Entry
The discovery of radioactivity — The announcement, in 1896, of a radiation proper to uranium salts
Investigating whether the fluorescence of uranium salts depended on the sun, Becquerel left a photographic plate in a drawer with a salt: it was fogged all the same. He concluded that the substance emits its own radiation, which was called hyperphosphorescence, and announced it to the Académie. The word radioactivity came two years later, from the Curies. (Editorial synthesis)
The discovery of radioactivity took place on 2 March 1896. (source: Larousse)
The discovery of radioactivity ended in invisible rays emitted by uranium. (source: Encyclopædia Britannica)
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