April 12, 2011 marks the 50th anniversary of Soviet cosmonaut Yuri Gagarin's journey into outer space which revolutionized the history of space research and of the human race as a whole.

The historic expedition started in April 1961 when Gagarin became the first human to travel into space and the first to orbit the earth aboard the USSR's Vostok-1. The Vostok spacecraft was designed to carry only a single cosmonaut.

After the flight, Gagarin became an instant celebrity, touring different corners of the world like Japan, Italy, Germany, Canada and Brazil. He was even invited by the Queen of England to have tea at the Buckingham Palace.

However, on March 27, 1968, Yuri died in a plane crash while on a routine training flight from Chkalovsky Air Base in Moscow Oblast, Russia.

A series of tributes around the world coincided with the 50th anniversary of Gagarin's journey into outer space. A film entitled First Orbit was created containing footage from the International Space Station. Google, on the other hand, celebrated Gagarin's feat by a Google Doodle on its global homepage.

A special video message was also issued by the Expedition 27 crew aboard the International Space Station wishing the world a Happy Yuri's Night on the occasion.

Start the slideshow to get an exclusive glimpse of the cosmonaut and the 50th anniversary celebrations: