Page 111 - BBC History The Story of Science & Technology - 2017 UK

Frank Whittle
(right)
explains the
workings of
his jet engine

Who really Unless it’s really old, every
discovered… glass of wine is radioactive
Neptune? What connects ...

nuclear weapons
On the night of 23 September
1846, German astronomer
Johann Galle noticed an with fine wine?
object in the constellation
Aquarius that didn’t appear In 1945, the US Army conducted the first
on the latest star maps. nuclear weapons test as part of the Who really
Its disc-like appearance Manhattan Project. Since then, there invented…
suggested that it was have been more than 2,000 nuclear
a planet – a conclusion explosions around the world.
confirmed the following night the jet engine?
by its movement relative to Each nuclear explosion releases several
the distant stars. hundred grams of the radioactive The basic idea of creating motion by
Galle’s discovery of the isotope caesium-137. This has a half-life directing a jet of fluid in the opposite
planet now called Neptune of about 30 years, and is not normally direction to the desired direction of travel
was no coincidence. He had found in nature. dates back to ancient times. In the first
been asked to examine that century AD, the Greek mathematician
patch of the night sky by Caesium-137 dust from nuclear explo- Hero of Alexandria described a device
Urbain Le Verrier, a brilliant sions gets dispersed in the atmosphere propelled by steam squirted out of two
French theoretician who had and reacts with rainwater to form soluble opposing nozzles. However, it’s unlikely
been studying strange effects salts that are absorbed in tiny quantities that it would have worked – the jets were
in the orbit of Uranus, and by plants through their roots. probably too weak to overcome friction
concluded that it was being between its various components.
affected by an unseen planet. Any wine bottled after 1945 contains In 1922, French engineer Maxime
But while Galle and Le Ver- detectable amounts of caesium-137 Guillaume was granted a patent for a
rier were being hailed for their (though it is quite safe to drink). This fact simple jet engine. Though it was never
discovery, British astrono- has been used to test claims of extreme built, the idea was right. It consisted of
mers claimed that a young age in bottles of wine. a series of turbines that compressed air,
Cambridge mathematician, which was then mixed with fuel and
John Couch Adams (pictured ignited. The resulting rapidly expanding
above), had made similar gas produced thrust.
calculations, and that a British The first to succeed in making this
astronomer had subsequently approach work was a young RAF
seen Neptune three times – engineer named Frank Whittle. In the
but failed to recognise it. This 1920s he devised an arrangement of
attempt to grab some of the turbines and compressors that, he
glory sparked an international claimed, would produce enough thrust
row that intensified when for aircraft propulsion. The UK air
American scientists argued ministry disagreed, however, so Whittle
that the predictions of both Any wine bottled set up his own company, which pro-
were faulty and the discovery duced the first working jet engine in
merely a happy accident. since 1945 contains 1937. By then, German physicist Hans
Recent research has led von Ohain had hit on a similar solution,
historians to dismiss the the radioactive and was ahead of Whittle in achieving
British claim. In any case, it’s the first actual flight of a jet aircraft – the
now known that Galle wasn’t isotope caesium-137 – Heinkel He 178 – in August 1939.
the first to see Neptune: though thankfully it
GETTY/ALAMY studies of Galileo’s note- is quite safe to drink
books show that he spotted
it as early as 1612.

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