Castle Bravo

Castle Bravo
Film of the Bravo detonation and subsequent mushroom cloud
Castle Bravo is located in Pacific Ocean
Castle Bravo
Location within Pacific Ocean
Information
CountryUnited States
Test seriesOperation Castle
Test siteBikini Atoll
Coordinates11°41′50″N 165°16′19″E / 11.69722°N 165.27194°E / 11.69722; 165.27194
DateMarch 1, 1954; 70 years ago (1954-03-01)
Test typeAtmospheric
Yield15 megatons of TNT (63 PJ)
Test chronology

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.[1][2] 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,[3] which led to radioactive contamination in the surrounding area.[4]

Fallout, the heaviest of which was in the form of pulverized surface coral from the detonation, fell on residents of Rongelap and Utirik atolls, while the more particulate and gaseous fallout spread around the world. The inhabitants of the islands were evacuated only three days later and suffered radiation sickness. Twenty-three crew members of the Japanese fishing vessel Daigo Fukuryū Maru ("Lucky Dragon No. 5") were also contaminated by the heavy fallout, experiencing acute radiation syndrome, including the death six months later of Kuboyama Aikichi, the boat's chief radioman. The blast incited a strong international reaction over atmospheric thermonuclear testing.[5]

The Bravo Crater is located at 11°41′50″N 165°16′19″E / 11.69722°N 165.27194°E / 11.69722; 165.27194. The remains of the Castle Bravo causeway are at 11°42′6″N 165°17′7″E / 11.70167°N 165.28528°E / 11.70167; 165.28528.

  1. ^ "Operation Castle". nuclearweaponarchive.org. Retrieved September 23, 2017.
  2. ^ Rowberry, Ariana (November 30, 2001). "Castle Bravo: The Largest U.S. Nuclear Explosion". Brookings Institution. Retrieved September 23, 2017.
  3. ^ "Operation Castle". nuclearweaponarchive.org. May 17, 2006. Retrieved May 20, 2016.
  4. ^ Hughes EW; Molina MR; Abella MKIL; Nikolić-Hughes I; Ruderman MA (July 30, 2019). "Radiation maps of ocean sediment from the Castle Bravo crater". Proceedings of the National Academy of Sciences. 116 (31): 15420–15424. Bibcode:2019PNAS..11615420H. doi:10.1073/pnas.1903478116. PMC 6681739. PMID 31308235.
  5. ^ Foster, John Bellamy (2009). The Ecological Revolution: Making Peace with the Planet. Monthly Review Press. p. 73.