|Test site||Pacific Proving Grounds|
|Number of tests||2|
|Test type||Atmospheric tests|
|Device type||Thermonuclear (Mike)
|Max. yield||10.4 Mt|
|Previous test||Operation Tumbler-Snapper|
|Next test||Operation Upshot-Knothole|
Operation Ivy was the eighth series of American nuclear tests, coming after Tumbler-Snapper and before Upshot-Knothole. Its purpose was to help upgrade the U.S. arsenal of nuclear weapons in response to the Soviet nuclear weapons program. The two explosions were staged in late 1952 at Eniwetok Atoll in the Pacific Proving Ground in the Marshall Islands.
The first Ivy shot, Mike, was the first successful full-scale test of a multi-megaton thermonuclear weapon ("hydrogen bomb") using the Teller-Ulam design. Unlike later thermonuclear weapons, Mike used deuterium as its fusion fuel, maintained as a liquid by an expensive and cumbersome cryogenic system. It was detonated on Elugelab Island yielding 10.4 megatons, almost 500 times the yield of the bomb dropped on Nagasaki. Eight megatons of the yield was from fast fission of the uranium tamper, creating massive amounts of radioactive fallout. The detonation left an underwater crater 6,240 ft (1.9 km) wide and 164 ft (50 m) deep where Elugelab Island had been. Following this successful test, the Mike design was weaponized as the EC-16, but it was quickly abandoned for solid-fueled designs after the success of the Castle Bravo shot.
The second test, King, fired the largest nuclear weapon to date using only nuclear fission (no fusion nor fusion boosting). This "Super Oralloy Bomb" was intended as a backup if the fusion weapon failed. King yielded 500 kilotons, 25 times more powerful than the Fat Man weapon.
|Name||Date, Time (UT)||Location||Elevation + Height||Delivery||Purpose||Device||Yield||Notes|
|Mike||31 October 1952 19:14:59.4||Elugelab ("Flora") Island, Enewetok||2 metres (6 ft 7 in) + 8 metres (26 ft)||surface||weapon development||TX-16||10.4–12 megatons||First Teller-Ulam design hydrogen bomb; cryogenic deuterium fuel; Elugelab completely erased.|
|King||15 November 1952 23:30:00.0||2,000 feet (610 m) north of Runit ("Yvonne") Island, Enewetok||0 + 450 metres (1,480 ft)||free airdrop||weapon development||Mark 18f||500 kilotons||Largest pure-fission bomb; nicknamed the SOB, for SuperOralloy Bomb.|
- Chuck Hansen, U. S. Nuclear Weapons: The Secret History (Arlington: AeroFax, 1988)
- United States Nuclear Tests: July 1945 through September 1992 (Revision 15). Department of Energy, Nevada Operations Office. December 2000. Retrieved 10/26/2013.
- Yang, Xiaoping, Robert North, and Carl Romney (August 2000). CMR Nuclear Explosion Database (Revision 3). SMDC Monitoring Research. Retrieved 10/26/2013.
- Hansen, Chuck (1995). The Swords of Armageddon, Vol. 8. Chukelea Publications (Sunnyvale, CA). ISBN 978-0-9791915-1-0.
- "Into the Mushroom Cloud | History of Flight | Air & Space Magazine". airspacemag.com. Retrieved 2012-11-01.
- Michael Robert Patterson. "Jimmy Priestly Robinson, Captain, United States Air Force". arlingtoncemetery.net. Retrieved 2012-11-01.
- Local time (MHT) is 12 hours later than UT; local date is one day after UT if UT time is on or after 12:00.
|Wikimedia Commons has media related to Operation Ivy.|
- Curtiss Atomic Marines
- Operation Ivy
- Analysis of Radiation Exposure for Navy Personnel at Operation Ivy
- The short film Operation IVY is available for free download at the Internet Archive [more] formerly classified
- The short film Operation Ivy (1952) is available for free download at the Internet Archive [more] formerly unclassified, for civil defense