Alchemy, the dream of turning base metals into gold,
used to be an offence punishable with a long prison sentence.
But here at one of the most advanced
nuclear research facilities in the world
they're attempting a new type of alchemy.
They're trying to command the extreme forces of nature
and make one element change into another brand new element.
This is the latest chapter in the extraordinary story of
scientists' battle to control the building blocks
that make up our universe.
The elements.
I'm Jim Al-Khalili.
As a nuclear physicist my life's work wouldn't have been possible
without the pioneering chemists
who first explored the mysteries of matter.
It's beautiful.
I've seen how they laboured to discover hidden elements and
crack the secret code of the natural world to create the periodic table.
Now the story turns to the scientists who unlocked
the potential of the 92 elements which made up our planet.
I'll discover how they endeavoured to combine them
and create our modern world.
Their mission to control nature is a tale of struggle and serendipity,
of accident meeting design.
And of the power of the elements harnessed
to release unimaginable forces.
Everything around me has been created as the result
of chemical reactions unlocking the power of the elements
and turning them into compounds.
The element iron fortified with chromium, carbon and nickel
makes the stainless steel cladding around this building.
Its glass is a union of silicon and oxygen.
Just 92 elements created our planet.
Our quest to combine them spans centuries.
People had been mixing, muddling
and making compounds from prehistoric times.
Inspired by the alchemists, early experimenters added
all sorts of chemicals together just to see what happened.
But it was more cooking than a real science,
what you might call "bucket chemistry".
Unsurprisingly some of the earliest breakthroughs
were made entirely by chance.
One discovery by a German chemist,
Heinrich Diesbach, was a milestone in the paint industry.
Science historian Professor Allan Chapman
is going to show me how Diesbach stumbled across the ingredients
of the first synthetic paint.
Hello, Allan. Good to see you.
Wonderful engine isn't she? Fantastic.
The development of the paint that goes onto these engines
which we call Brunswick Green was itself a mixture
of two artificially developed paint compounds in the 18th
and early 19th century.
The first of these was Prussian Blue,
developed in the 18th century, a deep beautiful, rich blue.
And mix that with another chemical substance, chrome yellow,
then you produce these wonderful colours
which Isambard Kingdom Brunel and his successors painted on these gorgeous
Great Western railway engines.
Before the discovery of Prussian Blue, most pigments
were derived from nature.
The best blue pigments came from rare lapus lazuli.
Allan Chapman is going to try to recreate Diesbach's discovery.
He's starting with one unusual ingredient
that ended up in the recipe by accident.
First of all, take your blood.
Take your blood.
And pour it into the crucible.
And then we take the potash, and the potash is the alkaline material
which we now call potassium carbonate.
Diesbach was trying to make red paint, not blue,
but he had no idea his potash had been contaminated.
And we think of course that it was the blood that formed the contaminant
that changed the reaction of the colour
and produced a blue rather than a red.
Heating blood alters its proteins, enabling them to combine with
the iron in blood cells and the potassium carbonate, or potash.
What's happening in the reaction now is that the carbonate is reacting
with the haemoglobin
and other structures in the blood to produce this extraordinary, thick,
what might best be simply called a gunge.
After heating the gunge to an ash and then filtering and diluting it,
Diesbach added green vitriol,
what we now call iron sulphate, unaware he was about to create
a complex iron compound, Ferric ferrocyanide, or Prussian Blue.
Now, watch this carefully,
it will effervesce and might effervesce violently. So watch this.
Look at that!
And notice the very nice green beginning to emerge.
Now for the final solution, it says to add the spirit of salt.
This acid should help draw out the Prussian Blue.
And shut the cupboard down
because it will throw off all sorts of toxic gases.
There we are. Now, you're talking. There's a real deep one!
Almost caught the bottle. Look at that.
Now that is Prussian blue, that's brilliant.
That's lovely, isn't it? The very first ever synthetic pigment,
and dry that out and pulverise it
and mix it up as a powder and you have a paint.
