Castle Union
1954 CE.
Shown on the map at 11.666°, 165.387°.
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 26 April 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.
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