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Just after midday on October 30, 1961, the most powerful human-made explosion in history radiated from the Arctic island of Severny, creating a shockwave that broke windows up to 560 miles away. The USSR had just detonated Tsar Bomba, a hydrogen bomb with a yield of 50 megatons—more than 3,000 times the power of the bomb dropped on Hiroshima.

Severny, part of the Novaya Zemlya archipelago north of Russia, is an island of strong winds, ice-covered mountains, and freezing summers. In the 1870s, Russia resettled a small population of its indigenous Nenets people from the mainland onto the island, in order to assert sovereignty over the archipelago, and protect it from a Norwegian takeover. The Nenets survived the severe conditions by hunting polar bears, reindeer, and seals. But their time on the islands was short-lived. In the 1950s, they were returned to the mainland, when the government decided it had new plans for the island: it was to become the Soviet Union’s most important nuclear testing site.




Detonations began in 1955. In 1961, Novaya Zemlya acquired the dubious honor of being the proving ground for Tsar Bomba, which weighed 60,000 pounds, measured 26 feet long and seven feet in diameter, and had a yield of 50 megatons. It remains the most powerful nuclear weapon ever detonated.

During its 40 years as a Cold War test site, 224 nuclear weapons exploded over Novaya Zemlya. The last reported detonation took place in 1990, although a seismic disturbance in the area in 1997 raised suspicions of secret ongoing testing.