1923 in science

Aeronautics

• Juan de la Cierva invents the autogyro, a rotary-winged aircraft with an unpowered rotor.

  Astronomy and space science

• June – Hermann Oberth publishes Die Rakete zu den Planetenräumen.
• October 21 – First official public showing of a planetarium projector, a Zeiss model at the Deutsches Museum in Munich.

  Biology

• Karl von Frisch publishes "Über die 'Sprache' der Bienen. Eine tierpsychologische Untersuchung".

  Chemistry

• Dirk Coster and George de Hevesy publish their discovery of the transition metal element hafnium in zirconium ore, working in Copenhagen.
• Niels Bohr and Dirk Coster, working in Copenhagen, produce a paper on X-ray spectroscopy and the periodic system of the elements.
• Gilbert N. Lewis and Merle Randall's textbook Thermodynamics and the Free Energy of Chemical Reactions is influential in the replacement of the concept of chemical affinity by free energy.

  Cryptography

• Enigma machine first produced commercially.

  Electronics

• Otto Julius Zobel of Bell Labs describes the type of signal processing filter sections based on the image impedance design principle which will become known as Zobel networks.
• December 29 – Vladimir K. Zworykin files his first patent for "television systems".

  Exploration

• Tanager Expedition.

  Medicine

• February – The Maudsley Hospital, established jointly by the London County Council and Henry Maudsley, admits its first psychiatric patients.
• First vaccine for Diphtheria

  Paleontology

• July 13 – An American Museum of Natural History expedition to Mongolia under Roy Chapman Andrews is the first in the world to discover fossil dinosaur eggs. Initially thought to belong to the ceratopsian Protoceratops, they are determined in 1995 actually to belong to the theropod Oviraptor. On August 11 Peter Kaisen recovers the first Velociraptor fossil known.

  Physics

• Arthur Eddington publishes the textbook The Mathematical Theory of Relativity in Cambridge.

  Technology

• Herbert Grove Dorsey invents the first practical fathometer.

  Awards

• Nobel Prizes
• * Physics: Robert Andrews Millikan
• * Chemistry: Fritz Pregl
• * Medicine: Frederick Grant Banting and John James Rickard Macleod
• Copley Medal: Horace Lamb
• Wollaston Medal for Geology: William Whitaker

  Births

• January 1 – Daniel Gorenstein, American mathematician.
• February 13 – Chuck Yeager, American pilot.
• February 14 – Doris Calloway, née Howes, American nutritionist.
• March 4 – Patrick Moore, English astronomer.
• March 9 – Walter Kohn, Viennese-born physicist.
• March 10 – Val Logsdon Fitch, American nuclear physicist, recipient of the Nobel Prize in Physics.
• April 1 – Brigitte Askonas, Viennese-born British immunologist.
• April 2 – G. Spencer-Brown, English mathematician.
• April 16 – Stewart Adams, English pharmaceutical chemist.
• April 21 – :nl:Albert C. Perdeck|Albert C. Perdeck, Dutch ornithologist.
• April 23 – Walter Pitts, American logician and cognitive psychologist.
• July 5 – Ivo Pitanguy, Brazilian plastic surgeon.
• July 12 – René Favaloro, Argentine cardiac surgeon.
• July 23 – Ulf Grenander, Swedish-born mathematician.
• July 28 – Xia Peisu, Chinese computer scientist.
• July 31 – Stephanie Kwolek, American polymer chemist.
• September 9 – Daniel Carleton Gajdusek, American virologist.
• September 13 – Miroslav Holub, Czech immunologist and poet.
• September 26 – John Ertle Oliver, American geophysicist.
• October 29 – Carl Djerassi, Viennese-born chemist.
• November 8 – Jack Kilby, American electrical engineer, recipient of the Nobel Prize in Physics.
• November 18 – Alan Shepard, American astronaut.
• December 13 – Philip Warren Anderson, American physicist, recipient of the Nobel Prize in Physics.
• December 15 – Freeman Dyson, English-born theoretical physicist.

  Deaths

• February 10 – Wilhelm Röntgen, physicist, discoverer of X-rays, Nobel laureate.
• February 24 – Edward Morley, chemist.
• March 8 – Johannes Diderik van der Waals, physicist.
• March 27 – James Dewar, chemist.
• July 16 – Sydney Mary Thompson, geologist and botanist.
• August 23 – Hertha Ayrton, electrical engineer.
• October 3 – Kadambini Ganguly, physician.
• December 2 – Henry Haversham Godwin-Austen, surveyor, geologist and naturalist.
• December 7 – Sir Frederick Treves, surgeon.
• December 27 – Gustave Eiffel, structural engineer.