On Aug. 30, 1961, the Soviet Union announced that it would end a three-year moratorium on high-altitude nuclear testing. The U.S. response was a well-documented series of five tests in 1962 called Operation Fishbowl. One of those tests, the Starfish Prime project, launched on July 9 and successfully detonated at an altitude of about 250 miles, producing a yield equivalent to approximately 1.4 megatons of TNT.
The explosion resulted in an EMP much larger than anticipated, illuminating a large area of the Pacific Ocean, causing electrical damage in Hawaii some 900 miles away from the detonation point, trapping high-energy electrons to form radiation belts around the earth, disabling one-third of satellites in low earth orbit and causing other satellites to fail over time.
Much less documented were the effects of six high-altitude nuclear tests conducted by the U.S. in 1958. The official explanation for the lack of data released from those tests, as published in the U.S. Government Project Officer’s Interim Report on the Starfish Prime project, is that the tests were poorly instrumented and hastily executed, and that the models of the bursts were too uncertain to produce reliable results.
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Do you think there is more to this story than meets the eye? If the government has more information on the EMP effects of the 1958 tests, why has it not been made available as the results from the 1962 tests have been? Chime in with your opinion in the comments.