Dr. Takashi Nagai: "If the atom explodes, what happens?"

Dr. Takashi Nagai, a radiologist transformed into peace witness after he and his family experienced the atomic bombing of Nagasaki, described the radical destructive force of uranium weapons in The Bells of Nagasaki:

"If the atom explodes, what happens?

...Four topics came to my mind for consideration: the enormous power of the atom, the elementary particles, the heat, the electromagnetic waves. Let me say a word about each of these.

First, the enormous power.

By enormous power, I mean the force that exists in the atom from the very moment of its creation, especially the force in the atomic nucleus. This is the force which maintains the form of the atom and is the source of tis activity. It is tremendous energy compared with the volume of the atom, and is the motive power behind the changes and movements of everything in the universe. Some scientists even hold that the gigantic quantity of energy emanating constantly, day and night, from the sun is nothing other than atomic energy from the constant explosion of the sun's atoms. If this is true, we could call the atom bomb a man-made, or artificial, sun.

When this enormous atomic force is released, it immediately and simulataneously exerts pressure on everything within a certain radius. The phenomenon, however, probably differs according to whether the explosion takes place in a vacuum, on earth, or in water.

In Nagasaki, the explosion took place in the air. The energy emitted pushed the molecules of air in all directions, and a tremendously powerful outward wind pressure spread over the surrounding area. In this way a vacuum was created at the center. And after the great wind pressure came negative pressure.

Since the explosion took place over Urakami which lies in a valley, the spherical blasts of wind collided with the walls of the valley, creating a tumultuous situation. To put it briefly: the principal pressure came frist to the ground, pushing down, crushing, breaking in pieces and blowing asunder everything that was there. There then followed the negative pressure which pulled everything in the opposite direction and sucked things up. Light rubble and debris were carried up in the sky forming a black cloud of dust. After that, complex wind pressures mingled with one another and raged for some time. It is not surprising, then, that people found themselves torn this way and that, without knowing where they were being pulled. The velocity of this atomic pressure was more or less the same as that of sound waves...

My next consideration was elementary particles.

The elements that fly about as initial particles are atomic constitutive particles such as neutrons, protons, alpha particicles, negative electrons, new atoms created by the fission of the atomic nucleus and original atoms that did not split...

Since enormous changes like this take place in an instant, great heat is naturally generated. All objects close to the enter of the explosion were burned. For example, the signpost at the entrance to the pharmaceutical department building still stands with the side facing the center of the explosion burned black. Black objects, which attract heat, were particularly badly burned. Let me give some examples of this.

The iris region of Inoue's eyes was pierced. The surface of black tiles became foamy. Some patients skin was badly burned only on those parts of the body covered by black clothing. And black parts of stones were most affected...

As a result of the sudden change in position of the electrified particles within the atom, there are distortions in the electric and magnetic fields, and these are radiated as electromagnetic waves. If we place them in order, beginning with the shortest wavelength, they are: gamma rays, X-rays, ultraviolet rays, visible light, infrared rays. There may exist electric waves with still longer wavelengths. The velocity of each of them is amazing: 299,790 kilometers per second. The moment they struck the eyes with a flash—that was the moment of the atomic explosion. Instantly terrible gamma rays pierced human bodies, and infrared rays badly burned the exposed parts.