Original subtitles

Narrator: August 6, 1945.

The first mission of its kind.

Morris Jeppson: The last person to have his hands on

that weapon was me.

Narrator: A devastating new weapon is unleashed on the

city of Hiroshima.

Within weeks, the US government mobilizes teams

of scientists and soldiers to assess the damage.

Directly from the pages of their report, the science

of the first atomic bomb, as told by the men who

analyzed the effects of the explosion and the survivors

who experienced them first-hand.

Takashi Tanemori: All of a sudden bang, flash in the sky.

Narrator: Now, what happened in the 24 hours

after the world's first atomic attack.

Morris Jeppson: On August 6th, 1945 I was 23 years old.

I was on board the Enola Gay B-29 flying to Japan.

Shigeko Sasamori: 1945 August 6.

I was 13 years old.

Takashi Tanemori: On August 6th, 1945, I was standing

against the window looking outside.

Koko: On August 6th, 1945, I was 8 months old baby.

And this is the dress I was wearing that day.

Narrator: A day earlier, at a military base on Tinian

Island in the pacific, the world's first combat atomic

bomb is brought out on the tarmac in preparation for

delivery.

The weapon's code name is Little Boy.

Its conception is the most covert operation ever

undertaken by the US Military.

Some say it holds the power of the sun, the stars, the

cosmos.

But for the crew, the bomb looks like something much

less cosmic.

Morris Jeppson: Little Boy was, ten feet long.

A weighing more than the biggest pick up truck you

can buy.

Narrator: Morris Jeppson, is one of twelve Enola Gay

crewmembers, whose mission is to drop Little Boy on a

yet to be identified Japanese city.

At 2:45am, almost 12 hours after loading the four and

a half ton cargo, the mission officially begins.

The Enola Gay takes off and heads west toward Japan.

Morris Jeppson: The first time I saw, Little Boy, was

when I climbed in to the bomb bay.

Narrator: Within this cylinder of armored steel

is 140 pounds of highly enriched uranium.

It's uranium is divided into a projectile and a

target.

The bomb works like a big gun, bags of gunpowder

ignite, creating the pressure to send the

projectile flying forward, smashing it into the

target.

Within seconds, critical mass creates a nuclear

chain reaction releasing a colossal amount of

destructive energy.

But because B-29s are known to crash on take off, the

gunpowder is not yet inside the bomb.

Now that they're safely off the ground Jeppson and

Captain Deke Parsons can put the explosives into

place.

It takes Parsons only 15 minutes to place the four

bags of cordite gunpowder inside the bomb's tail.

But Little Boy's detonation system is not yet fully armed.

That's Morris Jeppson's job.

These are the actual plugs he used that day to arm the

Little Boy bomb.

The weapon has three green plugs that work like a

safety lock on a gun, preventing it from

activating.

Jeppson must remove the green plugs and swap them out.

The red plugs complete the weapon's electrical

circuitry so that sparks can ignite the gunpowder.

Morris Jeppson: I had to handle, touch, lean on the

Little Boy bomb.

So the last person to have his hands on that weapon

was me.

Narrator: With the last red plug in place, the bomb is

now alive.

There are less than two hours before they reach

Japan yet no one's completely sure that Little

Boy will actually work.

Morris Jeppson: The Hiroshima bomb was an

experimental weapon and it was the first test.

Narrator: Three Japanese cities had been chosen as

potential targets for the attack.

The primary is the port city of Hiroshima located

on the delta of the Ota River.

A city of considerable military importance, it

houses a communication center and an assembly area

for troops.

But it's far from just a military target.

Eighty percent of the people here are civilians.

Since the previous March of 1945, almost every major

city in Japan has been fire-bombed yet Hiroshima

remains untouched.

Richard Richard Rhodes: The people of the city worried

about that.

Were they being chosen for something especially terrible?

Narrator: But as the Enola Gay reaches Japan,

Hiroshima's fate is still not final.

It all depends on the weather.

One of the requirements for the target is that it has

to be visible from the air.

Weather planes fly ahead to check the conditions over

the three selected cities.

As it happens it is a clear morning at Hiroshima.

The city's fate is now sealed.

