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The Chinese were very early
on the rocket scene. They had a simple form of gunpowder which
was put into bamboo shoots then thrown into fires. The resulting
somewhat haphazard explosions were used mainly during religious
and festive celebrations. These short firecracker tubes were
later attached to arrows and long sticks, looking very much
like our rocket fireworks today, and so the early rocket was
born.
Sometime in 1232 AD was when
the first use of true rockets occurred. The Chinese and Mongols
were at it, and during the nasty battle of Kai-Keng the Chinese
repelled the Mongol invaders with a barrage of "arrows of
flying fire." Indeed all use of rockets from this time on
were for wars or firework displays - there's a contrast!
Sir Isaac Newton gave the
scientific reasons the explain why rockets work in the late
17th century. His third law of motion explains that every
action has an opposite and equal reaction. For a rocket, the
action is the thrust downward at lift-off and the reaction
is the movement of the rocket upward.
In 1883 a Russian school master
Konstantin Eduardovich Tsiolkovsky began explaining the idea
of how a rocket could fly in space and also made the first
mention of artificial satellites. Later, his major achievement
was to suggest certain liquids could be used as fuel for rockets.
The benefits are that liquid fuel could be more easily controlled
while also giving a greater thrust than solid fuel. His suggested
fuel combination, written in 1903, was eventually used to
send the Apollo astronauts to the Moon - how remarkably advanced
Konstantin was. His ideas even included use of a multi-stage
rockets to achieve the highest speeds possible, exactly as
the Apollo Saturn V rockets did as well. Looking further ahead
his thoughts even stretched to the development of Space Stations.
Konstantin never flew a rocket,
but we know a man who did: Robert Goddard. In 1912 he fired
a solid fuel rocket so very high in the sky which proved that
rockets did not need the air in our atmosphere to 'push' against.
Therefore, they would work ever so happily in the near-vacuum
of space. Newton had already said this of course, but no one
was listening.
After solid fuel experiments
Goddard, like Tsiolkovsky, looked at liquid fuel and all its
possibilities. No one had built, let alone flown a liquid
fuel rocket before. It was a much harder task to build than
a solid fuel rocket - you need fuel tanks, turbines and combustion
chambers. Goddard overcame all the difficulties and on 16th
March 1926 he achieved the first successful flight of a liquid
fuel rocket. His rocket, launched from Auburn, Massachusetts
USA, flew for two and a half seconds, climbed 12.5 metres,
and landed 56 metres away in a cabbage patch! It's average
speed during this short, but monumental, flight was 64 mph
or 103 km/h. Rober Goddard made many more rockets, each one
improving and growing larger with each successive design.
While Robert tinkered away
in the United States, rocketry things were happening in Europe.
A German physicist and mathematician Hermann Oberth, actually
born in Transylvannia, published a small book called "The
Rocket into Interplanetary Space" which detailed the principles
of rocketry flight. His little book inspired several groups
of rocket societies around the world including, in Germany,
the Society for Space Travel, which eventually led to the
building of the frightening V-2.
After World War II many German
rocket scientists, together with plenty of unused rocket bits,
went to the Soviet Union or the United States. Both countries
developed many medium and long range intercontinental ballistic
missiles from their expertise. It was these missiles that
became the early rockets for the space programs of the late
1950's.
The Russian's led the way
into space on 4th October 1957 when Sputnik 1 became the world's
first Earth-orbiting artificial satellite. This tiny man-made
moon was a 58 cm (23 inches) diameter sphere of aluminium
weighing 83.5 kg (184 lb). The first American satellite was
Explorer 1, launched on 31st January 1958. Measuring just
15 cm (6 inches) in diameter, and weighing only 14 kg (31
lb), Explorer 1 was much smaller than its Soviet counterpart.
Rockets developed dramatically
over the next ten years as the Space Race entered full swing.
In America the relatively small 83 ft-long (25 m) Mercury
Redstone eventually made way for the largest rocket ever made:
the 364 ft (111 m) American Saturn V launcher (both rockets
pictured in the right column). The majority of this enormous
craft was used as fuel tanks, and it used a LOT of fuel. The
main five engines had a combined thrust of 40 jumbo jets,
which used 3 tonnes of fuel every second. The temperature
of all this lot reached a balmy 3000 degrees Celsius!
Certain spacecraft are not
happy with using just one type of fuel, such as the well-known
Space Shuttle, which uses a combination of liquid AND solid
fuel rockets.
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