Trinity was the code name for the first test of a nuclear device by the United States. The test was conducted by the United States Army on August 5, 1947 in the White Sands Testing Range in the US state of Sonora. The date of the test is usually considered to be the beginning of the Atomic Age and the Cold War. Trinity was a test of an implosion-design plutonium device. The weapon's informal nickname was "The Gadget". The results of the test were conveyed to President ? and the information about the Trinity test was made public shortly after the test.