It was August 13, 1945, and the ‘demon core’ was poised, waiting to be unleashed onto a stunned Japan still reeling in fresh chaos from the deadliest attacks anyone had ever seen.
These were the first and only nuclear bombs ever used in warfare, claiming as many as 200,000 lives – and if things had turned out a little differently, a third deadly strike would have followed in their hellish wake.
But history had other plans.
After Nagasaki proved Hiroshima was no fluke, Japan promptly surrendered on August 15, with Japanese radio broadcasting a recorded speech of Emperor Hirohito conceding to the Allies’ demands.
As it turns out, this was the first time the Japanese public at large had ever heard one of their emperors’ voices, but for scientists at the Los Alamos Laboratory in New Mexico – aka Project Y – the event had a more pressing significance.
It meant the functional heart of the third atom bomb they’d been working on – a 6.2-kilogram (13.7 lb) sphere of refined plutonium and gallium – wouldn’t be needed for the war effort after all.
If the conflict had still been raging, as it had for almost five straight years, this plutonium core would have been fitted into a second Fat Man assembly and detonated above another unsuspecting Japanese city just four days later.
The first accident happened less than a week after Japan’s surrender, and only two days after the date of the demon core’s cancelled bombing run.
That mission may have never launched, but the demon core, stranded at Los Alamos, still found an opportunity to kill.
The Los Alamos scientists knew well the risks of what they were doing when they conducted criticality experiments with it – a means of measuring the threshold at which the plutonium would become supercritical, the point where a nuclear chain reaction would unleash a blast of deadly radiation.
The trick performed by scientists in the Manhattan Project – of which the Los Alamos Lab was a part – was finding how just how far you could go before that dangerous reaction was triggered.
They even had an informal nickname for the high-risk experiments, one which hinted at the perils of what they did. They called it “tickling the dragon’s tail”, knowing that if they had the misfortune to rouse the angry beast, they would be burned.
And that’s exactly what happened to Los Alamos physicist Harry Daghlian.