Narrator: Thirteen-year-old Shigeko Sasamori can feel

the sun burning down on her on this hot, cloudless

morning.

She runs to join schoolmates in their

assignment to clear the streets for firebreaks in

case of attack.

Shigeko Sasamori: I look up the sky, I saw the

beautiful silver airplane and the white long tail and

the blue sky.

It looks beautiful.

And same time I saw something drop.

Narrator: Shigeko is less than a mile from the Enola

Gay's target, the distinctive T-shaped Aioi

Bridge.

Running across the river in the center of downtown, it

can be spotted easily at even 32,000 feet.

90 seconds before release, the Bombardier sets his

sights on the target about two miles below, and makes

careful last-minute manuevers.

Will they hit the target, and will it explode at the

pre-set altitude of 1900 feet over the city?

Morris Jeppson: There are hydraulic actuated doors,

big long doors 12, 15 feet long, they don't just

slowly open.

They fly open like that.

Narrator: Jeppson and fellow crewmembers had done

the math and expect the bomb to detonate at 42

seconds.

Morris Jeppson: At 43 seconds I was nervous.

I was monitoring the test box.

Thinking and counting in my head.

Narrator: The crew of the Enola Gay are not the only

ones counting down at 8:15 on August 6th.

Eight-year-old Takashi Tanemori, left home at 8am

to get to his school.

He's looking forward to playing with his friends.

Takashi Tanemori: I was excited this particular

morning for the hide and seek because I was chosen

as it.

So I was standing against the window looking outside.

Narrator: While Takashi counts, thousands of others

are outside, on route to work and school.

As the lone Enola Gay flies overhead there's little alarm.

It looks nothing like the bombing squadron most

people fear.

Richard Rhodes: People assumed it was a weather

plane, and instead of doing what the scientists had

assumed would happen which is they would run into bomb

shelters and be safe from the effects of the blast.

People came outdoors to look.

Takashi Tanemori: All of a sudden, bang, flash in the

sky, pure white.

I saw the bones in my fingers as though I was

looking at an x-ray.

So intense.

Narrator: This is the only footage ever taken of this

atomic explosion, scant documentation of an event

that changes the course of history.

Within moments, the mushroom cloud is 10 miles

high.

It spreads 3 miles over the city and its more than 350

thousand inhabitants.

On the day of the attack, the United States has been

in the war for 4 years and has lost over a hundred

thousand men on the pacific front alone.

Despite losing over a million men the Japanese

continue to fight fiercely.

Some fear that if the war goes on millions more will

be lost on both sides.

Richard Rhodes: We thus saw the atomic bomb as a

potential way to shock them into surrender.

Narrator: This radically new bomb reduces the

living, breathing downtown of Hiroshima to a

wasteland.

70,000 human beings are dead instantly.

Another 70,000 injured.

It's the highest death toll ever caused by a single

weapon.

Yet Japan continues to fight.

Three days later, on August 9th,

the United States drops a second

atomic bomb.

This time on the city of Nagasaki.

Another 40,000 die.

Japan formally surrenders three weeks later.

The world's bloodiest war is finally over.

Narrator: Just weeks after Japan's surrender, President

Truman orders a report on the physical and medical damage

inflicted by this new weapon.

Hundreds of scientists, engineers and military

personnel are recruited for the job.

Alongside occupation forces, special

investigative teams arrive in Hiroshima.

Working with Japanese scientists, they'll spend

10 weeks amidst the ruins gathering intelligence.

To comprehend the bomb's devastating power, the

analysts break down the three major effects of the

atomic explosion.

Upon detonation, an explosion of energy is

released into a small volume of air.

This creates a searing, white-hot fireball that

flashes hotter than the surface of the sun.

Gamma rays and neutrons from the break-up of

uranium shoot outward as deadly invisible radiation,

as the fireball stops expanding, a wall of

pressure or blast wave, races out at more than 700

miles per hour.

In their report, the scientists describe the

effects of the first stage of the explosion, a thermal

flash.

It generates temperatures of 7200 degrees Farenheit,

twice the melting point of steel.

Because there's so little film footage of the

explosion in Hiroshima, scientists look to atomic

tests, to help them measure the intensity of the heat.

