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1952 - First test of US hydrogen bomb
With a code-name of ‘’Ivy Mike’’, the US detonates their first full-scale hydrogen bomb on the island of Elugelab, one of the Marshall Islands in the Pacific Ocean. As a thermonuclear weapon that utilises energy from nuclear fission reactions, the explosive power of this bomb is unparalleled. The fireball created by Ivy Mike reached 5.2km wide, released 10 megatons of TNT, and left a huge crater where Elugelab had once been. The bomb was 1,000 times more powerful than the one dropped on Hiroshima, Japan, in 1945 but was never intended as a deliverable weapon. It was strictly experimental, providing a platform from which the US could further develop their understanding and potential use of hydrogen bombs.
1884 - Greenwich Mean Time (GMT) adopted universally
The International Meridian Conference in Washington, USA, delineates the Greenwich Mean Time (GMT) over 24 time zones across the world. Prior to the late 1800s there were several prime meridians used for longitudinal references, but the Royal Observatory in Greenwich, UK, was eventually chosen due to its reputation for its reliability and accuracy in publishing data. Britain also had more ships using this time than the rest of the world combined. Despite this global recognition, the French continued to treat Paris as the prime meridian until 1911, and did not formally use GMT as a reference to its standard time zone until 1978.
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