo San Giacomo) in central Naples, Campania, Italy. Its scenic location and imposing size makes the castle, first erected in 1279, one of the main architectural landmarks of the city. It was a royal seat for kings of Naples, Aragon and Spain until 1815.
Nuclear testing at Bikini Atoll
Six days after the Castle Bravo test, the U.S government set up a secret project to study the medical effects of the weapon on the residents of the Marshall Islands.
Human radiation experiments
In the Marshall Island, indigenous residents and crewmembers of the fishing boat "Lucky Dragon No. 5" were exposed to the high yields of radioactive testing during the Castle Bravo explosions conducted at Bikini Atoll. Researchers subsequently exploited this ostensibly "unexpected" turn of events by conducting research on the onset of effects from radiation poisoning as part of Project 4.1, raising ethical questions as to both the specific incident and the broader phenomenon of testing in populated areas.
Ebeye Island
Some of the residents of Ebeye are refugees or descendants of refugees from the effects of the 15- Castle Bravo nuclear test at Bikini Atoll on 1 March 1954. The detonation unexpectedly rained nuclear fallout and two inches (50 mm) of radioactive snow on nearby Rongelap Atoll, which had not been evacuated as had Bikini. The 1954 American authorities then evacuated Rongelap and were returned in 1957 with extensive medical surveillance. In 1985, Greenpeace evacuated the inhabitants of Rongelap to Mejato (island in Kwajalein atoll). Ebeye was the final destination for many of them.
Castle Romeo
Like the Ivy Mike and Castle Bravo tests, a large percentage of the yield was produced by fast fission of the natural uranium "tamper"; 7 megatons of the yield were from this source.
Castle Mountain
The first climber to reach the top of Castle Mountain was Arthur P. Coleman, a professor at the University of Toronto, in 1884. Lawrence Grassi and P. Cerutti, both from Canmore, were the first to climb Eisenhower Tower in 1926.
Wolfe–Spence tests
Wolfe–Spence Programming Aptitude tests, or Wolfe–Spence tests, are a series of tests introduced in 1972 by Jack M. Wolfe, PhD, used to determine how likely a candidate is to succeed in further classes and tests. They are administrated by Walden Personnel Testing and Consulting Inc.
Darren Bravo
Bravo's seventh Test hundred came in the first Test of the Australia tour of 2015–16, in Bellerive Oval, Hobart. He scored 108 off 177 balls in the first innings and eventually lost the match by an innings.
Operation Castle
Because "Castle Bravo" greatly exceeded its expected yield, JTF-7 was caught unprepared. Much of the permanent infrastructure on Bikini Atoll was heavily damaged. The intense thermal flash ignited a fire at a distance of on the island of Eneu (base island of Bikini Atoll). The ensuing fallout contaminated all of the atoll, so much so, that it could not be approached by JTF-7 for 24 hours after the test, and even then exposure times were limited. As the fallout spread downwind to the east, more atolls were contaminated by radioactive calcium ash from the incinerated underwater coral banks. Although the atolls were evacuated soon after the test, 239 Marshallese on the Utirik, Rongelap, and Ailinginae Atolls were subjected to significant levels of radiation. 28 Americans stationed on the Rongerik Atoll were also exposed. Follow-up studies of the contaminated individuals began soon after the blast as Project 4.1, and though the short-term effects of the radiation exposure for most of the Marshallese were mild and/or hard to correlate, the long-term effects were pronounced. Additionally, 23 Japanese fishermen aboard "Daigo Fukuryū Maru" were also exposed to high levels of radiation. They suffered symptoms of radiation poisoning, and one crew member died in September 1954.
Joseph Rotblat
At St Bartholomew's, Rotblat worked on the effects of radiation on living organisms, especially on ageing and fertility. This led him to an interest in nuclear fallout, especially strontium-90 and the safe limits of ionising radiation. In 1955, he demonstrated that the contamination caused by the fallout after the Castle Bravo test at Bikini Atoll nuclear test by the United States had been far greater than that stated officially. Until then the official line had been that the growth in the strength of atomic bombs was not accompanied by an equivalent growth in radioactivity released. Japanese scientists who had collected data from a fishing vessel, the "Lucky Dragon", which had inadvertently been exposed to fallout, disagreed with this. Rotblat was able to deduce that the bomb had three stages and showed that the fission phase at the end of the explosion increased the amount of radioactivity by forty times. His paper was taken up by the media and contributed to the public debate that resulted in the ending of atmospheric tests by the Partial Nuclear Test Ban Treaty.