Ted Postol: When the weapon detonates, an enormous

amount of energy is released in a very short

period of time, and a very large amount of the energy

is released simply in the form of light and heat.

The temperatures get extremely high.

Perhaps tens of millions of degrees.

It's as if somebody could reach down into the center

of the sun and place it in the atmosphere and let it

release its energy.

Narrator: This energy is instantly lethal when

released upon human beings.

Ted Postol: If your skin gets illuminated it will

simply be turned into carbon.

And in the case of people who were close enough to

get that much light and heat on their bodies, they

simply ceased to exist as living entities without

them probably even being aware that anything had

happened.

Narrator: It's impossible to know exactly how many

citizens are turned into simple piles of carbon

during those first few seconds.

The US Military maps the casualties.

Within a radius of eight hundred feet from ground

zero, almost no one survives.

Some, exposed directly to the rays of the fireball

seem to vanish completely.

What remains are now called atomic shadows.

These imprints of both people and objects can be

found all over Hiroshima.

Ted Postol: What happened was that the light from the

fireball shined on the ground and it caused the

concrete to actually darken.

The light from the fireball was intercepted by this

railing here, and so this bright area was not exposed

to the extreme light of the fireball.

Narrator: These Atomic shadows give scientists a

tool to analyze the location of the explosion.

Ted Postol: And this allowed people to measure

the direction and the height of burst of the

nuclear weapon because they could form a plum line and

from many different directions you can actually

get the location of the nuclear explosion.

Narrator: From their calculations, the

scientists discover the Enola Gay hit incredibly

close to the target, just 550 feet, less than two

football fields away from the t shaped bridge.

More than 50% of those killed within a half-mile

of ground zero died of severe burns.

Those who survive at that distance are barely alive.

This man is suffering from the type of burns that

plague Shigeko Sasamori.

The flash burns over two thirds of her body.

The little girl who had left the house that morning

is unrecognizable to her mother when she finds

Shigeko 5 days after the blast.

Shigeko Sasamori: She heard my voice but it didn't look

like me.

Because my face and hair was like a big black football.

All round and where is the nose where is the eyes.

Couldn't tell all black.

Man: Clothing ignited, thatched roofs of houses caught fire.

The flash heat was intense enough to cause fires

despite the distance of the fire ball from the ground..

Narrator: Anything exposed to the heat of the flash, a

child's notebook, newspapers, the traditional

paper soji screen, ignite instantly.

Temperatures higher than 3200 degrees Fahrenheit

fuse even roof tiles into unrecognizable shapes.

Richard Rhodes: This intense flash of light,

burned granite, burned steel, burned iron and glass.

Whether you lived or died depended on how far away

you were from ground zero.

It didn't matter if you were Japanese or Martian.

This was not an ideological bomb.

This was a weapon of mass destruction, a weapon of

terror.

Narrator: Less than a mile from ground zero is the

3-story school building where Takashi is playing

hide and seek.

The bomb's shockwave is about to hit.

Takeshi Tanemori: I do not know exactly how it

happened but our school building collapsed.

The blast singed the left side of face I do not know

how long under the debris.

Pitch dark.

You cannot see anything.

Even my hands from my nose I could not see.

Narrator: Takashi is not alone.

There are thousands trapped beneath the rubble that was

once downtown Hiroshima.

Narrator: The blast wave created by the Little Boy

atomic bomb flattens the city in less than 10 seconds.

Male Military Voice: Over 60,000 buildings were

destroyed or severely damaged by the atomic bomb.

This represents over 67% of the city's structures.

Narrator: A full minute after detonation the force

of the shock wave jolts the crew of the Enola Gay, 9

miles away, 29,000 feet in the air.

Morris Jeppson: There was a slapping effect on the

airplane it was the passage of a shock wave.

And ok that's expected.

And then a few seconds and another smaller slap and I

don't' think anybody on the airplane knew what that was.

Narrator: That second hit means the bomb has exploded

as planned, 1900 feet above the city.

To understand the dynamic forces of shockwaves, blast

simulations are captured with high-speed photography.

Upon explosion, a super-heated bubble of air

violently pushes outward, creating a shock wave.

Ted Postol: Now this shock wave as it expands outward

will reach the ground and reflect off the ground,

creating a combination of a reflected shock and a

primary shock and so on the ground you will do much

more damage than would otherwise be the case from

the individual shocks.

