Before astronauts could land and walk on the Moon, NASA had to be sure they could do three things: live in space for days at a time, catch and link up with other spacecraft, and work outside their ship. And it took stabs at two of those goals 60 years ago today, with a mission called Gemini 4.

  [AUDIO: 3, 2, 1, Ignition … Liftoff …]

Astronauts James McDivitt and Ed White were scheduled to spend four days in space. That was longer than the first seven American missions combined.

And White would make the first American spacewalk. He’d float outside the cabin for a few minutes, using a small “gun” of compressed air to move around.

And three and a half hours after launch, it was time to get started:

CAPCOM: Gemini 4, Hawaii capcom. We just had word from Houston, we’re ready to have you get out   whenever you’re ready. Okay, my feet are out. … Okay, I’m out.

The spacewalk went well – very well. [WHITE: I feel like a million dollars!] In fact, it went so well that White didn’t want it to end.

HOUSTON: The flight director says get back in!

     McDIVITT: This is Jim, you got any message for us?

     CAPCOM: Gemini 4, get back in!

     McDIVITT: Okay…

Actually working during a spacewalk turned out to be a lot harder than White had made it look. It took several more missions to work out the kinks. But the success of Gemini 4 helped make it possible for astronauts to walk on the Moon just four years later.

Script by Damond Benningfield