“Operation Hardtack’s Redstone Launched High-Altitude Nuclear Detonations and the Unanticipated Discovery of the High-Altitude Electromagnetic Pulse (EMP) Effect” by
Edgar J. Manton
Quest Volume: 28 #3 (2021)
In 1958, the Redstone Arsenal’s Army Ballistic Missile Agency launched two Redstone rockets from Johnston Island in the Pacific. They carried two thermonuclear devices for detonation in the ionosphere. These were the first US tests of megaton nuclear devices conducted at high altitudes. Their purpose was to study the blast, flash, and immediate radiation effects of a nuclear burst in the high atmosphere and compare them to the effects of surface nuclear bursts. In addition, they were to determine whether such explosions could deter nuclear warheads delivered by an enemy ICBM. Furthermore, the electromagnetic pulse (EMP) generated was to be evaluated to determine whether this pulse could be used to detect secret high-altitude bursts conducted by other nations. The high-altitude nuclear burst effects were observed to differ significantly from a surface burst due to the lack of atmosphere at high elevations. In addition, initial evidence was provided of the ineffectiveness of high-altitude nuclear bursts in damaging enemy nuclear warheads. However, the tremendous strength of the nuclear EMP generated at the high elevations was a complete and unexpected surprise. These nuclear bursts identified the need to further study the high-altitude EMP phenomenon, which subsequently has been determined to pose a potentially major threat to the United States.
Manton, Edgar J. “Operation Hardtack’s Redstone Launched High-Altitude Nuclear Detonations and the Unanticipated Discovery of the High-Altitude Electromagnetic Pulse (EMP) Effect.” Quest: The History of Spaceflight Quarterly 28, no. 3 (2021): 23-42.