16 Facts You Didn't Know About the Hiroshima Bombing

By James O Malley on at

Today marks the 70th anniversary of the US bombing of Hiroshima, the first ever use of nuclear weapons in combat. The event was extraordinary for a number of reasons, as it marked the beginning of the nuclear age, the onset of the Cold War and the fact that humankind had so thoroughly mastered nature that it could now wipe out every living thing on the planet in the blink of an eye, if it wanted to.

To commemorate, here’s 16 snippets of trivia about the significant, but ominous day.

1.) America warned Japanese citizens about the nuclear attacks

In the days leading up to the Hiroshima and Nagasaki bombings the US Air Force dropped not bombs but leaflets, warning Japanese citizens that they should evacuate the cities listed if they want to save their lives:

“These cities contain military installations and workshops or factories which produce military goods. We are determined to destroy all of the tools of the military clique which they are using to prolong this useless war. But, unfortunately, bombs have no eyes. So, in accordance with America’s humanitarian policies, the American Air Force, which does not wish to injure innocent people, now gives you warning to evacuate the cities named and save your lives. America is not fighting the Japanese people but is fighting the military clique which has enslaved the Japanese people.”

The message was also broadcast on radio every 15 minutes on an American controlled station. After the Hiroshima attack, more leaflets were dropped explaining that it was all caused by just one bomb - and that Nagasaki residents should heed its warning. [Damn Interesting] [Pic]

Related: What if the Hiroshima Nuclear Bomb Was Dropped on Present Day London?

2.) The Hiroshima and Nagasaki Bombs were actually very different

The two bombs that were dropped on Japan just days apart were actually very different in terms of design. The Hiroshima bomb, nicknamed Little Boy, was based on enriched Uranium-235 whereas Nagasaki’s Fat Man was instead based on 8kg of Plutonium-239 - which was refined through a more complex process. The US was able to use the bombings to test which was more effective. [Difference Between] [Pic]

3.) Little Boy used almost all the Uranium in existence

In order to make the bomb that hit Hiroshima, the US used 141 pounds of Uranium, basically all of the processed Uranium that was then in existence. What’s interesting though is that according to Command and Control by Eric Schlosser, when the bomb exploded most of it was blown apart before the bomb reached the “supercritical” phase. In the end, the huge explosion was caused by just 0.7g of Uranium. As Schlosser notes, that’s material that weighs less than a dollar bill that killed 80,000 people. [Pic]

4.) The bomb was only finally assembled in the air

Making the flight must have been nerve-wracking enough for the air crew, but it turns out that they had to do the final assembly on the bomb and arm it whilst in flight. Again according to Schlosser’s book, Captain Parsons who was in charge of the mission decided that if the plane had crashed on take-off, or if something had gone wrong, he didn’t want the explosion to wipe out the US base and thousands of US soldiers on Tinian, the Pacific island where the Enola Gay was to take off from.

So instead it was up to the air crew to sort things out whilst the bomb hung from a hook in a moving plane that was flying over enemy territory. [Pic]

5.) If the Enola Gay had been shot down, the bomb would have been effectively a dirty bomb.

The Little Boy bomb on the plane, like many bombs at the time, had to be armed during the flight, using four safety switches. If, for whatever reason, the plane had been shot down or it had otherwise exploded accidentally, the effect would most likely have been akin to what in the 21st century is known as a “dirty bomb” - a crude blast of radiation rather than a massive explosion.

6.) It wasn’t actually the bombing which ended WWII

It is commonly thought that it was the bombings of Hiroshima and Nagasaki that brought about a swift end to World War II. Surely it is unsurprising that upon seeing the devastating power of these super-weapons the Japanese government quickly surrendered?

However, a growing body of historians now believe that the bombing is a bit of a red herring, and Japanese surrender can actually be attributed by the entry of the Soviet Union into the war. The Soviets, who had previously been occupied (both literally and figuratively) fighting Germany only declared war on Japan on the 9th August 1945, just three weeks before Japan officially capitulated.

According to historian Tsuyoshi Hasegawa until the Soviets entered the war, the Japanese government had been plotting to end the combat, but on more favourable terms: Hoping to use the Soviet Union to persuade the US to accept a less unconditional surrender. Unfortunately for Japan, when Stalin declared war, then this meant that they were screwed, so they just gave up. [Boston.com]

7.) Some US Airmen were caught in the bombing

Obviously whatever the politics, Hiroshima was a human tragedy too as so many tens of thousands were killed. But what you might not know is that amongst the victims were some US airmen.