Diesbach's chance encounter with blood had given the world synthetic
Prussian Blue paint from a compound of iron.
Iron is the Earth's most abundant element.
Our planet is essentially a vast sphere with an iron core.
Though it's a silvery, lustrous metal,
contact with damp air sees it quickly rust.
The planet Mars is thought to be red due to iron oxide.
Adding just 1.7% of carbon makes iron into the more durable steel,
which helped launch the Industrial Revolution.
Diesbach had glimpsed the potential of making compounds.
But scientists' understanding of how elements combined
and could be controlled was still hazy.
In a bid to master the elements, one German chemist, Justus von Liebig,
became obsessed with creating explosive combinations.
His passion was sparked when, as a child in Darmstadt,
he saw a peddler letting off fireworks.
They were powered by silver fulminate,
the same chemicals found in bangers.
Liebig had found his vocation.
But it was as much Liebig's personality
as his love for explosives which powered his great breakthrough.
It was said that he was arrogant, irascible, pugnacious and pigheaded.
Not a man to cross you might think.
So when German chemist Friedrich Wohler got an
angry letter from Liebig in 1825, you can imagine his heart sinking.
Liebig had read a paper written by Wohler
about a compound he had made called silver cyanate. This is its formula.
It's made in equal parts from the elements
silver, carbon, nitrogen and oxygen.
Wohler described it as harmless and stable.
Liebig saw silver, carbon, nitrogen and oxygen and exploded
because this was exactly what made up HIS silver fulminate.
How could two substances that were apparently made of
the same amounts of the same elements, behave so differently?
True to character, Liebig decided
there was only one answer, that Wohler was wrong.
He dashed off a furious letter to Wohler
slamming him as a hopeless analyst.
Well, Wohler wasn't having any of that.
He challenged Liebig to make Silver cyanate and test it for himself.
Dr Andrea Sella has studied 19th century chemistry
and is attempting to create Wohler's silver cyanate.
The rules of chemistry really said that the only thing that counted was
what in your material, what its composition was.
And, so here we have this lovely white powder
which we're now going to filter off
and according to the then rules of chemistry,
this should be absolutely identical to Liebig's material.
And what would Liebig have expected to happen?
Liebig expected something really quite nasty.
I actually made a small amount of it earlier
and we'll put it here on this little piece of aluminium foil.
You take a match...
If this was Liebig's material then something interesting should happen.
Why don't you have a go? I'll step back.
Thank you very much(!)
Are you sure about this? Should I...
Go for it.
Be a chemist.
HE LAUGHS
Nothing. Nothing.
Now this would have been totally shocking to Liebig
because Liebig was expecting that something which
had silver, carbon, nitrogen and oxygen in it would be explosive.
And yet here was something with the same composition
and yet it didn't go bang.
So, same ingredients, same elements in the same proportions. Absolutely.
But they had to be two different compounds.
They were two totally different compounds.
Liebig and Wohler had discovered a fundamental characteristic
of the elements.
One which would in time explain how just 92 elements
could give rise to the extraordinary complexity of the modern world.
They'd stumbled on what would later be called "isomers".
What made their compounds different
was the way that the elements were connected.
If I take these building blocks I can use them to make...
a space shuttle...
..or a plane...
..or a boat.
It all depends how I fit the pieces together.
The same is true with the elements.
Like the explosive fulminate or the calm cyanate.
It seems that the same elements combined together in different ways
will give rise to different compounds with different properties.
Chemists began to suspect that the key to designing new compounds
was in understanding how the elements combined.
And this was all down to atoms.
Atoms are infinitesimally small particles of matter.
The image of these silicon atoms
is magnified more than 10 million times.
These are gold atoms. At the start of the 19th century,
science first began to consider
that all elements may be composed of atoms.
What scientists now realised was that the arrangement of
the atoms, the way they were connected together, was crucial.
And by studying the element carbon
hey made one of chemistry's great breakthroughs.
In 1796 Yorkshire chemist, Smithson Tennant, was investigating what
diamonds were made of, when he decided to burn one.
