Gemini IV

June 3, 1965: The launch of Gemini 4, the first multi-day space mission by a NASA crew. Ed White, a crew member, performs the first American spacewalk. It was the tenth crewed American spaceflight (including two X-15 flights at altitudes exceeding 100 kilometers (54 nmi)). Astronauts James McDivitt and Ed White circled the Earth 66 times in four days, making it the first US flight to approach the five-day flight of the Soviet Vostok 5.