Yuri Gagarin aboard Vostok 1Soviet cosmonaut Yuri Gagarin, the first human space traveler, dies along with a flight instructor in a MiG jet fighter crash. Considered too valuable a publicity asset to risk in another spaceflight, Gagarin had been barred from any further space missions. Several investigations into the fatal crash are conducted, with none of them reaching any definitive conclusions, though unfavorable flying weather and a sudden dive (possibly also a result of the weather) are commonly cited factors. Gagarin’s ashes are buried in the wall of the Kremlin.