Johnston Atoll

[[File:Contaminated Johnston Island Launch Emplacement 1, Bluegill Prime, Thor failure, July 25, 1962..jpg|thumb|Johnston Island Launch Emplacement One (LE1) after a Thor missile launch failure and explosion contaminated the island with plutonium during the Operation "Bluegill Prime" nuclear test, July 1962]]

[[File:Contaminated Johnston Island Launch Emplacement 1, Bluegill Prime, Thor failure, July 25, 1962..jpg|thumb|Johnston Island Launch Emplacement One (LE1) after a Thor missile launch failure and explosion contaminated the island with plutonium during the Operation "Bluegill Prime" nuclear test, July 1962]]

"[[Operation Fishbowl#Starfish|Starfish]]", a high altitude Thor launched nuclear test scheduled for June 20, 1962, was the first to contaminate the atoll. The rocket with the 1.45-megaton Starfish device (W49 warhead and the [[W76|MK-4]] [[Atmospheric entry|re-entry vehicle]]) on its nose was launched that evening, but the Thor missile engine cut out only 59 seconds after launch. The range safety officer sent a destruct signal 65 seconds after launch, and the missile was destroyed at approximately {{convert|10.6|km|abbr=off|sp=us}} altitude—the warhead high explosive detonated in a 1-point safe fashion, destroying the warhead without producing nuclear yield. Large pieces of the plutonium-contaminated missile, including fragments of the warhead, booster rocket, engine, re-entry vehicle, and missile parts, fell back on Johnston Island. More wreckage, along with plutonium contamination, was found on nearby Sand Island.

"[[Operation Fishbowl#Starfish|Starfish]]", a high altitude Thor launched nuclear test scheduled for June 20, 1962, was the first to contaminate the atoll. The rocket with the 1.45-megaton Starfish device (W49 warhead in the MK-4 [[Atmospheric entry|re-entry vehicle]]) on its nose was launched that evening, but the Thor missile engine cut out only 59 seconds after launch. The range safety officer sent a destruct signal 65 seconds after launch, and the missile was destroyed at approximately {{convert|10.6|km|abbr=off|sp=us}} altitude—the warhead high explosive detonated in a 1-point safe fashion, destroying the warhead without producing nuclear yield. Large pieces of the plutonium-contaminated missile, including fragments of the warhead, booster rocket, engine, re-entry vehicle, and missile parts, fell back on Johnston Island. More wreckage, along with plutonium contamination, was found on nearby Sand Island.

"[[Operation Fishbowl#Bluegill Prime|Bluegill Prime]]," the second attempt to launch the payload, which failed last time, was scheduled for 23:15 (local) on July 25, 1962. It, too, was a genuine disaster and caused the most severe plutonium contamination on the island. The Thor missile carried one pod, two re-entry vehicles, and the [[W50 (nuclear warhead)|W50]] nuclear warhead. The missile engine malfunctioned immediately after ignition, and the range safety officer fired the destruct system while the missile was still on the launch pad. The Johnston Island launch complex was demolished in the subsequent explosions and fire, which burned through the night. The launch emplacement and portions of the island were contaminated with radioactive plutonium spread by the blast, fire, and wind-blown smoke.

"[[Operation Fishbowl#Bluegill Prime|Bluegill Prime]]," the second attempt to launch the payload, which failed last time, was scheduled for 23:15 (local) on July 25, 1962. It, too, was a genuine disaster and caused the most severe plutonium contamination on the island. The Thor missile carried one pod, two re-entry vehicles, and the [[W50 (nuclear warhead)|W50]] nuclear warhead. The missile engine malfunctioned immediately after ignition, and the range safety officer fired the destruct system while the missile was still on the launch pad. The Johnston Island launch complex was demolished in the subsequent explosions and fire, which burned through the night. The launch emplacement and portions of the island were contaminated with radioactive plutonium spread by the blast, fire, and wind-blown smoke.