This represents the 7 most powerful nuclear weapons tests by the Superpowers during the Cold War.
At remote locations in the South Pacific at Bikini Atoll and the Novaya Zemlya archipelago in the Artic Ocean, the USSR and US of A tested higher and higher megaton yield nukes at the peak of the arms race
The largest, a hydrogen bomb tested by Russia, was known as Tsar Bomba (also rds-220 and big ivan).
At 58 megatons, the equivalent of 58 million cubic tons of TNT, it was 1400 times the explosive force of Hiroshima - against which all the explosions in the above graphic are bench-marked.
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