The year 1923 in science and technology involved some significant events, listed below.
Aeronautics
January 17 (or 9) – First stable flight of the first rotorcraft, Juan de la Cierva's Cierva C.4 autogyro, in Spain.
Astronomy and space science
June – Hermann Oberth publishes Die Rakete zu den Planetenräumen ("By Rocket into Planetary Space"). 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" ("On the 'language' of bees: an examination of animal psychology").
Chemistry
Dirk Coster and George de Hevesy publish their discovery of the transition metal element hafnium (72Hf) in zirconium ore, working in Copenhagen (Latin: Hafnia). 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 (in the United States) 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 diphtheria vaccine by Gaston Ramon, Emil von Behring and Kitasato Shibasaburō.
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 Banting and John Macleod
Copley Medal: Horace Lamb
Wollaston Medal for Geology: William Whitaker
Births
January 1 – Daniel Gorenstein (died 1992), American mathematician. February 13 – Chuck Yeager (died 2020), American pilot. February 14 – Doris Calloway, née Howes (died 2001), American nutritionist. February 20 – Helen Murray Free (died 2021), American medical chemist. March 4 – Patrick Moore (died 2012), English astronomer. March 9 – Walter Kohn (died 2016), Viennese-born physicist. March 10 – Val Logsdon Fitch (died 2015), American nuclear physicist, recipient of the Nobel Prize in Physics. April 1 – Brigitte Askonas (died 2013), Viennese-born British immunologist. April 2 – G. Spencer-Brown (died 2016), English mathematician. April 16 – Stewart Adams (died 2019), English pharmaceutical chemist. April 21 – Albert (Ab) C. Perdeck (died 2009), Dutch ornithologist. April 23 – Walter Pitts (died 1969), American logician and cognitive psychologist. July 5 – Ivo Pitanguy (died 2016), Brazilian plastic surgeon. July 12 – René Favaloro (died 2000), Argentine cardiac surgeon. July 23 – Ulf Grenander (died 2016), Swedish-born mathematician. July 28 – Xia Peisu (died 2014), Chinese computer scientist. July 31 – Stephanie Kwolek (died 2014), American polymer chemist. August 19 – Edgar F. Codd (died 2003), English-born computer scientist. September 9 – Daniel Carleton Gajdusek (died 2008), American virologist. September 13 – Miroslav Holub (died 1998), Czech immunologist and poet. September 26 – John Ertle Oliver (died 2011), American geophysicist. October 29 – Carl Djerassi (died 2015), Viennese-born chemist. November 8 – Jack Kilby (died 2005), American electrical engineer, recipient of the Nobel Prize in Physics. November 18 – Alan Shepard (died 1998), American astronaut. December 13 – Philip Warren Anderson (died 2020), American physicist, recipient of the Nobel Prize in Physics. December 15 – Freeman Dyson (died 2020), English-born theoretical physicist.