Now he used sunlight and a magnifying lens to heat the diamond.
But I'm going to speed things up and use a glass blowing torch
and I have some liquid oxygen.
Now if I hold this then in the flame and heat it up...
And there we have it whizzing around, that's beautiful.
The bubbles coming off were collected by Smithson Tennant,
they're pure carbon dioxide.
Now, he knew that he'd started with just two ingredients -
diamond and oxygen.
And what he produced was a gas made up of just carbon and oxygen.
So, he knew that diamond had to be carbon.
Now that's almost disappeared.
It's gone. That diamond doesn't exist any more,
it's in the air that I'm breathing. It's turned into carbon dioxide.
So, unfortunately diamonds aren't forever.
Tennant's revelation left scientists with a conundrum.
They knew carbon already,
as graphite, one of the softest elements on the planet.
So how could it be the same element as the hardest substance, diamond?
What was carbon's secret?
At the end of the 18th century, Tennant didn't yet know that
elements were made of atoms, so he was unable to find the answer.
It would be another half century before a young Scotsman
called Archibald Scott Couper took up the challenge.
Couper was a rising star in chemistry.
In 1856 when he was 27, he went to Paris to work with one of
the eminent chemists of the day, Charles-Adolphe Wurtz.
Couper was fascinated by the way
carbon atoms combined with other atoms.
And he came up with the idea of bonds, links between the atoms
to explain how the elements join with each other.
This is Couper's paper, written in June 1858.
The ideas in here would spark a revolution
in the way we interpret chemistry.
And this is Couper's picture of the way the atoms are connected.
The C stands for Carbon and the H for hydrogen,
and these lines are Couper's bonds
that explain how he thought
the atoms all joined together.
And this is the real genius,
somehow Couper realised that carbon doesn't just have one link,
but four.
Because of its four bonds, it can attach with different strengths
to other carbon atoms, that's why it can exist in two extreme forms.
In diamond, all four bonds are connected to other carbon atoms in
three dimensions, that's why diamond is so hard.
But in graphite, only three of the bonds are connected to other carbon
atoms in a single plane, making the connections weaker,
which is why graphite is a much softer material.
Carbon's four bonds give it another extraordinary property.
Imagine I am a carbon atom.
I can use one hand to link to another atom and my other hand
to link to a second, leaving my feet free to make more links.
So, carbon's four bonds means it can combine
with lots of other atoms.
It can form rings and long chains,
something that makes it rare amongst the elements.
Carbon. It has us in its nurturing grasp from our birth to our death.
It's found in everything from a whale's backbone
to the smallest virus.
Carbon is in DNA, cellulose, fat, sugar.
Daily, each of us takes in 300g of it.
Earth's carbon, like most other elements,
was ejected from dying stars which means
we're all made of stardust.
Couper had solved a fundamental puzzle.
He'd explained why carbon could be found in so many compounds,
why it made up so much of the natural world.
Now, he just had to publish his findings to claim the credit.
But a German chemist,
Friedrich Kekule had hit upon exactly the same idea.
Kekule spent time studying in London, and it was apparently whilst
on a London bus that he claimed he'd had a flash of inspiration.
Most of us sit on the bus dreaming about Leeds United, what we're going
to have for supper when we get home, or what's on the telly.
But Kekule claimed he dreamt of
whirling atoms embracing in a giddy dance.
He saw them uniting into chains,
pulling more atoms together.
Suddenly the conductor shouted, "Clapham"
and Kekule came to with new ideas of structure formed in his mind.
Kekule raced to get his concept into print.
Couper's boss had been slow to get his paper published,
so Kekule took all the credit.
And in science there's no prize for second place.
Despite having been the first to unravel carbon's secrets,
Couper got none of the glory.
When he discovered that his boss, Adolphe Wurtz had somehow
delayed in sending his paper,
he flew into a rage at Wurtz, who promptly expelled him from the lab.
From there, he disappeared completely from chemical history.
No scientific papers, no letters to journals, no experiments, nothing.