Project GABRIEL
During the Cold War era, there was an escalation of the atmosphere testing of nuclear weapons. After the atomic bomb in 1945, testing continued and the scale increased with the first hydrogen bomb in 1952. Soon after the United States tested the hydrogen bomb, the USSR followed, in 1953. The mushroom clouds that occurred from the explosions released radioactive isotopes in mass quantities.
The first comprehensive study of this problem began in spring 1949 with a one-man project called GABRIEL, conducted by Nicholas M. Smith Jr. at Oak Ridge National Laboratory. Smith produced his first report in 1949. Project GABRIEL was revived in mid-1951 because bombs that were dropped had brought up concerns people had about the dangers of strontium-90. United States Atomic Energy Commission (AEC) was interested by GABRIEL's report though they said it was lacking in hard data and needed independent confirmation of the tests.
After reviewing Project GABRIEL in 1953, it was given first priority status. The secret project would define "practical limits" for using atomic weapons. A task team was assembled and the codename used was "Project HORN." In 1954, AEC argued that fallout was harmless because there wasn't enough evidence to prove that fallout would harm humans, animals, or crops. The AEC campaign persuaded the public that the worldwide fallout was harmless. This claim was later disputed when scientists announced publicly that there was no safe level of radiation. This was confirmed in a confidential report by a geneticist for the AEC. By 1954 and the Castle Bravo incident, it was obvious that radioactive fallout was dangerous to humans. United States Atomic Energy Commission Division of Biology and Medicine dealt with efforts directed towards experimental and field studies and the correlation of data dealing with Project GABRIEL.
The RAND Corporation, Laboratories at Columbia University, AEC's New York office, the University of Chicago, an exclusive group of scientists, UCLA, and the United States Air Force were all involved in collection and testing of samples from around the world for radioactive fallout.
Nuclear weapons of the United States
The U.S. program of atmospheric nuclear testing exposed a number of the population to the hazards of fallout. Estimating exact numbers, and the exact consequences, of people exposed has been medically very difficult, with the exception of the high exposures of Marshall Islanders and Japanese fishers in the case of the Castle Bravo incident in 1954. A number of groups of U.S. citizens—especially farmers and inhabitants of cities downwind of the Nevada Test Site and U.S. military workers at various tests—have sued for compensation and recognition of their exposure, many successfully. The passage of the Radiation Exposure Compensation Act of 1990 allowed for a systematic filing of compensation claims in relation to testing as well as those employed at nuclear weapons facilities. By June 2009 over $1.4 billion total has been given in compensation, with over $660 million going to "downwinders".
Alvin C. Graves
Graves became dismissive of the radiation risks from nuclear testing while serving as test director for the Nevada Test Site shots during the 1950s. He announced that the risks from fallout were "concocted in the minds of weak malingerers." As a spokesman for the Nevada Test Site, he spoke in local areas around Nevada assuring the population of no danger from the activities there. As the head of the Los Alamos Laboratory's J (Test) Division, he was the scientific director or deputy director of most of the nuclear tests from 1948 through the 1950s, including the Desert Rock exercises which exposed military personnel to radiation, and the Castle Bravo test that irradiated many native islanders and test personnel. Asked to testify before the Joint Committee on Atomic Energy on the danger of radiation causing cancer, Graves replied:
Castle Yankee
Although it had been predicted to produce a yield of 6 to 10 megatons, it actually produced a yield of 13.5 megatons, the second-largest ever yield in a U.S. fusion weapon test. Like the Mike, Bravo and Romeo tests, a large percentage of the yield was produced by fast fission of the natural uranium tamper. Of the total yield, 7 megatons were from fission; the other 6.5 megatons were from fusion reactions. The high fusion yield was due to the enriched fuel and set a U.S. record that stood until Hardtack Poplar in 1958.