And this is why the attackers of Hiroshima and Nagasaki

chose to detonate a weapon a couple thousand

feet off the ground, basically to

maximize the destruction to the target.

Narrator: If Little Boy had been dropped on the ground

the earth would have absorbed most of its

energy.

But detonation in the air forces the shock wave out

flattening just about everything in its path.

There is heavy damage for three miles in every

direction.

More than a half a century later, the once devastated

city of Hiroshima is completely rebuilt.

Few visible scars remain from the bombing.

But there is one building that stood almost directly

under the bomb's detonation and it is still here today

as a symbol of peace.

Once an exhibits building for local business and

government, everyone inside was killed instantly.

But the building still stands.

Ted Postol: The dome was built of copper and copper

melts at a low temperature, light from the fire ball

was so intense that it basically melted the copper

before the shockwave arrived.

The shock wave came down vertically blew through

this opening and just knocked each floor down as

it propagated through.

So this building is standing because of the

peculiar accident that it was almost directly under

ground zero.

Narrator: Windows and flying debris become

shrapnel as far as 12 miles away from the blast.

The damage from the explosion is well

documented after US troops arrive but on August 6th

the violence of the moment is captured only in the

survivor's memories.

Many of Hiroshima's survivors have painted

those first hours.

Years later, Takashi Tanimori also wrote about them.

Takashi Tanimori: Beneath the heap, I lay buried on

my back, unable to move.

Narrator: Trapped less than a mile from ground zero,

Takashi can no longer hear the cries of help from his

classmates.

A young soldier digs him out from beneath the rubble.

But he's not out of danger yet.

Takashi Tanemori: The soldier carrying me weaved

in and out of throngs of people who were screaming

in agony, charred, dead or just barely alive.

Creeping, stumbling, dragging their feet,

looking for any escape the blazing inferno.

Narrator: The military analysts studying the destruction

report the beginning of a rare phenomenon.

Man: In Hiroshima fires sprang up simultaneously

all over the wide flat central area of the city.

Richard Rhodes: People don't seem to understand

about this bomb that it's main effect is fire.

It's not as if a bomb started a fire in one

corner of a street and the fire slowly worked its way

up to the other corner.

Everything was lit instantaneously.

Narrator: These small flames represent the many

fires burning in Hiroshima.

Fires that were set not only by the initial flash

but also by the collapse of gas lines and broken

cooking stoves.

The fires could be seen by the Enola Gay's crew from

almost 30,000 feet above the city.

Richard Rhodes: What they saw really rather horrified

them.

Morris Jeppson: Down on the ground was a spreading mass

of flickering lights, which had to be flames of things

burning.

Richard Rhodes: There were fires everywhere.

One of the crew said, "I looked for a while and

counted for a while and then I stopped counting."

Morris Jeppson: Now the comprehension of what was going

on down there was settling on people's minds, including

mine, that there was bad destruction and loss of

life down below.

And the hope in everyone's mind was that the explosion

was of magnitude that it might affect the end the

war which it did.

Narrator: The flaming points of light below the

Enola Gay are about to turn into something much worse.

To see what happens when many small fires are set

off simultaneously, Hughes Associates, a group of fire

protection engineers, designed a simulation.

Jason Floyd: First the fire will be very small and

eventually we'll start to see an effect developed as

what happened at Hiroshima.

Think of it as rather than being cylinders to being

city blocks of burning buildings.

In the city is you have uneven terrain, you have

hills, you have buildings of different sizes so you

have uneven airflow we've set up these sheets of dry

wall with gaps in them to sort of represent this idea

of having uneven terrain which is going to introduce

a bit of a swirl into the flow feeding the fire.

Narrator: The heat of the flames sucks in air from

the ground.

This creates gale force winds of up to 50 miles per hour.

Jason Floyd: At points of time over the city you

would have had "fire whirls" these tornados of

flame which would appear and disappear as the air is

entrained into the fire and forms these vortexes, much

like a dust devil on a hot summer day.

Narrator: Whether flames from candles, canisters or

city blocks, the fires merge as the heat and winds

become more intense.

