Yuri's Night
It is named for the first human to launch into space , Yuri Gagarin , who flew the Vostok 1 spaceship on April 12 , 1961 . 
<triplet> Yuri Gagarin <subj> Vostok 1 <obj> astronaut mission <triplet> Vostok 1 <subj> Yuri Gagarin <obj> crew member <subj> April 12, 1961 <obj> time of spacecraft landing