This Animated GiF file courtesy of Elena Filatova ©

This was the first thermonuclear device built upon the Teller-Ulam principles of staged radiation implosion. The device was designed by the Panda Committee directed by J. Carson Mark at Los Alamos (Edward Teller declined to play a role in its development). The enormous explosion was the 4th largest device ever tested by the U.S. The island the test device was installed on, Elugelab (code named Flora), was entirely destroyed. The resulting crater was 6240 ft across and 164 ft deep. High levels of radiation blanketed much of the atoll following the test.
Ivy Mike
19:14:59.4 31 October 1952 (GMT) 07:14:59.4 1 November 1952 (local)
Elugelab ("Flora") Island, Enewetak Atoll
Surface burst 10.4 Mt

Mike was a "two stage" device and had a yield of 10.4 megatons. The primary stage was a TX-5 fission bomb, the secondary stage consisted of liquid deuterium fusion fuel stored in a cylindrical Dewar (thermos) flask. Running down the center of the Dewar was a plutonium "spark plug" rod to ignite the fusion reaction. The Dewar was surrounded by a natural uranium pusher/tamper weighing more than 5 metric tons. The entire assembly was housed in an enormous steel casing, 80 inches wide and 244 inches long, with walls ~10-12 inches thick, the largest single forging made up to that time. The inside surface of the casing was lined with sheets of lead and polyethylene to form the radiation channel that conducted heat from the primary to the secondary. The entire device weighed 82 tons.

Enewetak Atoll, before Ivy Mike

Enewetak Atoll, after Ivy Mike


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