In Hiroshima the mass fire burns for 6 hours and

consumes 4 and-a half-square miles.

What remains is what survivors call a "city of death."

Shigeko Sasamori: Hiroshima city was red ocean, red

ocean fire burning whole entire city is burning.

Narrator: The rivers of Hiroshima are one of the

only safe havens for survivors seeking safety

from the heat and flames.

Despite her serious burns, young Shigeko Sasamori makes

it to a river bank, only to be surrounded by

death and suffering.

Shigeko Sasamori: I heard a baby screaming.

I still remember very clearly the mother was

bleeding all over and, and tried to nurse baby and

baby was so , when I remember that part of it I

just can't take it.

Narrator: The river is choked with floating

corpses.

Many of those still alive are barely recognizable.

Shigeko Sasamori: People themselves just horrible

looking, the hair with ashes, and kinked up, and

some were skin hanging on.

Just dead people walking, like a ghost.

Gusterson: Eye witnesses will talk about survivors

walking out with their hands in front of them,

apparently it dulled the pain of skin that was

falling off, but it also made people look like

walking ghosts.

Richard Rhodes: I remember one woman described seeing

a man walking down the road holding his eyeball in his

hand.

It's hard for us to imagine how dantesque the world was

that was created by the explosion of this beautiful

invention of physics.

Shigeko Sasamori: If there is a hell, that was a hell.

Narrator: Thousands, in desperate need of help,

have nowhere to turn and no one to treat them.

Man: Medical facilities, crowded into the heart of the

city were crippled or wiped out by the explosion.

The impact of the atomic bomb disrupted.

Narrator: The normal fabric of life in Hiroshima is shattered.

Before the attack there are more than 200 doctors in

the city, 90 percent are killed or injured that day.

Gusterson: The scale of destruction was so

enormous, it's not just the 10s of 1000s of dead and

incinerated bodies, there were hardly any hospitals

functioning, hardly any doctors functioning.

You have thousands of people dying, gravely ill

with very little infrastructure to help them.

Narrator: Of the area's 45 hospitals only 3 were usable.

But more than the city's infrastructure is wiped out.

Richard Rhodes: When you destroy a city you're

destroying an intricate web of social and personal

connections.

One of the horrors for the survivors was that their

world had been burned away.

They were left with their burns trying to decide

where the world was.

Narrator: People who had managed to survive the

attack are suddenly struck down with a mysterious

illness some called "Disease X."

Thousands of survivors report vomiting, purple

sores and hair loss in the days and weeks after the

blast.

The US Government knows it's radiation poisoning.

But they don't fully understand it.

Richard Rhodes: The only studies that had been done

prior to that time, had been done on rabbits.

There was almost no literature about whole body

exposure in human beings.

Narrator: Two years after the bomb was dropped the U.S.

government creates the Atomic Bomb Casualty

Commission, the ABCC.

Their mission is not to treat the survivors, but to

observe and study them to see what radiation exposure

would do to their health and mortality.

Koko Tanimoto Kondo was one of their subjects.

Less than a mile from ground zero, Koko was an

eight-month old baby in her mother's arms when the bomb

exploded.

Koko Tanimoto Kondo: This is area where our house was

located.

Now it's a new building It's kind of difficult to

tell but yes, this is the place.

At 8:15 I was with my mother and the house was

destroyed.

Narrator: Although Koko survived the blast and the

fire what was not known was the effect radiation would

have on her body.

In the first milliseconds of Little Boy's detonation,

electromagnetic energy, in the form of gamma rays,

neutrons and x-rays, sprays up to 2 miles in every

direction.

The waves and tiny particles, invisible and

odorless, bombard anyone exposd with cell-damaging energy.

For almost all within a half-mile, the rays are deadly.

Hugh Gusterson: Many of the survivors carry around with

them the fear that the radiation is, like, a sort

of time bomb in their bodies.

They've lived with the constant fear that they

would come down with leukemia or cancer, that

they would give birth to children with birth

defects and so on.

Narrator: Several years after her house collapsed

around her, Koko became part of the ABCC's study.

Koko Kondo: The whole world wanted to know how the

radiation affected the human body.

The best way is to check the children.

Narrator: For a decade, Koko spends one day of

every year being examined.

