Later, Austrian and German scientists showed that when uranium is struck
by neutrons, it splits into two nearly equal parts plus one or two extra
neutrons. Lisa Meitner, an Austrian physicist, was the first to point out
that if these fragments added up to less mass than the original uranium
nucleus, then Einstein's special relativity theory predicted that a large
amount of energy would be released. Enrico Fermi, an Italian working with
colleagues in the United States, showed that the extra neutrons trigger
more fissions and so create a sustained chain reaction in which a prodigious
amount of energy is given off.
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Nature of Science (grades 9-12): Historical Perspectives.
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