Castello Brown
The castle's site is well suited for harbour defence, and appears to have been so used since the 15th century. According to the Record Office of Genoa, cannon batteries were constructed on the site in the early 16th century, and military engineer drew up plans for a full fortress circa 1554. The resultant castello was completed by 1557, and, in 1575, was instrumental in turning back an attack on the town by Giò Andrea Doria. The structure was enlarged from 1622 to 1624, and survived in this form for a century and a half. The little tower was destroyed in 1798 by an English attack during Napoleon's Ligurian Republic. The castello was abandoned after the Congress of Vienna in 1815.
Castle Bravo
The fallout from "Castle Bravo" and other testing on the atoll also affected islanders who had previously inhabited the atoll, and who returned there some time after the tests. This was due to the presence of radioactive caesium-137 in locally grown coconut milk. Plants and trees absorb potassium as part of the normal biological process, but will also readily absorb caesium if present, being of the same group on the periodic table, and therefore very similar chemically. Islanders consuming contaminated coconut milk were found to have abnormally high concentrations of caesium in their bodies and so had to be evacuated from the atoll a second time.
Castle Bravo
Stratospheric fallout particles of strontium-90 from the test were later captured with balloon-borne air filters used to sample the air at stratospheric altitudes, the research (Project Ashcan) was conducted to better understand the stratosphere, fallout times and arrive at more accurate meteorological models after hindcasting.
Claudio Bravo
Barcelona
Claudio Bravo
On his return to the Camp Nou on 19 October 2016, in a Champions League group stage match, Bravo was sent off after handling the ball outside of his area, in an eventual 0–4 loss. After a number of high profile errors, including being beaten by all six shots on target in his previous two appearances for City, he was dropped to the bench in February 2017, with backup Willy Caballero replacing him; having finished with the worst save success rate (54.1%) among all goalkeepers, he was named by many journalists as one of the worst signings of the season.
Castle Yankee
The test device, code-named "Jughead", had been prepared as a backup in case the non-cryogenic Castle Bravo "Shrimp" device failed to work. The test of Jughead was cancelled when the Bravo test was successful, and the cryogenic EC-16s were withdrawn and dismantled.
Castle of Castelo Branco
In 1981, structures that belonged to the GNR, and which were addorsed to the walls along the "Rua Vaz Preto" were demolished. During the course of the demolition of houses along "Rua Vaz Preto", part of the original wall and towers were re-discovered. This led to the 5 June 2009 proposal to seek a formal classification of the site's heritage status. On 26 October 2009, the DRCCentro requested the castle's classification as a "Property of Public Interest". It was accepted on 28 October by the consultative council of IGESPAR, but the process was archived on 7 January 2013, and the site never obtained its classification.
Operation Castle
As "Operation Castle" progressed, the increased yields and fallout caused test locations to be reevaluated. While the majority of the tests were planned for barges near the sand spit of Iroij, some were moved to the craters of "Bravo" and "Union". In addition, "Castle Nectar" was moved from Bikini Atoll to the crater of "Ivy Mike" at Eniwetok for expediency, since Bikini was still heavily contaminated from the previous tests.
Siege of Castelnuovo
The siege of Castelnuovo ended the failed campaign of the Holy League against the power of the Ottoman Empire in the Eastern Mediterranean. Charles V began negotiations with Barbarossa to attract him to the imperial ranks but in vain, and turned all his efforts in a great expedition against Algiers to destroy the Ottoman sea power. This expedition, known as the Journey of Algiers, ended in a disaster as a storm scattered the fleet and the army had to be reembarked having suffered heavy losses. A truce between Charles V and Suleiman the Magnificent was signed in 1543. Castelnuovo remained in Ottoman hands for almost 150 years. It was recovered in 1687, during the Morean War, by the Venetian Captain-General at sea Girolamo Cornaro, who in alliance with Montenegrins under Vuceta Bogdanovic, won a great victory over the Turks near the town and put the fortress under Venetian rule.
Dwayne Bravo
Bravo made his One Day International debut against England in their 2003/04 tour of the Caribbean, in a match in which he failed to bat but took 2–31 with the ball. In the West Indies tour of England in 2004 Bravo made his Test debut when he was selected for the First Test at Lord's in which he scored 44 and 10 and took three wickets. He finished the Test series with 68 wickets and a total of 220 runs with his most impressive performance at Old Trafford in a match in which he was the top scorer in the first innings with 77 followed by an 8 for 37 performance with the ball. The latter remains his best bowling figures in Test cricket.
