Canopus

Canopus (or Opération Canopus) was the codename of the first French two-stage thermonuclear test. It was conducted by the Pacific Carrier Battle Group (nicknamed Alfa Force) on 24 August 1968, at the Pacific Experiments Centre near Fangataufa atoll, French Polynesia. The test made France the fifth country to test a thermonuclear device after the United States, the Soviet Union, the United Kingdom and China.