50 Fun Facts About Hiroshima and Nagasaki

How many Japanese cities had conventional bombing already devastated before the atomic attacks?

The campaign included the great Tokyo raid; the atomic bombings remain the only uses of nuclear weapons in war.

What was the code name of the uranium gun-type bomb dropped on Hiroshima?

Fat Man, the Nagasaki bomb, was a plutonium implosion weapon; Thin Man was an abandoned plutonium gun-type design.

Roughly how much did the Manhattan Project cost, in the dollars of the day?

It employed more than 125,000 people at its peak, with bomb design carried out at Oppenheimer's Los Alamos Laboratory.

Which US Army Air Forces unit under Colonel Paul Tibbets was created to deliver the bombs?

It was activated in December 1944 at Wendover Field, Utah, and flew specially modified 'Silverplate' B-29 Superfortresses.

From which island in the Marianas did the atomic missions take off?

North Field on the island was about six hours' flying time from Japan.

Which city did Secretary of War Henry Stimson remove from the target list for its cultural significance?

Groves objected that it had military value; the story that Stimson had honeymooned there is a myth.

The 25 July 1945 order named four possible targets: Hiroshima, Nagasaki and which two other cities?

The Quebec Agreement of 1943 required British consent, which was obtained, before the weapons could be used.

Which test on 16 July 1945 proved the plutonium bomb design in the New Mexico desert?

Ten days later the Allies issued the Potsdam Declaration threatening 'prompt and utter destruction'.

What does 'mokusatsu', Suzuki's response to the Potsdam Declaration, mean?

He called the declaration a rehash of the Cairo Declaration and said Japan would fight to the end.

Roughly how many warning leaflets had the US dropped on Japanese cities before the atomic bombings?

The Interim Committee's scientific panel decided against a demonstration bomb and against a special leaflet warning for the atomic attack itself.

The B-29 Enola Gay was named after whom?

Colonel Paul Tibbets both named and flew the aircraft.

Why did weaponeer William Parsons wait until the Enola Gay was airborne to arm the Hiroshima bomb?

He loaded the four cordite bags into the gun breech in flight.

At what local time was the bomb released over Hiroshima on 6 August 1945?

It fell for 44.4 seconds from about 9,400 metres and detonated some 580 metres above the city.

What was the aiming point for the Hiroshima bomb, which it missed by about 240 metres?

Crosswind carried it to detonate directly over the Shima Surgical Clinic.

The Hiroshima bomb released energy equivalent to roughly how many kilotons of TNT?

That was four times the tonnage of conventional bombs that had destroyed Dresden.

Who was the Enola Gay's bombardier, who took control for the bomb run over Hiroshima?

Tibbets handed him control at 08:09; Kermit Beahan was the bombardier over Nagasaki three days later.

How many Japanese troops were killed on Hiroshima Castle's parade ground, 820 m from the hypocenter?

Most of the Second General Army headquarters was doing physical training there; the city's garrison was about 24,000 strong.

Which two other B-29s accompanied the Enola Gay to Hiroshima?

One carried instruments and the other cameras; Straight Flush had flown ahead as the weather plane.

How many American airmen were being held prisoner in Hiroshima about 400 metres from the hypocenter?

Most died instantly; two were reportedly executed by their captors and two badly injured were later killed.

What percentage of Hiroshima's buildings did Japanese officials determine had been destroyed?

US surveys estimated 12 square kilometres of the city were destroyed; another 6–7 per cent of buildings were damaged.

Which aircraft dropped the Fat Man bomb on Nagasaki?

It was flown by Major Charles Sweeney's crew, and early press reports confused it with The Great Artiste.

Which city was the primary target on 9 August, escaping when it was obscured by cloud and smoke?

Smoke was drifting from a firebombing raid on nearby Yahata the day before; Nagasaki was the secondary target.

What fault left the Nagasaki aircraft unable to use 640 gallons in a reserve tank on 9 August?

The fuel still had to be carried as dead weight, and after the delays the plane could barely reach Okinawa.

Why was the second bombing moved forward from 11 August to 9 August?

Responsibility for the timing had been delegated to Tibbets.

How much plutonium was in the core of the Fat Man bomb?

The Hiroshima bomb by contrast carried about 64 kg of uranium-235.

At what time did the Nagasaki bomb explode?

It burst about 503 metres up, above a tennis court, nearly 3 km from the planned hypocenter.

