International day of Human space The International Day of Human Space Flight is celebrated on April 12th each year. It marks the anniversary of the first human space flight, which was made by Yuri Gagarin on April 12, 1961. The day is intended to celebrate the achievements of human space exploration and to promote the peaceful use of outer space for the benefit of all humanity. The International Day of Human Space Flight is celebrated on April 12th each year. It marks the anniversary of the first human space flight, which was made by Yuri Gagarin on April 12, 1961. The day is intended to celebrate the achievements of human space exploration and to promote the peaceful use of outer space for the benefit of all humanity. The United Nations General Assembly declared April 12 as the International Day of Human Space Flight in 2011 to recognize the contributions of space science and technology to the betterment of the human condition. The day is also meant to encourage inter...