The First Human X-Ray
Wilhelm Röntgen was a German physicist who discovered and experimented with x-rays in the late 18th century. He called them x-rays because their properties were a mystery—the "x" stood for "unknown."
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Key Facts In This Video
X-rays have waves that are a longer than gamma rays, but shorter than visible light. (0:33)
Early x-rays released far more radiation than current technology, causing skin ailments, burns, and death. (1:25)
Today's x-rays release small, typically negligible amounts of radiation. (2:25)