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The new NASA organization, formed to take over the exploration of space, now needed to put a man in space before the Soviets. The Soviets had already beaten them to launching the first satellite, and they ultimately put a man in space before Alan Shepard went up in Mercury 1. They needed a small spacecraft able to suppory a single person in the vaccum of space. In order to design it, in 1959, NASA requested to several companies that they submit proposals for the first American space capsule.
McDonnell Aircraft Corp. won the contract with a bell
shaped capsule just under three meters tall, and two meters in
diameter. This capsule had a square hatch in the side, which was
barely large enough for the astronaut to squeeze through. Once
inside, the astronaut sat in a couch which was specifically
designed for him. In front of him was a control panel and two
small portholes. (following complaints from the astronaut, later
versions of the Mercury capsule and a large rectangular window)
also, the assets could view the outside with a retractable
telescope. To control the attitude and velocity (attitude is the
direction the capsule is facing) 18 small thrusters could be
controlled by the Astronaut's hand, and were also controlled by
other control systems for extra safety. Inside the capsule was
pure oxygen and one third the pressure at sea level. In case the
cabin lost pressure, a spacesuit that the Astronaut war could act
as a backup life support system by providing an independent
oxygen supply
The capsule itself was made out of a titanium and nickel alloy, and the heat shield on the bottom was made from a fiberglass reinforced laminated plastic. This heat shield was designed to emulate, or charge, to absorb the heat during reentry the. The Mercury capsule was designed to be launched using either a Redstone or Atlas rocket, althogh an orbital flight could only be performed using the more powerful Atlas rocket.
There were seven Astronaut chosen to pilots the Mercury capsules. Six of the 7, all except for Donald K. Slayton and, flew missions in the Mercury capsule. Slayton was grounded because of a heart irregularity. However, he stayed with NASA and eventually convinced NASA officials that his heart irregularity was not a danger. He eventually got to fly on the famous Apollo-Soyuz international docking mission in 1975.
On the fifth of May 1961, Mercury 1 was launched. The Redstone rocket which carried it into a sub-orbital flight gave it 15 minutes and 22 seconds in space. The first Astronaut in space, Alan B. Shepard, reached a peak altitude of 185 kilometers in his capsule, Freedom 7. Although Shepard was the first American in space, he was not be first person in space. He was beaten by the Soviet Yuri Gagarin.
Mercury 2, or Liberty Bell 7, flew on the twenty-first of July 1962. Virgil Grissom piloted this sub orbital flight. This was the first manned mission in space to involve unexpected danger, because after the capsule landed, the explosive bolts blew the hatch open for no apparent reason. Water rushed immediately into the capsule, which quickly sank. Although Grissom escaped, his space suit was weighed down with water and he was unable to swim. A helicopter was able to eventually rescue Grissom, the capsule could not be recovered.
On the thirteenth of September 1961, an unmanned capsule made the first orbital flight of the Mercury spacecraft. This successful test lead to Mercury 3, which Colonel John Glenn flew. On this 5 hour flight, he flew an orbit 160 kilometers by 261 kilometers across. Whenever his craft emerged from the dark side of the Earth, Glenn observed a strange aura of thousands of tiny luminous particles surrounding his ship. These were later found to be particles released from the capsule, reflecting light from the sun. Like Mercury 2, Mercury 3 (also known as friendship 7) had a dramatic ending. It started when ground controllers suspected that the heat shield of the craft was loose. If it broke off during reentry, the Mercury capsule would be destroyed. To prevent this, a retrorocket pack that was attached to the heat shield was made to stay in place. By this, they hoped that the straps holding the retrorocket pack would also hold the heat shield on. After a dramatic landing, with flaming debris flying test plans window during reentry, the capsule was undamaged.
After Glenn's flight of Mercury 3, there were three more missions of the Mercury spacecraft. The first was Mercury 4, or Aurora 7, flown by Malcolm Scott Carpenter on the twenty-fourth of May 1962. Because of extensive maneuvers in orbit, Mercury 4 became dangerously low on fuel and landed 350 kilometers off target. Mercury 5 was flown on the third of October 1962 by Walter M. Schirra aboard sigma 7. The final Mercury flight was flown by L Gordon Cooper on the fifteenth of May 1963.
Although one more mission was planned, NASA decided to terminate it in favor of the Gemini project. In the beginning of the 60's, Mankind had not yet put anybody in space. In less than a decade, in 1969, man would be on the moon with Apollo. In that decade, we went from a planet trapped on Earth by gravity, to a planet with the capability of interplanetary travel.
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