Three planes that were flying missions over Hiroshima were shot down in the days before the bombing, with the crew of Lonesome Lady all managing to bail out and survive the crash… before being quickly captured and imprisoned in a base in Hiroshima.

Apparently the instructions given to captured airmen was to tell captors the truth, as the US assumed that Japanese already knew what was planned, and telling the truth would minimise torture. But despite Captain Tom Cartwright telling his captors what they asked, he was shipped off to Tokyo for a more ‘robust’ interrogation. This turned out to be a very lucky move, as when the bomb hit Hiroshima he wasn’t in the blast radius, unlike his unlucky colleagues. [SymonSez]

8.) Tsutomu Yamaguchi might be the unluckiest (or luckiest) man in history

Tsutomu Yamaguchi worked for Mitsubishi Heavy Industries in Nagasaki and on the 6th August 1945 he was visiting the city of Hiroshima on business. He was caught in the blast but managed to survive, and despite his wounds was able to travel back to Nagasaki the next day. Unfortunately for him on August 9th the Americans then dropped Fat Man on to the city he had just arrived in.

Astonishingly, despite being hit by two nukes he survived this too, and in fact only died in 2010, at the ripe old age of 93. He’s the only person recognised by the Japanese government as having survived both explosions. We just can’t work out if this makes him unlucky, or very lucky indeed.

9.) The co-pilot of the Enola Gay met Hiroshima victims on This Is Your Life

In 1955, ten years after the bombing, several Japanese victims were flown to America to receive plastic surgery. US television thought it would be a good opportunity to reunite victims of the Hiroshima bombing with the co-pilot of the plane which dropped the bomb. Footage of the extraordinary meeting was featured in a US documentary, and it appears that the meeting was every bit as awkward as you might expect.

10.) Colour Footage of the Bombing Actually Exists

When we think of the Hiroshima bomb it conjures up grainy black and white images - both of the explosion, and the aftermath. But it turns out some surprisingly high quality colour footage exists, but it was only uncovered in 2011 after being hidden away by the US military. You can see some of it in the video above. It was shot in the weeks after the explosion, and even shows some of the damage done to people (so be warned, the video could be a bit distressing, but then you are reading a post about nuclear devastation).

11.) Thermal radiation had an unusual effect

Another disturbing fact from Command and Control. When the bomb in Hiroshima went off, the thermal radiation caused burns on people who were not killed by the explosion. But the severity of the burns depended on the clothes they were wearing, with white clothes reflecting radiation and black absorbing it. This meant that if people were wearing striped clothes when the bomb hit, the burns pattern matched their outfit. [Pic]

12.) A bank vault survived the explosion

Whilst much of Hiroshima was wiped out (as you can see in the video above), one thing that did survive intact was the vault at the Teikoku Bank. So impressed was the manager that five years after the manager wrote to the safe’s American manufacturer, The Mosler Safe Company, to thank them. As you might imagine, the safe company turned the incident into quite the promotional boast. [Letters of Note]

13.) An anime was produced about the bombing

The Japanese have long taken cartoons more seriously than the west, and in 1983 Barefoot Gen made for a harrowing story of the bomb told from a child’s point of view. Check out the clip to see a disturbing visualisation of the effects of the blast. It's accompanying manga is now considered one of the greatest graphic novels of all time.

14.) Hiroshima also inspired Godzilla

The first Godzilla film was released in Japan in 1954, less than ten years after the bombing. Whilst it may seem to us like a ludicrous monster, the creature was actually conceived as a metaphor for nuclear weapons. Thematically the nuclear metaphor has been present throughout Godzilla’s history, and was particularly played upon in last year’s reboot too.

15.) America also nuked Japan in 1954 (sort of)

In 1954 as the Cold War arms race was continuing America tested a new type of nuke, the hydrogen bomb, at Bikini Atoll on the 1st March. Unfortunately, the crew of the SS Lucky Dragon 5 were in the area and caught in the fall out. Within weeks the boat’s chief radioman, Aikichi Kuboyama, was dead. But other crew members lived relatively normal lives, but were sadly stigmatised due to Japanese paranoia over radiation following the earlier bombings. [Pic]

16.) A Hiroshima survivor won the Boston marathon

When Shigeki Tanaka was 13 years old he was living 20 miles from Hiroshima, seeing and hearing the bomb go off. Six years later he won the Boston marathon, completing the course in 2 hours 27 minutes and 45 seconds. The win was not just seen as a personal victory, but also helped restore Japanese pride and honour following the war. (1951, the year he won, was the first year that Japanese athletes were invited to participate, following the war). [Pic]