Couper missed out on his chance for recognition
and soon after lost his mind.
He would spend years in an asylum.
But once carbon's secrets had been revealed,
a world of opportunity beckoned for many others.
There are more known compounds of carbon
than of any other element,
so understanding how it could combine gave us the means
of creating compounds by design.
Suddenly it seems everyone was manipulating the elements
so it wasn't long before industry
was cashing in on this new found certainty,
and modern, industrial chemistry was born.
Combining elements into new compounds would not only offer
the prospect of building fortunes,
science's mastery of carbon chemistry began to shape our lives.
It's hard to imagine a world without plastics today.
One, invented in 1907 had the catchy title of
polyoxybenzylmethylenglycolanhydride better known as Bakelite.
It soon appeared almost everywhere.
The wonder material could be moulded into a myriad of different shapes.
New discoveries came thick and fast.
In the 1930s, American Chemist, Wallace Carothers
tapped into a mass market.
He converted carbon chemistry into cash
when he invented what's in here.
It looks a bit like a cocktail, at the bottom is a carbon chain,
hexamethylenediamin. That's "hexa" for hexagon.
Six carbon atoms.
And floating above it is another carbon chain,
decanedioyl dichloride.
And on the boundary between the two chemicals
they're reacting together to form bonds.
So if I pull out this glass rod,
I make a string which is more and more of the chemicals
bonding together into very long chains.
I'm going to make use of this device as a spinning wheel.
With just a few elements, carbon,
nitrogen, oxygen, and hydrogen, found in coal, water and air,
Carothers had designed
his very own unique fibre.
It could be spun as fine as a spider's web,
but had the strength of steel.
It was called Nylon.
When nylon stockings first went on sale in America,
the entire stock of 5 million was sold in a day.
Nylon began a revolution in synthetic chemistry,
but Carothers didn't live to see its success.
He suffered from depression
and just three weeks after the basic patent for Nylon had been filed,
at the age of 41, he committed suicide
by slipping a carbon compound, potassium cyanide, into his drink.
Nylon became a global phenomenon, progress appeared unstoppable.
But inevitably, perhaps,
our increasing control of the elements brought new dilemmas.
The automobile was just 35 years old
when Thomas Midgley Junior, an engineer with General Motors,
found a chemical remedy to help its engine
run smoothly and more efficiently.
Cars at that time had terrible trouble
with their engines knocking and misfiring.
Midgely had tried to solve this by experimenting,
it's said, with everything from butter
and camphor to ethyl acetate and aluminium chloride.
Success finally came with a lead compound,
tetra-ethyl lead, known as TEL.
It worked brilliantly, nothing else came close.
By the 1970s, the US alone
was adding around 200,000 tonnes of lead to its petrol every year.
But research was emerging to suggest that it was causing harm,
both to humans and the environment.
In 1983 a Royal Commission questioned whether
"any part of the Earth's surface
"or any form of life remains uncontaminated".
Midgley's compound began to be phased out.
Today almost all of the world's petrol supplies are unleaded.
Lead.
The alchemists thought it was the oldest metal.
The Romans were the first to use it on a large scale.
It is so stable that Roman lead pipes still survive to this day.
Our word "plumbing" comes from the Latin word for lead, plumbum.
Lead is toxic to humans as it deactivates the enzymes
that make haemoglobin in blood.
Although no longer used in petrol,
much of the lead produced each year still ends up in cars, in batteries.
Lead may have forced scientists to face difficult questions,
but it didn't stop them forging ahead
in their bid to control and manipulate the natural world.
And their work with one group of elements was to spark a
revolutionary idea - the prospect of creating new, manmade elements.
It was a concept that would shake the foundations of chemistry...
EXPLOSION ..to its core.
At its heart, were the radioactive elements.
In 1896, French scientist Henri Becquerel
was working with uranium crystals
and found ultraviolet light made them glow.
It looks eerie.
He left uranium salts overnight
on a photographic plate that had never been exposed to light.
