Eighty years ago today, an American B-29 bomber dropped an atomic bomb on the Japanese city of Hiroshima.
It was the dawn of the atomic age, but the birth of the bomb can be traced beyond the deserts of New Mexico to Britain, five years earlier.
A copy of a hand-typed document, now in the Bodleian library in Oxford, is the first description of an atom bomb small enough to use as a weapon.
The Frisch-Peierls Memorandum was written by two nuclear physicists at the University of Birmingham in 1940.
Otto Frisch and Rudolf Peierls don’t feature in the film Oppenheimer, but their paper is credited with jump-starting the Manhattan Project that ultimately built the bomb.
Both Jewish scientists who had both fled Nazi Germany, they built on the latest understanding of uranium fission and nuclear chain reactions, to propose a bomb made from enriched uranium that was compact enough to be carried by an aircraft.
The document, so secret at the time only one copy was made, makes for chilling reading.
Not only does it detail how to build a bomb, but foretells the previously unimaginable power of its blast.
“Such an explosion would destroy life in a wide area,” they wrote.
“The size of this area is difficult to estimate, but it will probably cover the centre of a big city.”
Radioactive fallout would be inevitable “and even for days after the explosion any person entering the affected area will be killed”.
Both lethal properties of the bombs that would subsequently fall on Hiroshima and Nagasaki, killing around 100,000 instantly and more than 100,000 others in the years that followed – most of them civilians.
Read more:
Hiroshima survivor’s stark warning
The ‘destroyer of worlds’ who built the atomic bomb
