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ScienceMedicine

Radioactivity

Uranium emits something by itself, and the atom turns out not to be permanent.

When
Duration
6 years
Known to
± 1 year
Era
Industrial, Holocene

Becquerel finds in 1896 that uranium salts fog a photographic plate in the dark. Marie and Pierre Curie isolate polonium and radium, and Marie coins radioactivity, showing it is a property of atoms themselves rather than a chemical reaction — which means atoms change into other atoms. She is the first woman to win a Nobel Prize and the only person to win in two sciences. She died of aplastic anaemia from the exposure.

Just before

Just after