In the morning, he found a dark shadow on it
and realised that the uranium salts must have been the source of energy.
Bequerel had discovered radioactivity.
Scientists began to investigate.
One was a young Polish chemist, Marie Curie.
Marie began collecting uranium ore, called pitchblende.
CLICKING
Testing it with an electrometer,
she found... RAPID CLICKING
..that it was four times more radioactive than pure uranium.
She checked it 20 times. What could be going on?
Then she had a brainwave, she decided there was
something else in the pitchblende that was boosting its radioactivity.
Something more radioactive than uranium.
But what? Could it be a new element?
Marie Curie didn't have a well-equipped lab,
it was far more basic.
A bit like this.
One chemist called it a cross between a horse stable
and a potato cellar.
She had a tonne of pitchblende, some say 10 tonnes,
delivered by horse and cart.
And then with just basic equipment like this,
she attempted to isolate her mystery elements.
Her experiments had a myriad of complex stages, including
potentially lethal processes using highly flammable hydrogen gas.
But all her hard work was worth it.
With just her primitive kit,
Marie Curie discovered two radioactive elements.
Polonium, named after her native Poland
and another that would launch an entire industry, radium.
Radium was once the key component in luminous paint.
It's intensely radioactive.
The world fell in love with radium,
assuming its invisible energy must be good for you.
The French slapped on Radium face powder.
The Germans ate Radium chocolate.
The Americans wore Radium branded condoms.
But the magic faded when doctors realised
that far from boosting health, it triggered cancers.
Marie Curie didn't live to see the amazing journey
the radioactive elements would take us on.
Because whilst they're naturally occurring elements,
they would take man one step closer to a seemingly impossible dream.
To create entirely new elements.
Ernest Rutherford was working with radioactivity to investigate
the subatomic world, when he made an astonishing discovery.
At the beginning of the 20th century,
it was widely believed that atoms never change.
That carbon atoms will always be carbon atoms, gold always gold.
Well, Rutherford overturned this idea
by taking a great leap forward in scientific thinking.
I'm surrounded by some of the original equipment used by
Rutherford and the early pioneers to unlock the secrets of the atom.
Rutherford had concluded that the atom was mostly empty space,
with tiny electrons buzzing around a central nucleus containing protons,
positively charged particles.
Protons are vital to an atom's identity.
The number of protons gives an element its uniqueness.
Carbon atoms have six protons in their nucleus.
Seven means nitrogen.
Rutherford came to the shattering conclusion
that the number of protons in the nucleus of a radioactive element
could change because it decayed.
Rutherford realised some of the mysterious radioactivity
was actually miniscule fragments of atoms containing protons,
which were being fired out of the nucleus.
He named them alpha particles.
Much as life forms break up and decay,
so some elements themselves break up, radioactive decay.
As the tiny chips of the atom, the alpha particles, fly off,
its nucleus shrinks.
Rutherford realised that as the nucleus loses protons,
the atom's identity changes.
It turns from one element into another.
We can glimpse radioactive decay in a cloud chamber.
If you look carefully, you can see trails of vapour
which are caused by alpha particles
being spat out from the source.
Now they are incredibly tiny,
they're a hundred thousandth of the width of a single atom.
They show radioactive decay.
Rutherford was studying this when he suddenly realised
that it could transform the atom of one element
into the atom of another.
So if that happened naturally,
could it also be made to happen artificially?
Could Rutherford deliberately create one element from another?
Rutherford loved simplicity,
and this simple piece of kit was his basic apparatus.
He introduced a radioactive source at this end
which blasted alpha particles toward the screen on the far end.
When he filled the chamber with nitrogen,
he saw flashes that weren't from the alpha particles.
Rutherford suspected that a change was taking place.
Now, the nucleus of nitrogen contains seven protons,
whereas an oxygen nucleus has eight protons.
Now, in Rutherford's experiment he was firing alpha particles,
each one containing two protons,
and these alphas were colliding with the nitrogen.
This is where the alchemy takes place.
Because the collision knocks out a single proton,
these were what were causing the flashes on the screen.
