Name: The Manhattan Project - 6 Minute English
Uploaded: 2022-05-21T16:45:34.000Z
Duration: 6 min 21 s
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Hello. This is 6 Minute English from BBC Learning English.

On August the sixth 1945, the US aircraft, Enola Gay,

dropped an atomic bomb on the city of Hiroshima,

When Japan refused to surrender, a second bomb

was dropped on Nagasaki three days later.

Many believe the bombings quickened the end of the Second World War.

which some have called a crime against humanity.

the US military and some of the world’s

leading scientific minds, was known as The Manhattan Project.

In this programme we’ll take a look into

the science and the politics of The Manhattan Project,

and as usual, we’ll learn some new vocabulary as well.

Even before World War Two, scientists had known

about the potential energy inside uranium, the

heaviest metal in the periodic table - a diagram which groups

the chemical elements into rows and columns according

The challenge for science was learning how to unleash

this potential energy in a controlled way.

We’ll hear more soon, but first I have a question

Well, oxygen is a gas, so it must pretty light.

OK, Rob, we’ll find out the answer later in

about the science of uranium from Frank Close,

an Oxford professor of theoretical physics,

in conversation with BBC Radio 4 programme,

In 1938 the discovery was made that if you use uranium,

the atoms of uranium, which are the heaviest that

occur naturally in the periodic table, they’re very fragile…

and the discovery was that if you just almost touched

them with a single neutron, that’s a nuclear particle,

it would just break apart, split in two… and this action

of splitting the uranium has become known as fission.

Atoms of uranium are very fragile – easily broken or damaged.

In 1938, it was discovered that when nuclear particles

called neutrons were fired at uranium atoms,

This process of splitting uranium, or fission, did two things.

First, it released huge amounts of energy,

a billion times more than would be released

Secondly, the act of splitting atoms released

These new neutrons were freed to hit more uranium,

creating four neutrons, which in turn were freed

and created eight, then sixteen and so on,

making what’s known as a chemical chain reaction.

The politics behind the development of the atomic bomb

In the same year that Hitler invaded Poland,

two Jewish scientists exiled from Nazi Germany,

Rudolf Peierls, and Otto Frish, first realised uranium’s

Listen as Professor Frank Close takes up the story for BBC Radio 4 programme In Our Time.

Now, what happened at that moment was, having had the idea and the shock of the discovery,

you immediately then think, ‘maybe scientists in Germany

have already had the same idea and come to the same

conclusions – could Hitler already be building such a weapon?

And in their memorandum which they wrote and reached the British

government they said it’s conceivable that Germany is

in fact developing this weapon, and the only defence

After their discovery, Peierls and Frish were worried

that the Nazis had already found out how to weaponise uranium.

It was conceivable, or believable, that Germany

They shared this terrifying thought in their famous memorandum

– a short written report on a specific topic.

As soon as US President Franklin Roosevelt read it,

he started the Manhattan Project, and the race to build

In a strange twist of history, it turned out that Hitler

hadn’t been building atomic bombs at all.

And Hiroshima, the Japanese city destroyed in 1945,

was rebuilt and stands as a symbol of peace today.

Let’s end on a lighter note, Sam, with your question.

Yes, I asked which is the lightest element

It’s A, hydrogen, the lightest of all gases which come at

the very start of the periodic table, having the atomic number 1.

Ah, if only I’d remembered what our chemistry teacher

taught us about the periodic table – a chart grouping all the chemical

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The Manhattan Project - 6 Minute English

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