Discovery of X-rays

The discovery of x-rays is a fascinating story. It’s a moment that had a sudden and profound impact, but it took place quietly, in secret and by accident, in the laboratory of one inquisitive scientist. It’s a story about a naturally curious person who was paying attention to the right things at the right time. And like any good story about curiosity, it begins with an experiment.

On November 8, 1895, physicist Wilhelm Röntgen was testing the effects of sending electrical currents through glass vacuum-filled bulbs called cathode ray tubes. During one of his tests, Röntgen noticed that a screen on the other side of his lab began to glow whenever he sent electricity through the tube, even when the tube was fully covered with an opaque piece of cardboard.

Röntgen’s theory was that the tube was emitting an unknown kind of ray. He tried blocking the ray with different materials, but it seemed to pass through solid matter untouched. Then, by accident, he moved his hand through its path, and the shadows of his own bones were projected onto the screen. 

For seven weeks, he worked in secret. He x-rayed his wife’s hand, wearing her wedding ring. When his wife saw the first-ever radiographic image, she said, “I have seen my death!” 

In December of 1895, he published his findings. Röntgen gave his discovery the temporary name “X-ray,” for the mathematical term for an unknown quantity (“x”). Within weeks, the first clinical x-rays were taking place all over the world. Röntgen never patented his discovery, believing it should be freely available. In 1901, Röntgen received the first Nobel Prize in Physics. 

The x-ray gave us a new way of observing the world and ourselves. We could see right down to our bones, and even now, more than a century later, those eerie black and white images are still strange and powerful.