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3.1. Just another step on the way to the Moon?
After the success of Mercury the Gemini Program was showing the Gemini Program was introduced to the public on January 3, 1962. At this time Apollo had already been called into life. To the public it was not as interesting as Mercury or Apollo since it was not real pioneering anymore. It was a mere preparation for the Apollo program. The Gemini Program had three main objectives.
The first was to accomplish space fights of two weeks in duration. The lunar missions would later take the same time. So NASA had to demonstrate the man and machine could work in space for so long.
The second goal was to dock with orbiting vehicles and to maneuver the docked combination using the propulsion system. Later these techniques would be used when the lunar lander separates from the command module in the lunar orbit.
The third was to perfect the methods of reentry into the atmosphere and land on a pre-selected point on Earth. The goal of making a landlanding was canceled in 1964, however.
The Gemini capsule was an improvement of Mercury. That's why it was originally called "Mercury Mark II". It had to be maneuvered by two pilots. The module had twice the weight of the Mercury capsules, but size of the cabin was increased by only 50 per cent. As a result the Gemini capsules appeared to be more cramped. In case of emergency the pilots could leave the capsule with an escape rocket instead of ejection seats. The batteries that provided Mercury with electrical power were replaced with fuel cells.
The capsule sat on a Titan 2 launch vehicle. The docking maneuvers were practiced with unmanned Agena upper stages that were always started shortly before the Titan 2 rockets. In order to fly the complicated docking maneuvers the maneuvering capabilities of Mercury have been improved a lot. Gemini was able to fly forward, backward, and sideways on its way around Earth. It was even possible to change orbits. These maneuvers required great precision, so besides the two astronauts the first board computers were required to make complex calculations.
The constructors of Gemini had to avoid long delays between the flights. Many parts of the spaceship were reusable. Thus the coast of the project have also been lowered. In only 20 months ten Gemini missions were launched. As there was little time between the flights space flight became routine. The ground operations became smoother and the risk for the astronauts decreased after every mission.
3.2. Important Missions
The first manned Gemini mission (Gemini 3) took off on March 23, 1965. It was a successful test of the design and lasted just four hours. The first full-time Gemini mission was launched on June 3, 1965, and returned safely four days later. Its highlight was the first space-walk ever. James McDivitt left the capsule for 22 minutes tied to a tether.
The goal of a two week space flight was accomplished by Gemini VII from December 4-18, 1965. The mission solved many problems of long-duration space flight. It included studies of nutrition in space and proved that even longer trips to space do not pose a threat to the astronaut's health. The Gemini VII pilots also managed to rendezvous with an Agena for the first time.
The most exciting Gemini mission was undoubtedly Gemini VIII that took off on March 16, 1966. Its objective was to achieve the first docking maneuver ever. The pilot Neil Armstrong approached the Agena carefully and managed to dock. The successful action was almost followed by a catastrophe. While docked to the Agena the Gemini capsule began rolling over. A thruster was stuck and could not be deactivated. The crew undocked immediately and the capsule began rotating even faster, at the rate of one revolution per second. In order to stop the motion the astronauts had to use their reentry thrusters. They used up much of their fuel so that an emergency landing had to be made as soon as possible. 10 hours after launch Gemini VIII was already back on Earth.
The last Gemini mission was launched on November 11, 1966. By then all the goals of the Gemini project had been accomplished. Space-walks and complicated maneuvers such as rendezvous and docking procedures had become routine. Fears about the risks to health had been eliminated. The final objective of Gemini (smoothing the reentry) has been completed when the board computer controlled the reentry. Now it was time to tackle the next mission: the flight to the Moon.
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