Castle Bravo
Unanticipated fallout and the radiation emitted by it also affected many of the vessels and personnel involved in the test, in some cases forcing them into bunkers for several hours. In contrast to the crew of the "Lucky Dragon No. 5", who did not anticipate the hazard and therefore did not take shelter in the hold of their ship, or refrain from inhaling the fallout dust, the firing crew that triggered the explosion was able to safely shelter in their firing station when they noticed the wind was carrying the fallout in the unanticipated direction towards the island of Enyu on the Bikini Atoll where they were located, with the fire crew sheltering in place ("buttoning up") for several hours until outside radiation decayed to safer levels. "25 Roentgens per hour" was recorded above the bunker.
Rongelap Atoll
March 1, 1954: United States detonates 15-megaton hydrogen bomb (Castle Bravo test) unaware that fallout will reach Rongelap.
El Castillo del Terror (2013)
El Castillo del Terror (2013) was a professional wrestling event, the tenth annual "El Castillo del Terror" event produced by the International Wrestling Revolution Group (IWRG). IWRG has held an "Castillo del Terror" branded show since 2005, usually late in the year, making this year's event the ninth overall event in the series. The event took place on November 3, 2013, at Arena Naucalpan in Naucalpan, State of Mexico, IWRG's main arena. The main event was the eponymous "Castillo del Terror" (Spanish for "Castle of Terror") Steel cage match where the last person eliminated was forced to unmasked per the match stipulation. In the end the ten-man match saw Golden Magic defeat Alan Extreme, forcing him to unmask after the match.
Clementine (spacecraft)
Clementine (officially called the Deep Space Program Science Experiment (DSPSE)) was a joint space project between the Ballistic Missile Defense Organization (BMDO, previously the Strategic Defense Initiative Organization, or SDIO) and NASA. Launched on January 25, 1994, the objective of the mission was to test sensors and spacecraft components under extended exposure to the space environment and to make scientific observations of the Moon and the near-Earth asteroid 1620 Geographos. The Geographos observations were not made due to a malfunction in the spacecraft.
Castle Jazz Band
The band was a cooperative venture that never paid its members. It was led by banjoist Monte Ballou. The first recordings took place March 28 and April 16, 1944, and their first issue was limited to 200 copies. Wartime and employment difficulties ensured the band would not record again until 1947, but this recording was more widely distributed and garnered the nationwide attention of jazz fans and garnered critical acclaim. Ballou changed from guitar to banjo for the 1947 recording, and this, plus a change from string bass to tuba, had a significant effect on the band's sound. The most famous lineup was formed in 1948, and played music at the Jantzen Beach Amusement Park in Portland, dressed as various characters. They were regulars at the Rathskeller Cafe in 1948, and then moved to a more upscale location, the Sportsman Club, where they were a draw not only locally, but also from the traditional jazz fanbase in San Francisco. Their heyday was from 1949 to 1951. This time period included being a featured group at the 1949 Dixieland Jubilee concert, and a series of recordings on the Castle Records label that began in 1944. Trumpet player Don Kinch claimed one of these records, "Floating Down the Old Green River" sold more than a million copies. George Bruns left in 1950 to join the Turk Murphy band, and was replaced by initially by George Phillips (who had worked and recorded in the earlier edition of the band), and then by Rod Levitt.
Project 4.1
Project 4.1 was the designation for a medical study conducted by the United States of those residents of the Marshall Islands exposed to radioactive fallout from the March 1, 1954 "Castle Bravo" nuclear test at Bikini Atoll, which had an unexpectedly large yield. Government and mainstream historical sources point to the study being organized on March 6 or March 7, 1954, six days after the "Bravo" shot.
Rongelap Atoll
From 1946 through 1958 the United States military conducted numerous atmospheric nuclear weapons tests, including hydrogen bomb tests, primarily at Bikini Atoll, about from Rongelap Atoll. On March 1, 1954, the testing of the Castle Bravo hydrogen device produced an explosion that was 2½ times more powerful than predicted, and produced unexpected amounts of fallout that resulted in widespread radioactive contamination. The blast cloud contaminated more than of the surrounding Pacific Ocean including some of the then inhabited surrounding islands including Rongerik Atoll, Rongelap Atoll ( away) and Utirik Atoll.
