Building on the success of the first piloted Gemini mission, NASA prepared to launch its most ambitions flight to date – Gemini IV. During June 1965, two astronauts would not only stay in orbit four days, one would attempt America’s first spacewalk. It was another example of advancing technology enabling new avenues of exploration. Since the Soviet Union launched the world’s first satellite, Sputnik 1, in Oct. 4, 1957, the United States had been attempting to catch up in the space race. The Russians passed the Americans again on March 18, 1965, when cosmonaut Alexei Leonov performed the first spacewalk during the one-day Voskhod 2 mission. However, with Gemini IV, NASA was quickly catching up. (https://www.nasa.gov/feature/gemini-iv-learning-to-walk-in-space). [NASA caption] CAPE KENNEDY, Fla. --The Gemini launch vehicle erector is lowered for the wet mock simulations May 14, 1965 at Launch Complex 19, for the Gemini IV four-day mission which is scheduled to be launched no earlier than June 3, 1965. The prime crew for the flight is James A. McDivitt, command pilot, and Edward H. White II, pilot. The backup crew for the flight is Frank Borman, command pilot and James A. Lovell Jr., pilot.