1938–1945 CE · experimental fission, interpretation, chain reaction and atomic war · Europe · Science
Hahn and Strassmann’s 1938 experiments produced evidence of uranium fission; Meitner and Frisch supplied the physical interpretation and name. Chain-reaction research then led rapidly to a reactor and the Manhattan Project.
Atlas dossier · World WarsFree device narration · synchronized English captions · transcript available
Why it matters
Hahn and Strassmann reported barium among the products of neutron-bombarded uranium in December 1938. Meitner and Frisch explained the result as nuclear fission and estimated the released energy. Naming both stages corrects a prize-centred story without pretending that a wider laboratory network can be reduced to four names.
IAEA: Lise Meitner and the discovery of nuclear fission ↗Chain-reaction research led to the first controlled reactor and then to weapons produced by the Manhattan Project. The atomic bombings of Hiroshima and Nagasaki killed civilians immediately and through later injury and radiation. The endpoint connects laboratory history to warfare without claiming that reactors, nuclear medicine, arms racing or disarmament ended in 1945.
Academic research on fission and the nuclear age ↗A visual presentation accompanying this entry. Read each image’s attribution to distinguish archival records, later depictions and reconstructions.
Enlarge and examine the pictureRights-cleared archival or official image · Public domain
Lise Meitner NatGeo.jpg — Harris & Ewing; Public domain; via Wikimedia Commons
Source and reuse terms ↗Interpretation note
This dossier distinguishes the event’s basic chronology from later arguments about meaning, responsibility and legacy. When comparing religious, national, Indigenous or scholarly interpretations, consult the primary and institutional sources above alongside peer-reviewed historical work.
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