But what's left behind is now no longer nitrogen.
The extra proton it's gained means that it has transmuted into oxygen.
The small flashes on Rutherford's apparatus
proved an explosive moment in science.
Turning nitrogen into oxygen was as weird as stroking a cat
and having it suddenly turn into a dog.
A fire can reveal how different these two elements are.
This is liquid nitrogen.
See what happens when I pour it on the fire.
The fire goes out.
This is liquid oxygen.
It burns much more brightly.
Rutherford had turned one element into a completely different one.
Scientists had previously believed
elements were fixed and unchangeable.
Now, Rutherford had proved that they could be transformed.
This suggested another intriguing possibility.
Rutherford's work, turning one known element into another,
gave scientists hope that they could turn an element
into a completely new one.
For many years progress was very slow
because they simply didn't know enough about the atom.
Then in 1932, here in Cambridge, a crucial part of the atom was found.
James Chadwick discovered neutrons.
These are particles without an overall positive or negative charge,
that along with positively charged protons, make up the nucleus,
the heart of the atom.
Italian scientist, Enrico Fermi, saw the potential of the neutron
in the quest to make brand new elements.
The team who worked with him thought he was infallible
and nicknamed him "The Pope".
Fermi's big idea was to create a new element,
one beyond the end of the periodic table.
Further up even than uranium,
the heaviest naturally occurring element on Earth.
If Rutherford could turn nitrogen into oxygen,
Fermi wondered what would happen if uranium was made heavier still,
by adding more protons to its nucleus.
Could he go beyond nature and create a new element?
Fermi experimented on uranium
using Rutherford's technique of pounding the nucleus.
Others had also tried using positively charged alpha particles,
but so far no-one had succeeded in creating new elements.
Then one day when Fermi was playing tennis,
he realised where the other scientists were going wrong.
He was hammering away at the tennis balls
when he suddenly had a moment of true clarity.
He knew that the nucleus of the atom is positively charged
as are the alpha particles.
So they tend to repel one another making it highly unlikely
for the alphas to enter the nucleus. But then,
it occurred to Fermi that if he used neutrons,
particles with no charge,
then the nucleus wouldn't repel them,
making it much more likely that they would be able to penetrate it.
So in 1934, Fermi began to experiment
by shooting neutrons at the nucleus of uranium.
Fermi was hoping that when the neutron entered the uranium nucleus,
it would make the whole thing unstable.
The nucleus likes to be balanced, so if it has too many neutrons,
it will convert one of them into a proton,
spitting out an electron.
Fermi reasoned that this would increase the number of protons,
giving him a brand new element.
As he ran the experiment, Fermi found elements he didn't recognise.
So what were they?
He worked his way down the periodic table, checking for known elements.
He tested for radon, actinium, polonium, all the way down to lead.
The new elements were none of these.
So in 1934 the man they called the Pope
made a leap of faith.
He proclaimed to the scientific world
that he'd created elements heavier than uranium.
Scientists were electrified and began to investigate Fermi's claim.
In 1938, a team of German scientists led by chemist Otto Hahn
decided to repeat Fermi's work.
Only they quickly found
that his claim to have created a new element was wrong.
They identified one of his elements as barium
which has 56 protons in its nucleus
compared with the uranium he started with which has 92.
Hahn was intrigued.
It's as though uranium had been split in two.
Hahn wrote of his confusion to a colleague, Lise Meitner,
who was working in Sweden at the time.
As an Austrian Jew, Meitner had recently fled Nazi Germany
and was spending Christmas 1938
at the seaside with her nephew, Otto Frisch.
Meitner puzzled over the mystery
and together with Frisch she considered the uranium nucleus.
Because it's a relative giant it must be quite unstable.
Then they started to think about water droplets,
and Meitner imagined the uranium nucleus
like a very wobbly, unstable drop
ready to divide with the impact of a single neutron.
She suddenly realised that the uranium's nucleus had split in two.
Both Fermi and Hahn had witnessed what we now know as nuclear fission.
