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Atlas-Mercury |
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The Atlas family of launch vehicles was named after the
mighty god of Greek mythology, who supported the world on its shoulders. Unlike
other US missiles, it was not developed by Wernher von Braun and the German
scientists. Rather it was independently developed by the US Air Force as America's
first ICBM (intercontinental ballistic missile). It's cold war mission was to
deter a nuclear attack.
It's first successful flight was in December of 1957. By 1965,
over 1,000 Atlas missiles were deployed in underground silos throughout the northern part
of the United States. Each carried a nuclear warhead aimed at a military target in
the Soviet Union.
The original Atlas was 90 feet long and 12 feet in diameter.
It used liquid-propellant. Its first design was called a "stage and a
half" because it had a single main engine with side by side booster engines, all
powered by liquid oxygen and kerosene. All three engines fired at launch, but the two
boosters dropped away during the first stage burn. This Atlas had a takeoff thrust
of 350,000 pounds.
Not long after it became operational, the well-proven design was
brought into NASA service. It's most significant mission was part of Project
Mercury. The mission goal was to put a human into orbit, study his or her
physical and mental reaction to the environment, and return them safely. This
was accomplished on Feb. 20, 1962, when the Atlas-launched Friendship 7 carried John Glenn
into space, making him the first American astronaut to orbit the Earth. The
Atlas Mercury was unique in that a special safety tower and rocket was mounted on top of
the capsule to permit it break away from the main missile if a problem developed during
launch.
Although the Atlas played an important role in the
manned-launch program, that role was taken over by the Titan II in 1965. New, more
powerful versions of the Atlas were soon developed, including the E and F models. Soon,
powerful second stages were added. First the Agena and later
the Centaur. All were used to launch satellites. |
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Atlas-E |
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| The end of the cold war resulted in the US dismantling its nuclear deterrent
force. The old Atlas worriers had never seen combat (Thank God!) and were retired
from military service. Today, equipped with Centaur IIAS second stages, they provide
an inexpensive way to place communications and other satellites in orbit. The Atlas
IIAs, can place 8,150 pounds in geosynchronous orbit and 19,050 pounds into low Earth
orbit. |
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