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During
the latter part of the 17th century, the scientific foundations for modern
space travel was laid out by the great English scientist Sir
Isaac Newton (1642-1727). Newton organized his understanding of physical
motion into three scientific laws. The laws explain how rockets work and
why they are able to work in the vacuum of outer space. Newton's laws soon
began to have a practical impact on the design of rockets. About 1720,
a Dutch professor, Willem Gravesande, built model cars propelled by jets
of steam. Experimenters and scientists in Germany and Russia began working
with rockets with a mass of more than 45 kilograms. Some of these were
so powerful that their escaping exhaust flames bored deep holes in the
ground even before lift-off.
During the end of the 18th century
and early into the 19th, rockets experienced a brief revival as a weapon
of war. The success of Indian rocket barrages against the British in 1792
and again in 1799 caught the interest of an artillery expert, Colonel William
Congreve. Congreve set out to design rockets for use by the British military.
The Congreve rockets were highly
successful in battle. Used by British ships to pound Fort McHenry in the
War of 1812, they inspired Francis Scott Key to write "the rockets' red
glare," words in his poem that later became The Star- Spangled Banner.
Even with Congreve's work, scientists
had not improved the accuracy of rockets much from the early days. The
devastating nature of war rockets was not their accuracy or power, but
their numbers. During a typical siege, thousands of them might be fired
at the enemy. All over the world, researchers experimented with ways to
improve accuracy. An English scientist, William Hale, developed a technique
called spin stabilization. In this method, the escaping exhaust gases struck
small vanes at the bottom of the rocket, causing it to spin much as a bullet
does in flight. Variations of the principle are still used today.
Rockets continued to be used with
success in battles all over the European continent. However, in a war with
Prussia, the Austrian rocket brigades met their match against newly designed
artillery pieces. Breech-loading cannon with rifled barrels and exploding
warheads were far more effective weapons of war than the best rockets.
Once again, rockets were relegated to peacetime uses.
Modern Rocketry
Begins
In 1898, a Russian schoolteacher and
scientist, Konstantin Tsiolkovsky
(1857-1935), proposed the idea of space exploration. In a report he published
in 1903, Tsiolkovsky suggested the use of liquid
propellants for rockets in order to achieve greater range. Tsiolkovsky
stated that the speed and range of a rocket were limited only by the exhaust
velocity of escaping gases. For his ideas, careful research, and great
vision, Tsiolkovsky has been called the father of modern astronautics.
 Early
in the 20th century, an American scientist, Robert
H. Goddard (1882-1945), conducted practical experiments in rocketry.
He had become interested in a way of achieving higher altitudes than were
possible for lighter-than-air balloons. He published a pamphlet in 1919
entitled A Method of Reaching Extreme Altitudes. It was a mathematical
analysis of what is today called the meteorological sounding rocket.
Goddard's earliest experiments were
with solid-propellant
rockets. In 1915, he began to try various types of solid fuels and
to measure the exhaust velocities of the burning gases. While working on
solid-propellant rockets, Goddard became convinced that a rocket could
be propelled better by liquid fuel. No one had ever built a successful
liquid-propellant rocket before. It was a much more difficult task than
building solid- propellant rockets. Fuel and oxygen tanks, turbines, and
combustion chambers would be needed. In spite of the difficulties, Goddard
achieved the first successful flight with a liquid-propellant rocket on
March 16, 1926. Fueled by liquid oxygen and gasoline, it flew for only
two and a half seconds, climbed 12.5 meters, and landed 56 meters away
in a cabbage patch. By today's standards, the flight was unimpressive,
but like the first powered airplane flight by the Wright brothers in 1903,
Goddard's gasoline rocket was the forerunner of a whole new era in rocket
flight.
Goddard's experiments in liquid-propellant
rockets continued for many years. His rockets became bigger and flew higher.
He developed a gyroscope system for flight control and a payload compartment
for scientific instruments. Parachute recovery systems were employed to
return rockets and instruments safely. Goddard, for his achievements, has
been called the father of modern rocketry.
A third great space pioneer, Hermann
Oberth (1894-1989) of Germany, published a book in 1923 about travel
into outer space. His writings were important. Because of them, many small
rocket societies sprang up around the world. In Germany, the formation
of one such society, the Verein fur Raumschiffahrt (Society for Space Travel),
led to the development of the V-2 rocket, which was used against London
during World War II. In 1937, German engineers and scientists, including
Oberth, assembled in Peenemunde on the shores of the Baltic Sea. There
the most advanced rocket of its time would be built and flown under the
directorship of Wernher von Braun.
 The
V-2
rocket (in Germany called the A-4) was small by comparison to today's
designs. It achieved its great thrust by burning a mixture of liquid oxygen
and alcohol at a rate of about one ton every seven seconds. Once launched,
the V-2 was a formidable weapon that could devastate whole city blocks.
Fortunately for London and the Allied
forces, the V-2 came too late in the war to change its outcome. Nevertheless,
by war's end, Germany's rocket scientists and engineers had already laid
plans for advanced missiles capable of spanning the Atlantic Ocean and
landing in the United States. These missiles would have had winged upper
stages but very small payload capacities.
With the fall of Germany, many unused
V-2s and components were captured by the Allies. Many German rocket scientists
came to the United States. Others went to the Soviet Union. All the scientists
from Germany, including Wernher von Braun, were amazed at the progress
Goddard had made.
Both the United States and the Soviet
Union realized the potential of rocketry as a military weapon and began
a variety of experimental programs. At first, the United States began a
program with high-altitude atmospheric sounding rockets, one of Goddard's
early ideas. Later, a variety of medium- and long-range intercontinental
ballistic missiles were developed. These became the starting point of the
U.S. space program. Missiles such as the Redstone, Atlas, and Titan would
eventually launch astronauts into space.
On October 4, 1957, the world was
stunned by the news of an Earth-orbiting artificial satellite launched
by the Soviet Union. Called Sputnik
I, the satellite was the first successful entry in a race for space
between the two superpower nations. Less than a month later, the Soviets
followed with the launch of a satellite carrying a dog named Laika on board.
Laika survived in space for seven days before being put to sleep before
the oxygen supply ran out. A few months after the first Sputnik, the United
States followed the Soviet Union with a satellite of its own. Explorer
I was launched by the U.S. Army on January 31, 1958. In October of
that year, the United States formally organized its space program by creating
the National Aeronautics and Space Administration (NASA).
NASA became a civilian agency with the goal of peaceful exploration of
space for the benefit of all humankind.
Soon, many people and machines were
being launched into space. Astronauts orbited Earth and landed on the Moon.
Robot spacecraft traveled to the planets. Space was suddenly opened up
to exploration and commercial exploitation. Satellites enabled scientists
to investigate our world, forecast the weather, and to communicate instantaneously
around the globe. As the demand for more and larger payloads increased,
a wide array of powerful and versatile rockets had to be built.
Since the earliest days of discovery
and experimentation, rockets have evolved from simple gunpowder devices
into giant vehicles capable of traveling into outer space. Rockets have
opened the universe to direct exploration by humankind.
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