Then Meitner worked through the calculations.
She reckoned that the combined mass of the two fragments
was slightly less than the mass of the original uranium nucleus
by about a fifth of one proton.
She wondered what had happened to this missing mass.
Then it slowly dawned on her.
Einstein's famous equation e=mc2.
The missing mass had been converted into pure energy.
Meitner's flash of insight heralded the creation of the nuclear age,
where exciting possibilities for a new form of energy
would be countered by its potential for weaponry.
This site at Orford Ness used to be a military testing ground,
one of the most secret places in Britain.
Back in 1939, Lise Meitner's work on nuclear fission
was published as war cast a long shadow across Europe.
It shook not just the scientific community,
governments who stood on the brink of conflict
became aware of the extraordinary power
that could now be wrought from an element.
On both sides of the Atlantic, scientists were scrambled to
investigate the potential of this new discovery.
The result was the US led Manhattan project.
Its aim was to produce the first atomic bomb.
Using scientists from America,
Canada and Europe, the 2 billion project's rapid progress
was fuelled by fears that Nazi Germany
was investigating nuclear weapons of its own.
Both the Germans and the Allies knew that the uranium nucleus could be
split by bombarding it with neutrons to release a huge amount of energy.
But to be effective,
that energy needed to be released almost instantly,
a slow reaction would produce a uranium fire but no bomb.
So both sides poured their efforts into perfecting
the key to a rapid energy release on a grand scale.
A chain reaction.
Imagine this ping-pong ball is a neutron,
flying towards an unstable uranium nucleus, a mousetrap.
It sets off the mouse trap
which in turn forces a new neutron into the air.
Now in a chain reaction, this is what would happen.
One neutron to set it off,
but loads of mousetraps of uranium primed and ready.
Now imagine each mousetrap of uranium releases a
blast of energy, that same energy that Lise Meitner had calculated.
The resulting blast would be enormous.
In 1942, Italian physicist, Enrico Fermi, now living in America,
became the first man to unleash uranium's chain reaction.
Uranium.
It harbours the power not only to win wars
but to electrify millions of homes.
Before its radioactive secrets were revealed,
this element's glow under ultraviolet light
made uranium glass a desirable asset.
About seven weeks worth of your year's electricity
comes from nuclear fission part fuelled by uranium.
And it's used in tank shells
as its great weight allows it to drive through armour.
But processing uranium for bombs was both difficult and costly.
America would need to come up with a suitable alternative
to create its nuclear arsenal.
In California, scientists were focussing on trying to create
a new element heavier than uranium.
The key to this was a machine called a cyclotron
which gave rise to this giant machine, a synchrotron.
Both machines operate on the same principle.
They use huge magnets to steer charged atoms round and round,
faster and faster.
The magnets are so powerful that if one of them was switched on,
it could rip a sledgehammer straight out of my hands.
Now, the way to make a new element is to
increase the numbers of protons in a nucleus of an existing element.
And in a cyclotron, the way this was done,
was that when the charged atoms
reached a tenth of the speed of light,
they were steered and smashed into a metal target,
with the potential to create a new element.
Finally, man's dream of creating a building block from
beyond the end of the periodic table was about to be realised.
American physicists, Edwin McMillan and Philip Abelson,
blasted uranium with a beam of particles to create element 93.
They named it Neptunium.
The first element heavier than uranium to be created by man.
Chemists were once limited to using the elements nature provided.
Now science breached this frontier, creating synthetic elements.
And, with this new power would come new dilemmas.
In 1941, the next element to be forged by mankind
would become infamous...
it was called plutonium.
Scientists quickly realised that
plutonium was capable of undergoing nuclear fission
in a way that could fuel an explosive chain reaction
and it was soon being made into a bomb.
The discovery of nuclear fission to the creation of the first atom bombs
took less than 7 years.
And on August 6th, 1945
the full accuracy of Lise Meitner's scribbled calculations was revealed.
1,900 feet over the Japanese city of Hiroshima,
one piece of Uranium 235 was fired into another,
causing a rapid chain reaction.
