1935

Nobel Prize in Physics

James Chadwick

Three years after the fact, the committee caught up with Chadwick's neutron. It was, in retrospect, one of the more important particles available — electrically neutral, it could penetrate atomic nuclei without being deflected by their charge, making it the ideal tool for everything that came next in nuclear physics.

Nobel Prize in Chemistry

Frédéric Joliot · Irène Joliot-Curie

The prize went to the daughter of Marie Curie and her husband for the synthesis of new radioactive elements — the demonstration that radioactivity was not just a natural condition to observe but a property you could confer. It was an irony of the quietest kind that Irène's mother had died the previous year from exactly the kind of exposure this work required.

Nobel Prize in Physiology or Medicine

Hans Spemann

Spemann transplanted tiny pieces of embryonic tissue between salamander eggs and watched the transplants instruct the surrounding cells to reorganise themselves into structures they would otherwise never have formed. He called the responsible tissue the organiser, which turned out to be modest — it is, effectively, the thing that tells an embryo which end is which.

Nobel Peace Prize

Carl von Ossietzky

Ossietzky was a German journalist who had exposed secret German rearmament in violation of the Versailles Treaty, for which the Weimar government imprisoned him briefly and the Nazi government imprisoned him at length. The peace prize was awarded to him while he was in a concentration camp; the empty chair at the Oslo ceremony was among the more eloquent images of the decade.

Discovery of the muon

Carl David Anderson · Seth Neddermeyer

Anderson and Neddermeyer were examining cosmic rays when they found a particle that curved in a magnetic field with a radius suggesting it was roughly 200 times heavier than an electron but far lighter than a proton. It fit no existing theory and fitted no known need, which prompted the physicist I.I. Rabi to ask, with justified exasperation, "Who ordered that?"

Szilard develops nuclear chain reaction concept

Leó Szilard

Szilard had conceived the idea of a nuclear chain reaction in 1933, while crossing a London street, and patented it the following year. By 1935 he was refining and worrying over it: if a neutron striking a nucleus released further neutrons, and those released more, the multiplication would be swift and the consequences very large. He was, with some justification, frightened by his own thought experiment.

First medical use of radioactive isotopes

Radioactive iodine was used therapeutically for thyroid disease — the first deliberate application of artificial radioactivity to medicine. The thyroid gland concentrates iodine naturally; a radioactive version concentrates in the same tissue and delivers its dose precisely where it is wanted, which is a more elegant weapon than most medicine could then offer.