Castle Union | |
---|---|
Information | |
Country | United States |
Test series | Operation Castle |
Test site | Bikini Atoll |
Date | April 26, 1954 |
Test type | Atmospheric |
Yield | 6.9 megatons of TNT |
Test chronology | |
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.
An "Alarm Clock" device is a "dry" fusion bomb, using lithium deuteride fuel for the fusion stage of a "staged" fusion bomb, unlike the cryogenic liquid deuterium of the first-generation Ivy Mike fusion device.
It differed from the Castle Romeo "Runt" device, tested shortly before, in using highly enriched lithium (approximately 95% lithium-6; natural lithium is a mixture of lithium-6 and lithium-7 isotopes). The "Runt" device had 7.5% lithium-6 in the fusion fuel.
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 roughly double the predicted 3-4 megatons. Although the barge had been moored in over 160 feet (49 m) of water, the test left a crater 3,000 feet (910 m) in diameter and 90 feet (27 m) deep in the bottom of the lagoon.
Like the Ivy Mike, Castle Bravo, and Castle Romeo tests, a large percentage of the yield was produced by fast fission of the natural uranium tamper, which contributed to the extensive fallout caused by these tests.
As the highly enriched lithium was both expensive and scarce at the time, it limited the number of these weapons that could be produced. The "Runt" design tested in Castle Romeo and Castle Yankee was preferred for deployment.
Nuclear weapon designs are physical, chemical, and engineering arrangements that cause the physics package of a nuclear weapon to detonate. There are three existing basic design types:
Operation Ivy was the eighth series of American nuclear tests, coming after Tumbler-Snapper and before Upshot–Knothole. The two explosions were staged in late 1952 at Enewetak Atoll in the Pacific Proving Ground in the Marshall Islands.
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.
Operation Greenhouse was the fifth American nuclear test series, the second conducted in 1951 and the first to test principles that would lead to developing thermonuclear weapons. Conducted at the new Pacific Proving Ground, on islands of the Enewetak Atoll, it mounted the devices on large steel towers to simulate air bursts. This series of nuclear weapons tests was preceded by Operation Ranger and succeeded by Operation Buster-Jangle.
Operation Upshot–Knothole was a series of eleven nuclear test shots conducted in 1953 at the Nevada Test Site. It followed Operation Ivy and preceded Operation Castle.
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 remains the most powerful nuclear device ever detonated by the United States and the first lithium deuteride-fueled thermonuclear weapon tested using the Teller-Ulam design. Castle Bravo's yield was 15 megatons of TNT [Mt] (63 PJ), 2.5 times the predicted 6 Mt (25 PJ), due to unforeseen additional reactions involving lithium-7, which led to radioactive contamination in the surrounding area.
Ivy Mike was the codename given to the first full-scale test of a thermonuclear device, in which part of the explosive yield comes from nuclear fusion. Ivy Mike was detonated on November 1, 1952, by the United States on the island of Elugelab in Enewetak Atoll, in the now independent island nation of the Marshall Islands, as part of Operation Ivy. It was the first full test of the Teller–Ulam design, a staged fusion device.
Elugelab, or Elugelap, was an island, part of the Enewetak Atoll in the Marshall Islands. It was destroyed by the world's first true hydrogen bomb test on 1 November 1952, a test which was codenamed shot "Mike" of Operation Ivy. Prior to being destroyed, the island was described as "just another small naked island of the atoll".
RDS-37 was the Soviet Union's first two-stage hydrogen bomb, first tested on 22 November 1955. The weapon had a nominal yield of approximately 3 megatons. It was scaled down to 1.6 megatons for the live test.
Castle Yankee was the code name given to one of the tests in the Operation Castle series of American tests of thermonuclear bombs. It was originally intended as a test of a TX-16/EC-16 Jughead bomb, but the design became obsolete after the Castle Bravo test was successful. The test device was replaced with a TX-24/EC-24 Runt II bomb which was detonated on May 5, 1954, at Bikini Atoll. It released energy equivalent to 13.5 megatons of TNT, the second-largest yield ever in a U.S. fusion weapon test.