What was the yield of the Fat Man bomb dropped on Nagasaki?

Though more powerful than the Hiroshima bomb, its effects were confined by hillsides to the narrow Urakami Valley.

The Great Artiste's instruments over Nagasaki carried an unsigned letter to which Japanese physicist?

He had studied at Berkeley with three of the bomb's scientists, who urged him to tell the public about the weapon's danger.

Where did the Nagasaki bomber land after the mission, arriving unannounced with fuel for one approach?

Sweeney could not raise the control tower and had to fire flares to clear the runway.

Of 7,500 employees inside the Mitsubishi Munitions plant at Nagasaki, how many were killed?

The valley setting concentrated the blast; the radius of total destruction was about 1.6 km.

Worshippers filled Nagasaki's Urakami Cathedral when the bomb fell, preparing for which feast?

The cathedral near the hypocenter was completely destroyed; its belfry survives as a memorial.

Within two to four months, roughly how many people had died in Hiroshima?

Nagasaki's toll was 60,000 to 80,000; about half of all deaths came on the first day and some 90 per cent of the dead were civilians.

How many days after the Nagasaki bombing did Japan announce its surrender?

The Soviet Union had declared war and invaded Manchuria the same day as Nagasaki; the instrument of surrender was signed on 2 September.

How did Emperor Hirohito describe the new weapon in his surrender broadcast?

His later rescript to soldiers and sailors did not mention the bombs at all, citing instead the Soviet declaration of war.

What does the Japanese word 'hibakusha' mean?

The Japanese government has recognised about 650,000 people as hibakusha; many faced discrimination in marriage and work.

Why was double-bombing survivor Tsutomu Yamaguchi in Hiroshima on 6 August?

He returned home to Nagasaki in time for the second bomb; at least 160 people are known to have been affected by both.

Sadako Sasaki, who died of leukaemia in 1955 aged 12, is remembered for folding what?

Her father told her the legend that folding a thousand cranes grants a wish; a statue of her holding a golden crane stands in Hiroshima's Peace Memorial Park.

What was the Genbaku Dome, now the Hiroshima Peace Memorial, before the bombing?

Designed by Czech architect Jan Letzel, its skeleton survived almost directly beneath the blast.

Which two countries objected when the Genbaku Dome was made a UNESCO World Heritage Site in 1996?

They argued that other Asian nations had suffered greater losses and that a focus on Japan lacked historical perspective.

Where has the aircraft that bombed Nagasaki been on permanent display since 1961?

It stands next to a replica of the Fat Man bomb; the restored Enola Gay is at the Smithsonian's Udvar-Hazy Center.

The exhibition of the Enola Gay's forward fuselage in 1995 marked what, amid controversy?

After years parked outdoors and decades in storage, the fully restored bomber went on show at the Udvar-Hazy Center in 2003.

Which heavy cruiser carried the Hiroshima bomb's components from California to the Marianas in July 1945?

The pre-assemblies arrived on 26 July; the cruiser was torpedoed and sunk days later.

The Silverplate cover story claimed a Pullman car was being modified for which two leaders' tour?

'Thin Man' was Roosevelt and 'Fat Man' Churchill in the cover story, hence the bomb names.

Roughly how many Koreans, many of them forced labourers, were killed at Hiroshima?

A further 1,500–2,000 died at Nagasaki; Japan had brought as many as 670,000 Korean conscripts to work in the country.

Which storm struck Hiroshima on 17 September 1945, destroying more than half its bridges?

The city's population had fallen to 83,000 soon after the bombing but rose to 146,000 by February 1946.

Which Australian journalist's dispatch 'The Atomic Plague' ran in the Daily Express on 5 September 1945?

He reached Hiroshima alone by train on 2 September, defying a travel ban on Western correspondents.

John Hersey's book Hiroshima, first published in The New Yorker, follows how many survivors?

The English text reportedly reached Tokyo by January 1947 and a Japanese translation appeared in 1949.

Roughly how many people did the Manhattan Project employ at its peak?

Work took place at dozens of sites and cost more than $2 billion.

Which physicist's June 1945 report urged a demonstration of the bomb rather than direct use on a city?

The Scientific Advisory Panel rejected it, saying no technical demonstration was likely to end the war.

Which field marshal's Second General Army headquarters, commanding southern Japan's defence, was in Hiroshima?

Only slightly wounded, Hata took over the city's administration after the mayor was killed.