The first nuclear device was detonated as a test by the United States at the Trinity site (Alamogordo, New Mexico) on July 16, 1945, with a yield approximately equivalent to 20 kilotons of TNT. The first thermonuclear weapon technology device, code-named "Mike", was tested at the Enewetak atoll in the Marshall Islands on November 1, 1952 (local date), also by the United States.

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