Image: Launch of first crewed Gemini flight
In a span of 20 months from March 1965 to November 1966, NASA developed, tested and flew transformative capabilities and cutting-edge technologies in the Gemini program that paved the way for not only Apollo, but the achievements of the space shuttle, building the International Space Station and setting the stage for human exploration of Mars.
The first crewed Gemini flight, Gemini III, lifted off Launch Pad 19 at 9:24 a.m. EST on March 23, 1965. The spacecraft "Molly Brown" carried astronauts Virgil I. "Gus" Grissom, command pilot, and John W. Young, pilot, on three orbits of Earth.
NASA's two-man Gemini spaceflights demonstrated that astronauts could change their capsule's orbit, remain in space for at least two weeks and work outside their spacecraft. They also pioneered rendezvous and docking with other spacecraft. All were essential skills to land on the moon and return safely to Earth.
Veteran Mercury astronaut Grissom was selected as command pilot of Gemini III, making him the first person traveling into space twice. Joining Grissom was Young, the first member of the second group of NASA pilots to fly in space. Young would go on to become the first person to make six spaceflights, including commanding Apollo 16 during which he walked on the moon. He also commanded STS-1, the first shuttle mission.
Gemini III's primary goal was to test the new, maneuverable spacecraft. In space, the crew members fired thrusters to change the shape of their orbit, shift their orbital plane slightly, and drop to a lower altitude. The revolutionary orbital maneuvering technology paved the way for rendezvous missions later in the Gemini Program and proved it was possible for a lunar module to lift off the moon and dock with the lunar orbiting command module for the trip home to Earth. It also meant spacecraft could be launched to rendezvous and dock with an orbiting space station.