JUNE 3, 1965: Astronaut Ed White becomes the first American to walk in space, spending 20 minutes outside of the Gemini 4 space capsule as it orbited 120 miles above the Earth. With fellow astronaut James McDivitt inside, White floated outside attached to a tether, using a hand-held propulsion unit to briefly maneuver. Finally ordered to return, he quipped: “I’m coming back in … and it’s the saddest moment of my life.” White was killed two years later when a fire swept through the Apollo 1 spacecraft during launchpad testing.