Nuclear fusion
The latter of the two equations was unknown when the U.S. conducted the Castle Bravo fusion bomb test in 1954. Being just the second fusion bomb ever tested (and the first to use lithium), the designers of the Castle Bravo "Shrimp" had understood the usefulness of Li in tritium production, but had failed to recognize that Li fission would greatly increase the yield of the bomb. While Li has a small neutron cross-section for low neutron energies, it has a higher cross section above 5 MeV. The 15 Mt yield was 150% greater than the predicted 6 Mt and caused unexpected exposure to fallout.
Nuclear weapon design
The global alarm over radioactive fallout, which began with the Castle Bravo event, eventually drove nuclear testing literally underground. The last U.S. above-ground test took place at Johnston Island on November 4, 1962. During the next three decades, until September 23, 1992, the United States conducted an average of 2.4 underground nuclear explosions per month, all but a few at the Nevada Test Site (NTS) northwest of Las Vegas.
Bravo (software)
Bravo was the first WYSIWYG document preparation program. It provided multi-font capability using the bitmap displays on the Xerox Alto personal computer. It was produced at Xerox PARC by Butler Lampson, Charles Simonyi and colleagues in 1974.
Daigo Fukuryū Maru
The "Daigo Fukuryū Maru" encountered the fallout from the U.S. Castle Bravo nuclear test at Bikini Atoll, near the Marshall Islands, on March 1, 1954. When the test was held, the "Daigo Fukuryū Maru" was catching fish outside the danger zone that the U.S. government had declared in advance. However, the test was more than twice as powerful as predicted, and changes in weather patterns blew nuclear fallout, in the form of a fine ash, outside the danger zone. On that day, the sky in the west lit up like a sunset. Seven minutes later, the sound of the explosion arrived, with fallout reaching the ship two hours later. The fishermen attempted to escape from the area, but they took time to retrieve fishing gear from the sea, exposing themselves to radioactive fallout for several hours.
Radiophobia
This incident, due to the era of secrecy around nuclear weapons, created widespread fear of uncontrolled and unpredictable nuclear weapons, and also of radioactively contaminated fish affecting the Japanese food supply. With the publication of Joseph Rotblat's findings that the contamination caused by the fallout from the Castle Bravo test was nearly a thousand times greater than that stated officially, outcry in Japan reached such a level that the incident was dubbed by some as "a second Hiroshima". To prevent the subsequent strong anti-nuclear movement from turning into an anti-American movement, the Japanese and U.S. governments agreed on compensation of 2 million dollars for the contaminated fishery, with the surviving 22 crew men receiving about ¥ 2 million each, ($5,556 in 1954, $ in 2022)
Castle Bravo
The US Navy tanker was at Enewetak Atoll in late February 1954. "Patapsco" lacked a decontamination washdown system, and was therefore ordered on 27 February, to return to Pearl Harbor at the highest possible speed. A breakdown in her engine systems, namely a cracked cylinder liner, slowed "Patapsco" to one-third of her full speed, and when the Castle Bravo detonation took place, she was still about 180 to 195 nautical miles east of Bikini. "Patapsco" was in the range of nuclear fallout, which began landing on the ship in the mid-afternoon of 2 March. By this time "Patapsco" was 565 to 586 nautical miles from ground zero. The fallout was at first thought to be harmless and there were no radiation detectors aboard, so no decontamination measures were taken. Measurements taken after "Patapsco" had returned to Pearl Harbor suggested an exposure range of 0.18 to 0.62 R/hr. Total exposure estimates range from 3.3 R to 18 R of whole-body radiation, taking into account the effects of natural washdown from rain, and variations between above- and below-deck exposure.
Nuclear testing at Bikini Atoll
The United States was in a Cold War Nuclear arms race with the Soviet Union to build bigger and better bombs. The next series of tests over Bikini Atoll was code named Operation Castle. The first test of that series was Castle Bravo, a new design utilizing a dry fuel thermonuclear hydrogen bomb. It was detonated at dawn on March 1, 1954.
