Today marks the 69th anniversary of the dropping of the first Atomic Bomb, the 5,000kg (roughly 11,000lbs) 'Little Boy' bomb. It contained about 64kg (140lbs) of Uranium and detonated about 600 metres (1800 feet) above the centre of the city. Estimates vary, but about 80,000 people died in the initial flash, and a further 20,000 of radiation and injuries in the ensuing three years. Since then about 1,900 people have died of ailments that may be related to the effects of radiation. Today, Hiroshima is a thriving city, completely rebuilt on the original site (the city dates back to the 14th Century) and is deemed to be free of radiation.
At the time the bomb was dropped, the city had a population of about 420,000 people and almost all of them suffered some form of injury or exposure to radiation. Post war studies showed, however, that the majority recovered fairly rapidly with treatment. The rebuilt city is now home to around 1.3 million people, with the total for the metropolitan area being around 2.2 million. There are a number of monuments to the bombing, among them the iconic Commercial Museum building shell near the city centre. This is the building seen in so many post bomb photos - the only standing structure in a sea of debris.
The contamination of the area was fairly low, largely because, being an 'airburst' most of the contaminants were carried into the stratosphere by the thermal column and mushroom cloud. Only about 2kg of the Uranium actually 'reacted' in fission, the rest being 'vapourised' in the process. It is a little mentioned fact that many of the survivors lived to great age, despite their experience and exposure. That said, theirs is an experience no one should have to undergo again.
As we mark this anniversary, let us pray for peace in the world.