Just over half a gram of mass was converted into energy,
that's one tenth of a 10p coin.
But it exploded with a force equal to about 13,000 tonnes of TNT.
Three days later, Nagasaki was hit by a plutonium bomb,
bringing the death toll from the two bombs to an estimated 200,000.
Plutonium.
It was named after the planet Pluto
and also shares its name with the Roman god of the underworld.
Bombarding Uranium 238 with neutrons creates this powerful element.
A gram of plutonium has same energy as a tonne of oil.
Many of the Cold War's nuclear bombs contain plutonium.
The first man made objects destined to leave our solar system,
the two Voyager space probes,
are powered by plutonium.
The dream of turning lead into gold is what drove the early alchemists.
And the dark race to create the atom bomb was a kind of modern alchemy.
The war had revealed the frightening power of these unstable elements.
But they had offered a tantalising glimpse
into their infinite possibilities.
The lure of scientific discovery, of creating entirely new elements
at the extremes of the periodic table had proven irresistible.
The thirst to create yet more elements drives the physicists
at the GSI Helmholtz Centre for heavy ion research
in Darmstadt, Germany.
Their mission is to reach the limit of chemistry,
to find the ultimate element
which will stretch the laws of physics to their boundaries.
So far, they have made six new elements.
The latest confirmed is element 112, which they've named Copernicium,
after the astronomer Copernicus.
And this is where it all starts,
in one of the world's most powerful nuclear accelerators.
Scientists are using the high-tech equipment
behind this 70 tonne lead door
not only to make some of the heaviest elements ever created,
but to study their properties,
to try and understand their characteristics if you like.
They're attempting to finish the work
that chemists like Mendeleev started
and to discover the secrets at the outposts of the periodic table.
But they first have to create the new elements.
This is the control centre for the giant accelerator,
which is essentially a gun for firing one element into another.
This small piece of zinc
is identical to the sample used in the accelerator.
Charged atoms of zinc are fired towards a lead target.
Nearly 50 million volts of electricity
accelerate these atoms towards the target so that when they collide,
they are travelling at 67 million miles an hour.
That's nearly 4,000 times faster than the space shuttle.
The idea is that at this speed
there's a chance the atoms might fuse together,
creating an atom of a new element.
In this case, element 112.
But it's obviously not as simple as it sounds.
Too much energy and the colliding atoms break up
too little and the new element isn't created at all.
In fact, even with the perfect energy
the chances of union are remote.
It's a bit like you winning the lottery
with 3,000 balls to choose from rather than just 50.
Beating these enormous odds,
scientists have created new, single atoms,
so unstable they only exist for seconds.
But that's still long enough to determine some of their properties.
In tests, element 112 has proven volatile and unstable
and it reacts a little like mercury.
It would be liquid at room temperature if enough were made.
Because of that similarity its creators realised it should be
positioned just beneath Mercury on the periodic table.
Physicists here are becoming the new chemists.
Soon they'll be attempting to create element 120.
The discoveries made here at GSI may seem distant, even arcane
but it's vital to push the periodic table to its limits.
Without studying these man made, highly unstable elements
we may never fully understand the story of our universe.
My journey began with those alchemists whose daring experiments
led to the discovery of many of the elements.
They paved the way for the early chemists
whose mission to find out what the world is made of led to
them splitting matter and bringing order to the seemingly random chaos
of the elements, culminating in the creation of the periodic table.
Scientists were able to use these discoveries
and the ordering of the elements to build the modern world.
Finally, they could command nature's building blocks to their will.
But our story is still far from finished.
The fleeting glimpse we've had
of the exotic outposts of the periodic table
gives a hint to what the story of the elements may yet hold.
Their possible reactions,
their properties, their unimagined potential.
And that is what scientists now have to work on,
to reveal the secrets the elements have so far refused to surrender.
What's so exciting is that no-one knows where that part of this
astonishing story may yet take us.
Subtitles by Red Bee Media Ltd
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