Giovanni Battista Trevano
Trevano started working in Poland around 1600. He was one of the team of architects and craftsmen who rebuilt the Royal Castle in Warsaw, on the basis of the old Gothic castle of the Masovian princes, which had already been completely remodeled by Italian architects in the second half of the sixteenth century. New work was undertaken in the years 1598-1619. He was not alone in this project: Giacomo Rodondo, Paolo del Corte and Mateo Castelli were all involved in remaking the castle into a new Baroque structure, on its imposing site along the bank of the river Vistula. The castle, much altered over the years, was bombed and dynamited by the Nazis as a symbol of Polish culture and was rebuilt in the years 1971–1988 as a national monument.
Operation Castle
Operation Castle was a United States series of high-yield (high-energy) nuclear tests by Joint Task Force 7 (JTF-7) at Bikini Atoll beginning in March 1954. It followed "Operation Upshot–Knothole" and preceded "Operation Teapot".
RaLa Experiment
On 25 July 1944 the first preliminary test was fired in the Bayo Canyon as a rehearsal, test of equipment, and measurement of collapse times and detonation and shock wave velocities. The program was delayed by about a month by late radiobarium shipments, as the test scheduled for 15 August was not conducted until mid-September. The first test with radiobarium was fired on 22 September. In late August and at the request of Rossi's group, the RaLa group was reformed under the leadership of Rossi, and Alvarez and his group took over the exploding bridgewire detonator research. At the suggestion of Robert Christy solid spheres instead of the originally intended hollow ones were chosen for the pit, in order to reduce the problems with jets and spalling. The first solid-sphere RaLa shot was performed in early December but the results were inconclusive. The shot from 14 December though, showed (in the words of Robert Bacher) "definite evidence of compression".
Daigo Fukuryū Maru
The crew suffered acute radiation syndrome (ARS) for a number of weeks after the Bravo test in March. During their ARS treatment, the crew were inadvertently infected with hepatitis C through blood transfusions. All recovered except for Aikichi Kuboyama, the boat's chief radioman, who died on September 23, 1954, from an underlying liver cirrhosis compounded by the secondary hepatitis C infection. Kuboyama is considered the first victim of the hydrogen bomb and of test shot Castle Bravo.
Nuclear testing at Bikini Atoll
The second series of tests in 1954 was codenamed Operation Castle. The first detonation, Castle Bravo, was a new design utilizing a dry fuel thermonuclear hydrogen bomb. It was detonated at dawn on March 1, 1954. Scientists miscalculated and the 15 megaton (Mt) nuclear explosion far exceeded the expected yield of 4 to 8 Mt (6 Mt predicted), and was about 1,000 times more powerful than each of the atomic bombs dropped on Hiroshima and Nagasaki during World War II. The scientists and military authorities were shocked by the size of the explosion and many of the instruments they had put in place to evaluate the effectiveness of the device were destroyed.
Combat Missions
Bravo vs Delta
Castleshaw Roman Fort
Under the supervision of the University of Manchester, further excavation was undertaken on the site in 1957–61 and 1963–64. Between 1984 and 1988, Greater Manchester Archaeological Unit undertook excavations and restoration of the site. A group led by Professor Barri Jones – an expert on Roman Britain – was set up to co-ordinate the work. North West Water, then the owners of the site, ensured the area would not be used for agriculture. In an attempt to make the site accessible to the public, the outline of the fort and fortlet was marked out in low mounds and an education centre was set up nearby. The area beyond the fort was investigated for the first time in 1995–96; archaeologists were searching for a civilian settlement or "vicus" associated with the fort. Surveys revealed a settlement triangular in shape and to the south of the fort. The "vicus" is listed as a Scheduled Ancient Monument with the fort and fortlet.
Radiation burn
The fallout produced by the Castle Bravo test was unexpectedly strong. A white snow-like dust, nicknamed by the scientists "Bikini snow" and consisting of contaminated crushed calcined coral, fell for about 12 hours upon the Rongelap Atoll, depositing a layer of up to 2 cm. Residents suffered beta burns, mostly on the backs of their necks and on their feet, and were resettled after three days. After 24–48 hours their skin was itching and burning; in a day or two the sensations subsided, to be followed after 2–3 weeks by epilation and ulcers. Darker-colored patches and raised areas appeared on their skin, blistering was uncommon. Ulcers formed dry scabs and healed. Deeper lesions, painful, weeping and ulcerated, formed on more contaminated residents; the majority healed with simple treatment. In general, the beta burns healed with some cutaneous scarring and depigmentation. Individuals who bathed and washed the fallout particles from their skin did not develop skin lesions. The fishing ship Daigo Fukuryu Maru was affected by the fallout as well; the crew suffered skin doses between 1.7–6.0 Gy, with beta burns manifesting as severe skin lesions, erythema, erosions, sometimes necrosis, and skin atrophy. 23 U.S. radar servicemen of the 28-member weather station on Rongerik were affected, experiencing discrete 1–4 mm skin lesions which healed quickly, and ridging of fingernails several months later. Sixteen crew members of the aircraft carrier USS Bairoko received beta burns and there was an increased cancer rate.
