X the Unknown
You probably recognize this picture as an X-ray image of a human hand. The hand has a big ring on the ring finger. This particular X-ray is the first X-ray image of a human body part ever made. It was taken by the man who discovered X-rays. The hand was his wife’s.
Why It Matters
- Some of the most important discoveries in the history of science have been made by chance or by accident.
- The discovery of X-rays by German physicist Wilhelm Roentgen in 1895 is a good example. Roentgen wasn’t looking for X-rays when he made the discovery. But Roentgen soon realized he had discovered a new type of rays. He named them X-rays, for X the unknown, because he didn’t know what they were.
- Almost immediately, the medical use of X-rays was appreciated. X-rays would eventually revolutionize medicine. They would also lead to some amazing discoveries in science, from black holes in outer space to the shape of DNA.
- You can watch a re-enactment of Roentgen’s discovery of X-rays in this video: http://www.youtube.com/watch?v=-OlOCxv1chM
Show What You Know
With the links below, learn more about X-rays and Roentgen’s discovery of them. Then answer the following questions.
- How did Roentgen accidentally discover X-rays?
- Shortly after Roentgen discovered X-rays, they were being used in medicine. How are X-rays used in medicine today?
- Explain how an X-ray image of bones, like the image above of Mrs. Roentgen’s hand, is made.
- X-ray machines generate X-rays in medicine. What are some natural sources of X-rays?
- How do scientists use X-rays? Identify an important discovery that was made using X-rays.
- Describe a practical use of X-rays outside of medicine or science.