Rockets into Space
ATLAS OF THE UNIVERSE
T
he idea of travelling to other worlds is far from
new. As long ago as the second century ADa Greek
satirist, Lucian of Samosata, wrote a story in which a
party of sailors passing through the Strait of Gibraltar
were caught up in a vast waterspout and hurled on to
the Moon. Even Johannes Kepler wrote ‘science fiction’;
his hero was taken to the Moon by obliging demons! In
1865 Jules Verne published his classic novel in which the
travellers were put inside a projectile and fired moonward
from the barrel of a powerful gun. This would be rather
uncomfortable for the intrepid crew members, quite apart
from the fact that it would be a one-way journey only
(though Verne cleverly avoided this difficulty in his book,
which is well worth reading even today).
The first truly scientific ideas about spaceflight were
due to a Russian, Konstantin Eduardovich Tsiolkovskii,
whose first paper appeared in 1902 – in an obscure
journal, so that it passed almost unnoticed. Tsiolkovskii
knew that ordinary flying machines cannot function in
airless space, but rockets can do so, because they depend
upon what Isaac Newton called the principle of reaction:
every action has an equal and opposite reaction. For
example, consider an ordinary firework rocket of the
type fired in England on Guy Fawkes’ night. It consists
of a hollow tube filled with gunpowder. When you ‘light
the blue touch paper and retire immediately’ the powder
starts to burn; hot gas is produced, and rushes out of the
exhaust, so ‘kicking’ the tube in the opposite direction. As
long as the gas streams out, the rocket will continue to fly.
This is all very well, but – as Tsiolkovskii realized –
solid fuels are weak and unreliable. Instead, he planned a
liquid-fuel rocket motor. Two liquids (for example, petrol
and liquid oxygen) are forced by pumps into a combus-
tion chamber; they react together, producing hot gas
which is sent out of the exhaust and makes the rocket fly.
Tsiolkovskii also suggested using a compound launcher
made up of two separate rockets joined together. Initially
the lower stage does all the work; when it has used up
its propellant it breaks away, leaving the upper stage to
continue the journey by using its own motors. In effect,
the upper stage has been given a running start.
Tsiolkovskii was not a practical experimenter, and the
first liquid-propellant rocket was not fired until 1926, by
the American engineer Robert Hutchings Goddard (who
at that time had never even heard about Tsiolkovskii’s
work). Goddard’s rocket was modest enough, moving for▲ Tsiolkovskii. Konstantin
Eduardovich Tsiolkovskii is
regarded as ‘the father of
space research’; it was his
work which laid down the
general principles of
astronautics.▲ Goddard. Robert
Hutchings Goddard, the
American rocket engineer,
built and flew the first
liquid-propellant rocket in- His work was entirely
independent of that of
Tsiolkovskii.
▼ The V2 weapon. The V2
was developed during
World War II by a German
team, headed by Wernher
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