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Project Gemini – Springboard to the Moon

Spaceflight is an accepted part of today’s world. The International Space Station has been occupied continuously for the past 15 years, Astronaut Scott Kelly and Cosmonaut Gennady Padalka recently began a year-long stay in orbit, and there are commercial firms preparing to take fare-paying passengers into space. Orbital relays bring us nearly instantaneous communication with any part of the world and we can receive television in our homes that is broadcast directly from satellites. Global positioning system (GPS) satellites let us navigate with precision. Meteorologists track weather systems on a global scale using satellite imagery. Space has become so ubiquitous it is easy to sometimes overlook the pioneering efforts of half a century ago.
Project Gemini was one of the most significant pioneering programs of the mid-1960s, but it is often overshadowed by its successor, Project Apollo.
The early years of space exploration took place in the midst of the Cold War between the United States and Soviet Union. This led to a “Space Race” between the two global superpowers as each tried to demonstrate technological superiority in the new realm of exploration. Against this background of international competition, the Soviets stunned the world with the launch of Sputnik 1 on October 4, 1957. The Soviet Union had beaten America in the quest to launch the world’s first artificial satellite. Over the next few years, Soviet rocket scientists continued to rack up an impressive string of space “firsts” following Sputnik 1: first living creature in orbit (Sputnik 2); first spacecraft to impact the Moon (Lunik 2); first photographs of the lunar far side (Lunik 3); and first human in space (Vostok 1). These triumphs helped fuel a perception that the American space program lagged behind that of the Russians.
Vostok 1, launched on April 12, 1961, carried Cosmonaut Yuri Gagarin once around the world. The United States’ first piloted space mission, the Mercury Redstone flight of Freedom 7 crewed by Alan B. Shepard, Jr. on May 5, 1961, was a suborbital flight. Gagarin’s orbital flight lasted 108 minutes; Shepard’s suborbital one just 15 minutes. In an effort to overcome popular perceptions about the relative state of development between the Soviet and American space programs, President John F. Kennedy challenged his advisors to come up with a space goal. He stipulated that the goal had to be one that United States had a chance of achieving first and had to be on a sufficiently grand scale to capture the world’s imagination.
On May 25, 1961, President Kennedy announced that the United States would land a man on the Moon by the end of the decade. At the time, the total experience NASA had with humans in space was Shepard’s 15-minute suborbital flight. NASA already had a proposed 3-man spacecraft named Apollo on the drawing boards. With Kennedy’s pronouncement, Apollo became the lunar landing program.
Project Mercury’s goals were simply to demonstrate that a human could survive and work in space. To bridge the gap between Mercury and the very ambitious Apollo program, NASA needed an interim program that would develop all the techniques needed to reach the Moon. That program became known as Gemini. The Gemini spacecraft carried two astronauts. Project Gemini goals included:

  • Demonstrate orbital rendezvous and docking
  • Demonstrate extravehicular activity
  • Conduct missions lasting eight days or longer
  • Perfect techniques of atmospheric reentry and touchdown at a pre-selected point on the ground. (NASA dropped this objective in 1964.)

After two unmanned test flights, NASA launched the first piloted Gemini flight, Gemini-3, on March 23, 1965. Astronauts Virgil “Gus” Grissom and John Young piloted the spacecraft on a 3-orbit mission that lasted 4 ½ hours. They tested major spacecraft systems including the ability to modify their orbit. This technique was vital if future astronauts were going to rendezvous and dock with other spacecraft.
The next mission lifted off on June 3, 1965. James A. McDivitt and Edward H. White piloted Gemini 4 in space for four days, twice the length of any previous American manned space flight. Early in the flight, White performed the first extravehicular activity by an American astronaut.
Gemini set a very rapid pace for flights with a total of ten piloted missions between March 1965 and November 1966. Significant milestones during the Gemini flights included the first rendezvous in space (Gemini’s 6A and 7); an 8-day mission, which was the length of time required to fly to the Moon and back (Gemini 5); a two-week mission (Gemini 7); and the first docking in space (Gemini 8 and an unmanned Agena target vehicle). Gemini 11 astronauts Charles “Pete” Conrad and Richard Gordon performed a “direct ascent” rendezvous and docking, catching up with the Agena during their first orbit. The direct ascent profile simulated the maneuver that would be performed by the Apollo Lunar Module rendezvous with the Command and Service Module after landing on the Moon.
Half of the flights included EVAs (Geminis 4, 9A, 10, 11, and 12) and demonstrated that astronauts could perform useful work outside their spacecraft. Astronauts on Geminis 10 and 11 used the propulsion system on the Agena target vehicle to boost their orbits as high as 850 miles. Even though the precision landing on land goal had been dropped from the program, Gemini astronauts demonstrated techniques to control their splashdown points when they returned to Earth.
Sixteen individual astronauts flew on the ten piloted Gemini flights. (Four made two flights.) By the time Gemini 12 splashed down on November 15, 1966, American astronauts had demonstrated all the techniques needed to fly to the Moon and had amassed more than 1,993 man-hours in space. The stage was set for Project Apollo.