Toke Atoll
Toke Atoll was within the fallout zone of the Castle Bravo nuclear test. The degree of contamination in coconuts and coconut crabs is unknown, but levels are monitored on nearby Utirik.
Radiophobia
March 1, 1954, the operation Castle Bravo testing of a then, first of its kind, experimental thermonuclear "Shrimp" device, overshot its predicted yield of 4–6 megatons and instead produced 15 megatons; this resulted in an unanticipated amount of "Bikini snow" or visible particles of nuclear fallout being produced, fallout which caught the Japanese fishing boat the Daigo Fukuryū Maru or "Lucky Dragon" in its plume, even though it was fishing outside the initially predicted ~5 megaton fallout area which had been cordoned off for the Castle Bravo test. Approximately 2 weeks after the test and fallout exposure, the 23-member fishing crew began to fall ill, with acute radiation sickness, largely brought on by beta burns that were caused by direct contact between the "Bikini snow" fallout and their skin, through their practice of scooping the "Bikini snow" into bags with their bare hands. One member of the crew, Kuboyama Aikichi the boat's chief radioman, died 7 months later, on September 23, 1954. It was later estimated that about a hundred fishing boats were contaminated to some degree by fallout from the test. Inhabitants of the Marshall Islands were also exposed to fallout, and a number of islands had to be evacuated.
Nuclear weapons testing
Castle Bravo was the worst U.S. nuclear accident, but many of its component problems—unpredictably large yields, changing weather patterns, unexpected fallout contamination of populations and the food supply—occurred during other atmospheric nuclear weapons tests by other countries as well. Concerns over worldwide fallout rates eventually led to the Partial Test Ban Treaty in 1963, which limited signatories to underground testing. Not all countries stopped atmospheric testing, but because the United States and the Soviet Union were responsible for roughly 86% of all nuclear tests, their compliance cut the overall level substantially. France continued atmospheric testing until 1974, and China until 1980.
Castle Bravo
Castle Bravo had the greatest yield of any U.S. nuclear test, 15 Mt, though again, a substantial fraction came from fission. In the Teller–Ulam design, the fission and fusion stages were kept physically separate in a reflective cavity. The radiation from the exploding fission primary brought the fuel in the fusion secondary to critical density and pressure, setting off thermonuclear (fusion) chain reactions, which in turn set off a tertiary fissioning of the bomb's U fusion tamper and casing. Consequently, this type of bomb is also known as a "fission-fusion-fission" device. The Soviet researchers, led by Andrei Sakharov, developed and tested their first Teller–Ulam device in 1955.
Castle Bravo
The fallout spread traces of radioactive material as far as Australia, India and Japan, and even the United States and parts of Europe. Though organized as a secret test, Castle Bravo quickly became an international incident, prompting calls for a ban on the atmospheric testing of thermonuclear devices.
Lijon Eknilang
Eknilang traveled extensively throughout the United States and Europe to draw attention to the health problems experienced by Rongelap's residents due to Castle Bravo. She has been called an "icon in the Marshall Islands for her international advocacy on behalf of nuclear test victims." Eknilang spoke on behalf of the former residents of Rongelap before the United States Congress. She also spoke before the Advisory Proceedings on the Legality of the Threat or Use of Nuclear Weapons at the International Court of Justice in The Hague in November 1995.
Castle Union
Castle Union was the code name given to one of the tests in the Operation Castle series of United States nuclear tests. It was the first test of the TX-14 thermonuclear weapon (initially the "emergency capability" EC-14), one of the first deployed U.S. thermonuclear bombs.