Castle Romeo was the code name given to one of the tests in the Operation Castle series of U.S. nuclear tests. It was the first test of the TX-17 thermonuclear weapon, the first deployed thermonuclear bomb.
A thermonuclear weapon, fusion weapon or hydrogen bomb (H bomb) is a second-generation nuclear weapon design. Its greater sophistication affords it vastly greater destructive power than first-generation nuclear bombs, a more compact size, a lower mass, or a combination of these benefits. Characteristics of nuclear fusion reactions make possible the use of non-fissile depleted uranium as the weapon's main fuel, thus allowing more efficient use of scarce fissile material such as uranium-235 or plutonium-239. The first full-scale thermonuclear test was carried out by the United States in 1952 and the concept has since been employed by most of the world's nuclear powers in the design of their weapons.
The Teller–Ulam design is a technical concept behind modern thermonuclear weapons, also known as hydrogen bombs. The design – the details of which are military secrets and known to only a handful of major nations – is believed to be used in virtually all modern nuclear weapons that make up the arsenals of the major nuclear powers.
The Mark 24 nuclear bomb was an American thermonuclear bomb design, based on the third American thermonuclear bomb test, Castle Yankee. The Mark 24 bomb was tied as the largest weight and size nuclear bomb ever deployed by the United States, with the same size and weight as the Mark 17 nuclear bomb which used a very similar design concept but unenriched Lithium.
Canopus was the codename of the first French two-stage thermonuclear test. It was conducted by the Pacific Carrier Battle Group on 24 August 1968, at the Pacific Experiments Centre near Fangataufa atoll, French Polynesia. The test made France the fifth country to test a thermonuclear device after the United States, the Soviet Union, the United Kingdom and China.
The Mark 14 nuclear bomb was a 1950s strategic thermonuclear weapon, the first deployed solid-fuel hydrogen bomb. It was an experimental design, and only five units were produced in early 1954. It was tested in April 1954 during the Castle Union nuclear test and had a yield of 6.9 Mt. The bomb is often listed as the TX-14 or EC-14. It has also been referred to as the "Alarm Clock" device though it has nothing to do with the design by the same name proposed earlier by Edward Teller and known as the Sloika in the Soviet Union.
The Mark 16 nuclear bomb was a large thermonuclear bomb, based on the design of the Ivy Mike, the first thermonuclear device ever test fired. The Mark 16 is more properly designated TX-16/EC-16 as it only existed in Experimental/Emergency Capability (EC) versions.
Orange Herald was a British nuclear weapon, tested on 31 May 1957. At the time it was reported as an H-bomb, although in fact it was a large boosted fission weapon and remains to date, the largest fission device ever detonated.
Operation Redwing was a United States series of 17 nuclear test detonations from May to July 1956. They were conducted at Bikini and Enewetak atolls by Joint Task Force 7 (JTF7). The entire operation followed Project 56 and preceded Project 57. The primary intention was to test new, second-generation thermonuclear weapons. Also tested were fission devices intended to be used as primaries for thermonuclear weapons, and small tactical weapons for air defense. Redwing demonstrated the first United States airdrop of a deliverable hydrogen bomb during test Cherokee. Because the yields for many tests at Operation Castle in 1954 were dramatically higher than predictions, Redwing was conducted using an "energy budget": There were limits to the total amount of energy released, and the amount of fission yield was also strictly controlled. Fission, primarily "fast" fission of the natural uranium tamper surrounding the fusion capsule, greatly increases the yield of thermonuclear devices, and constitutes the great majority of the fallout, as nuclear fusion is a relatively clean reaction.
The Mk 36 was a heavy high-yield nuclear bomb developed by the United States during the 1950s. It was a thermonuclear, using a multi-stage fusion secondary system to generate yields up to about 10 megatons TNT equivalent.