Sixty years ago, on March 1, 1954, a Japanese fishing boat named Lucky Dragon No. 5 was doused by radioactive fallout from a U.S. hydrogen-bomb test, codenamed Castle Bravo, on Bikini Atoll in the Marshall Islands. Although the bomb was over 1,000 times more powerful than the one dropped on Hiroshima in August 1945, Bravo was just one of 67 nuclear tests the U.S. conducted in that part of the North Pacific between 1946-58, rendering some atolls uninhabitable.
On the morning of the test, the wind blew radioactive fallout onto unlucky islanders, American servicemen and that Japanese boat fishing for tuna 160 km east of the blast site, some 32 km outside the exclusion zone. The crew reported that sandy ash fell onto the vessel for a few hours, and soon after they began to suffer nausea. By the time they returned to their home port of Yaizu in Shizuoka Prefecture on March 14, they had serious symptoms of radiation sickness and were hospitalized in Tokyo. The radio operator died six months later with American doctors insisting fallout was not the cause — a finding that Japanese doctors disputed.