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Uranic Rays



The first clue of a new phenomenon

Wilhelm Konrad Roentgen
Wilhelm Konrad Roentgen, a German physicist, announced the discovery of X-rays on the 28th of December 1895. The X-ray scan of his wife’s hand was published in newspapers all around the world and caused an instant sensation. His work was rewarded with a Nobel Prize for Physics in 1901.
Musée Curie
On the 28th of December 1895, Wilhelm Conrad Roentgen announced the discovery of X-rays. The scan of his wife’s hand was published in newspapers all around the world and caused an instant sensation.

As of mid-January 1896, doctors and physicists in all Western countries were using the X-ray apparatus described by Roentgen to perform scans of their own. The Parisian physicist Oudin and the doctor B. Barthelemy made the first French X-ray scan, the results of which were presented to the Academie des Sciences by Henri Poincare on the 20th of January. At the presentation, Poincare suggested to Henri Becquerel that he investigate whether a relationship existed between phosphorescence and X-ray emission.

Henri Becquerel belonged to what could almost be called a dynasty of curious thinkers and scientists that were working at the time. He worked in a laboratory at the Natural History Museum in Paris and devoted much of his time to exploring the relationship between phosphorescence and fluorescence.

Becquerel then decided to see whether or not X-ray emission was linked to phosphorescence. On an overcast day in March 1896, unable to expose a phosphorescent uranium salt to the sun, he placed the uranium on top of a fresh sheet of photographic paper at the back of a drawer. Some days later he discovered that the salt had spontaneously emitted a penetrative ray capable of leaving an impression on the photographic plate.

Henri Becquerel in his laboratory.
Henri Becquerel (1852-1908), a graduate of the Polytechnic School, belonged to what could almost be called a dynasty of curious thinkers and scientists that were working at the time. He worked in a laboratory at the Natural History Museum in Paris and devoted much of his time to exploring the relationship between phosphorescence and fluorescence.
ACJC
Becquerel quickly established that a variety of uranium salts, whether phosphorescent or not, have the same property; proving that the radiation is an intrinsic characteristic of uranium.

He referred to the emitted rays as ‘uranic rays’, and was able to show that they could electrify the air. As the intensity did not diminish over time, Becquerel started asking himself: Where does uranium get the energy that it emits so consistently?

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