Thousands of survivors are still participating in what

is now one of the longest running medical studies in

the world.

The ABCC, now the Radiation Effects Research

Foundation, has collected data from over 120,000

atomic bomb survivors.

Today, with the collaboration of the

Japanese government, their information continues to

shed light on how radiation affects the human body.

Evan Douple: The reason we as mamals die

from radiation exposure is simply because cells have

DNA damage, chromosone damage and they stop dividing.

Narrator: When cells stop dividing the immune system

fails, internal organs shut down, fetuses stop developing.

The process of life ends.

But this understanding comes at a cost for

survivors like Koko.

As she hits puberty, the examinations at the ABCC

become difficult.

At 14, Koko is ushered from her private exam room to an

auditorium.

Koko Kondo: The doctor told me to go up the stage.

But the spotlight was so strong so I could not see

how many people inside, but I could hear the different

languages so I could guess this must be the doctor's

meeting.

Then doctor said, "Please take off your gown."

Puberty age.

Your body change from childhood to adult woman.

I was just so furious.

Yes August 6th, 1945 I was in Hiroshima but I didn't

started that war.

Why do I have to show almost naked body to the

people?

I couldn't tell that to my father, or my mother or my

friends, it's something deep inside for a long time.

Evan Douple: It's quite reasonable that they might

feel they were treated like guinea pigs.

But because they have been so faithful and loyal and

contributing, their legacy is that their information

is going to benefit all of mankind.

Narrator: Koko has never been able to have children,

a possible result of radiation exposure.

But her participation in the study is part of a

different sort of legacy.

The ABCC data is used to help treat others exposed

to radiation, like the victims of Chernobyl.

Koko Kondo: When I heard that, I was pleased that my

data is useful for others.

Narrator: Today scientific details about radiation

studies are freely shared internationally.

But there are other aspects of the atomic bombing of

Hiroshima that are not easy to uncover.

Secrecy has always enshrouded the world of

atomic science from the conception of the bombs

even to today.

For years, the U.S.

government confiscated and suppressed nearly all

images and first-person accounts of the bombing of

Hiroshima and its immediate aftermath.

It wasn't until 1952, seven years after the bomb fell,

that these images, the only photos taken on the day of

the bombing, were made public.

Gusterson: Military censors were aware that public

opinion back home could turn to some degree against

the bombing if they were exposed to images that are

very painful to see of what exactly the atomic bomb had

done to human bodies on a large scale.

Narrator: While the military didn't want to share details of

the aftermath with the public, they did want to

understand the power of these new weapons.

And they used film footage of later atomic tests to do it.

The footage showed not only effects of the heat ray and

shock wave on different materials and structures,

but by studying the explosion itself, analysts

could measure a weapon's distance and yield.

Many of these films were placed under lock and key

and to this day remain classified.

The military analysts, who witnessed the enormous

scale and chilling effects of atomic weapons, close

their report with a grim observation.

Man: There is no more forceful argument for

peace than the sight of the devastation of Hiroshima.

Ted Postol: These weapons, they are so indiscriminate.

They are so murderous.

You have to ultimately conclude that these are

weapons of mass genocide.

Narrator: By the mid-1950s the US military was in a

global nuclear arms race with the Soviet Union, and

was testing nuclear weapons up to 1000 times more

powerful than those used on Japan.

Richard Rhodes: We're balanced on a knife-edge.

And until we get rid of all the nuclear weapons in the

world and keep it that way, we're always going to be

balanced.

In fact even without nuclear weapons we're

always going to be balanced on the knife-edge because

we know how to make them.

Narrator: Today, it's difficult to see evidence

of the once-devastated Hiroshima.

The museums and monuments of Peace Park are a

reminder of what happened on August 6th, 1945.

Inside this mound are the remains of thousands bodies

not recognizable and never claimed.

But the most powerful reminders come from those

who survived the only ones who can tell us what it's

like to live through an atomic attack.

Koko: Only one bomb changed the whole thing.

We have to learn.

We cannot make the same mistake.

No.

Takashi: The greatest way to avenge your enemy is by

learning to forgive.

I hope I am able to give my children a better world

than I received, by telling the story, the lessons that

we have learned, so that's my desire.