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2.1. What was Mercury about?
Project Mercury was launched one year after Sputnik was shot into space on October 7, 1958 as NASA's first project. It had three prime objectives.
- to send manned spacecraft into orbit (circle Earth)
- to find out weather humans can work properly in space, and
- to recover both man and spacecraft safely.
The Mercury engineers were true pioneers. Nothing that they were doing has ever been done before. The engineers had to build a space capsule that protects humans in space from the vacuum, the freezing cold temperatures, the radiation of space that has just been discovered, and the astronauts had to survive the heat of the reentry into the atmosphere during which the spacecraft would be flying very fast.
The engineers found that the ideal shape for the spacecraft was bullet-like. They put strong heat shields on the front side so that the astronaut could survive the reentry. The Mercury capsules were driven into space by to different propulsion systems. At first the astronauts were boosted into space by Redstone Rockets which were only good for sub-orbital flights. Later the more powerful Atlas-D rockets were used. The Atlas-D was a modified ballistic missile. Its skin was extra thin to safe weight, so that it had to be pressurized from within.
Compared with today's standards the Mercury capsules were very small. They had about 12,000m3 of Volume which is just the right size for one person to squeeze in. The internal controls were powered with batteries. Inside there were 120 controls, and 90 switches and levers. Despite that great number of instruments Mercury was only able change its orientation in space.
2.2. Mission History
Out of a group of 110 military pilots, seven were chosen to become America's first Astronauts, the Mercury Seven. They all gave their spacecraft a name which ended with a 7 to emphasize the teamwork among them. Before they could go on their mission tests on animals, and even a breathing robot were conducted.
On May 5, 1961, a Redstone, that was given the name Freedom 7, was ready to take off. It took Allan B. Shepard Jr. on a 15 minute space ride that was watched by 45 million Americans on TV. He had the experience of weightlessness for five minutes while he was traveling in a height of 187km.
Nine months later it was John H. Glenn's turn to make the first trip with an Atlas-D, which he had named Friendship 7. Glenn remained in the orbit for almost five hours, circling Earth three times. After experiencing a sunrise and a sunset in space he returned safely to Earth as a national hero. The primary objective of the "Mercury Project" was thus fulfilled.
Other Mercury missions followed, most noticeably Faith 7 the last one which started in May 1963. It was supposed to be an endurance test. L. Gordon Cooper spent 34 hours in space and rounded Earth 22 times. On board he slept, and made some great pictures of the Earth. He was also the first person to launch a satellite in space.
2.3. The Importance of Mercury
The Mercury Project answered many of the basic questions about space flight. It has proven that is possible to build rockets that are strong enough to launch humans into space, and that they could survive there. The engineers gained much experience and learned about the difficulties of preparing a rocket. It also showed that a global communications network was necessary to make the missions more secure.
The program was so successful that the last scheduled mission could be canceled. President Kennedy announced in 1961 that the United States would reach the Moon before the end of the decade. By 1963 most of the Mercury engineers had already been working on NASA's other projects: Gemini and Apollo.
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