Harold Agnew carrying the plutonium core of the Nagasaki Fat Man bomb, 1945

Harold Agnew carrying the plutonium core of the Nagasaki Fat Man bomb, 1945

Man poses for a quick picture while innocuously carrying what could be a lunch box. It is the Physicist Harold Agnew and he is holding the plutonium core of the Nagasaki “Fat Man" atomic bomb.

There is something unsettling, perhaps even scary, about him having such a calm, relaxed and pleasant demeanor while casually holding something whose imminent detonation would be responsible for tens of thousands of deaths.

A somewhat odd photo and not terribly exciting unless you are aware of the details. Harold Agnew’s smile sort of disconnects the viewer from the reality of the situation. That box is the direct cause of the deaths of approximately 70,000 people. That little box will change the course of history, and he’s holding it like it’s his lunch.

The oddest thing here is that a whole group of scientists had photos of themselves posing with the plutonium core. They were proud of their invention, and the fact that they were making history. For a whole lot of reasons, they had no second thoughts about what they were planning to do.

Harold Agnew saw the completion of the atomic bomb from start to finish. As a member of Enrico Fermi’s research team at the University of Chicago in 1942, Agnew witnessed the first sustained nuclear chain reaction, Chicago Pile-1. He worked in the Experimental Physics Division at Los Alamos from 1943 to 1945.

While the Trinity test was being conducted, Agnew was already on his way to Tinian Island in the Pacific as part of Project Alberta, the group responsible for the final bomb assembly.

He flew as a scientific observer on a B-29 bomber for the Hiroshima bombing mission, measuring the size of the shock wave to determine the bomb’s power. He also filmed the explosion with a movie camera.

The plutonium core (the box) in the Fat Man weighed 6.2 kg or about 14 lb, the pit is 9 cm (4 inches) across. And only about one-fifth of it, a bit over 1 kg (2 pounds) undergoes a fission reaction. And only a gram (1/30th of an ounce) of that gets converted into explosive energy equal to 21,000 tons of TNT.

Fat Man was the codename for the type of atomic bomb that was detonated over the Japanese city of Nagasaki by the United States on 9 August 1945. It was the second of the only two nuclear weapons ever used in warfare, the first being Little Boy, and its detonation marked the third-ever man-made nuclear explosion in history.

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