World Aviation and Cosmonautics Day was obseved on __________.

World Aviation and Cosmonautics Day, a date to honour the first ever flight of a human in space.On April 12,1961, Soviet cosmonaut Yuri Gagarin carried out the famous flight in spacecraft Vostok 1 started from Baikonur Cosmodrome. In November 1968, the 61st General Conference of the Federation Aeronautique Internationale (FAI), known as the World Air sports Federation, decided to celebrate World Aviation and Cosmonautics Day on April 12. Many countries organize a Yuri's Night on April 12. The first Yuri's Night was celebrated on the 40th anniversary of the first manned flight into space in 2001.