Castle of Castelo Branco
A storm caused a landslide that destroyed the eastern/northern corner tower, leading to a formal request to the DGEMN to begin a project of restoration and lookout. Simultaneously, the municipality solicited ideas for the reconstruction of the castle from Engineer Manuel Tavares dos Santos, but lacking any funds, this project was abandoned. By 1975, the possibility of demolishing the wall along "Rua Vaz Preto" was examined: the DGEMN analyzed the walls along this corridor in 1977, in order to determine the viability, while the municipal authority expropriated homes along the segment of the walls.
Daigo Fukuryū Maru
The "Lucky Dragon No. 5" took five ocean voyages, the last of which began on January 22, 1954, and ended on March 14 of that year. The crew set off to go fishing in the Midway Sea near Midway Atoll, but when they lost most of their trawl nets to the sea, they altered their course southward near the Marshall Islands and encountered fallout from the Castle Bravo nuclear test at Bikini Atoll on March 1.
Nuclear fallout
Parts of the sea bottom may become fallout. After the Castle Bravo test, white dust—contaminated calcium oxide particles originating from pulverized and calcined corals—fell for several hours, causing beta burns and radiation exposure to the inhabitants of the nearby atolls and the crew of the "Daigo Fukuryū Maru" fishing boat. The scientists called the fallout "Bikini snow".
Mark 22 nuclear bomb
The Mark 22 nuclear bomb (Mk-22) was the first thermonuclear device test by the University of California Radiation Lab (UCRL). The test was part of the "Koon" shot of Operation Castle. The Mk-22 failed to achieve anything like its intended yield due to premature heating of the secondary from exposure to neutrons. As the other UCRL test planned for the Castle series, the liquid fueled "Ramrod" device had the same basic design flaw, that test was canceled. Within a month of the bomb’s failure, the Mk-22 was terminated because the United States Atomic Energy Commission realized there was nothing that could be done to salvage the design.
Castle Bravo
Sir Joseph Rotblat, working at St Bartholomew's Hospital, London, demonstrated that the contamination caused by the fallout from the test was far greater than that stated officially. Rotblat was able to deduce that the bomb had three stages and showed that the fission phase at the end of the explosion increased the amount of radioactivity a thousandfold. Rotblat's paper was taken up by the media, and the outcry in Japan reached such a level that diplomatic relations became strained and the incident was even dubbed by some as a "second Hiroshima". Nevertheless, the Japanese and US governments quickly reached a political settlement, with the transfer to Japan of $15.3 million as compensation, with the surviving victims receiving about 2 million each ($5,550 in 1954, or about $ in 2022). It was also agreed that the victims would not be given Hibakusha status.
Mark 16 nuclear bomb
The planned test of the TX-16 bomb in the Castle Yankee test of Operation Castle was canceled due to the spectacular success of the "Shrimp" device in the Castle Bravo test.
Pacific Proving Grounds
Because of the large amount of atmospheric testing, and especially the Castle Bravo accident of 1954, many of the islands which were part of the Pacific Proving Grounds are still contaminated by nuclear fallout. Many of the island inhabitants at the time of testing suffered from increased incidence of various types of cancers and birth defects.
Castle Romeo
It was detonated on March 27, 1954, after several delays (which played havoc with the planned experimental measurements program) at Bikini Atoll of the Marshall Islands, on a barge moored in the middle of the crater from the Castle Bravo test. It was the first such barge-based test, a necessity that had come about because the powerful thermonuclear devices completely obliterated the small islands following detonation.
Castle Bravo
In terms of TNT equivalence, "Castle Bravo" was about 1,000 times more powerful than each of the atomic bombs that were dropped on Hiroshima and Nagasaki during World War II. "Castle Bravo" is the fifth largest nuclear explosion in history, exceeded by the Soviet tests of "Tsar Bomba" at approximately 50 Mt, "Test 219" at 24.2 Mt, and two other ~20 Mt Soviet tests in 1962 at Novaya Zemlya.
Castle Bravo
The Soviet Union had previously used lithium deuteride in its Sloika design (known as the "Joe-4" in the U.S.), in 1953. It was not a true hydrogen bomb; fusion provided only 15–20% of its yield, most coming from boosted fission reactions. Its yield was 400 kilotons, and it could not be infinitely scaled, as with a true thermonuclear device.