BIKINI ATOLL HYDROGEN BOMB TEST 1946 POSTER

Hydrogen Bomb Test Baker, on 25 July 1946, an underwater nuclear detonation, was, according to the Task Force history, “a giant and unprecedented spectacle.” It produced a huge column of a million tons of water over a mile high, and 80 to 100 waves spread radioactive fallout on nearby ships, partly through rain and partly through a “moving column of radioactive mist.” The column of water lifted the battleship Arkansas before plunging it into the lagoon. Nine ships eventually sank, including another battleship and an aircraft carrier. But the most serious damage was unseen. According to the initial report by the JCS Evaluation Board, the radioactive hazard produced by the spread of water was so dangerous that “after 4 days it was still unsafe for inspection parties operating within a well-established safety margin, to spend any useful length of time at the centre of the target area or to board ships anchored there.” Of the test animals in the target ships, all of the pigs died within a month. Even though military experts had predicted the spread of radioactivity months before, its intensity came as a surprise.