The year 1905 in

science Science is a systematic endeavor that Scientific method, builds and organizes knowledge in the form of Testability, testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earli ...

and

technology Technology is the application of knowledge to reach practical goals in a specifiable and reproducible way. The word ''technology'' may also mean the product of such an endeavor. The use of technology is widely prevalent in medicine, scie ...

involved some significant events, particularly in physics, listed below. Einstein patentoffice

Astronomy

* January 2 –

Charles Dillon Perrine Charles Dillon Perrine (July 28, 1867June 21, 1951) was an American astronomer at the Lick Observatory in California (1893-1909) who moved to Cordoba, Argentina to accept the position of Director of the Argentine National Observatory (1909-1936 ...

at Lick Observatory discovers Elara, one of

Jupiter's natural satellites There are 82 known moons of Jupiter, not counting a number of moonlets likely shed from the inner moons. All together, they form a satellite system which is called the Jovian system. The most massive of the moons are the four Galilean moons: ...

. * The

Dominion Observatory The Dominion Observatory was an astronomical observatory in Ottawa, Ontario that operated from 1902 to 1970. The Observatory was also an institution within the Canadian Federal Government. The observatory grew out of the Department of the Inter ...

opens in

Ottawa Ottawa (, ; Canadian French: ) is the capital city of Canada. It is located at the confluence of the Ottawa River and the Rideau River in the southern portion of the province of Ontario. Ottawa borders Gatineau, Quebec, and forms the core ...

. * Various astronomers discover the

minor planets According to the International Astronomical Union (IAU), a minor planet is an astronomical object in direct orbit around the Sun that is exclusively classified as neither a planet nor a comet. Before 2006, the IAU officially used the term ''minor ...

554 Peraga Peraga (minor planet designation: 554 Peraga) is a minor planet orbiting the Sun that was discovered by German astronomer Paul Götz on January 8, 1905, from Heidelberg. 13-cm radar observations of this asteroid from the Arecibo Observatory ...

through

583 Klotilde Klotilde (minor planet designation A formal minor-planet designation is, in its final form, a number–name combination given to a minor planet (asteroid, centaur, trans-Neptunian object and dwarf planet but not comet). Such designation always ...

(''see'' List of minor planets/501–600). * The

nova A nova (plural novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", which is Latin for "new") that slowly fades over weeks or months. Causes of the dramati ...

V604 Aquilae appears in the constellation

Aquila Aquila may refer to: Arts, entertainment, and media * ''Aquila'', a series of books by S.P. Somtow * ''Aquila'', a 1997 book by Andrew Norriss * ''Aquila'' (children's magazine), a UK-based children's magazine * ''Aquila'' (journal), an or ...

. * The Umov effect is noted by

Nikolay Umov Nikolay Alekseevich Umov (russian: Никола́й Алексе́евич У́мов; January 23, 1846 – January 15, 1915) was a Russian physicist and mathematician known for discovering the concept of Umov-Poynting vector and Umov effect. ...

Biology

* April 18 –

William Bateson William Bateson (8 August 1861 – 8 February 1926) was an English biologist who was the first person to use the term genetics to describe the study of heredity, and the chief populariser of the ideas of Gregor Mendel following their rediscover ...

coins the term "

genetics Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar worki ...

" in a letter to Adam Sedgwick. *

Reginald Punnett Reginald Crundall Punnett FRS (; 20 June 1875 – 3 January 1967) was a British geneticist who co-founded, with William Bateson, the '' Journal of Genetics'' in 1910. Punnett is probably best remembered today as the creator of the Punne ...

's ''Mendelism'' is published in Cambridge (U.K.), probably the first

popular science ''Popular Science'' (also known as ''PopSci'') is an American digital magazine carrying popular science content, which refers to articles for the general reader on science and technology subjects. ''Popular Science'' has won over 58 awards, incl ...

book on genetics. *

Frederick Blackman Frederick Frost Blackman FRS (25 July 1866 – 30 January 1947) was a British plant physiologist. Frederick Blackman was born in Lambeth, London to a doctor. He studied medicine at St. Bartholomew's Hospital, graduating MA. In the subsequent ye ...

proposes his law of limiting factors in relation to

photosynthesis Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored i ...

. *

Nettie Stevens Nettie Maria Stevens (July 7, 1861 – May 4, 1912) was an American geneticist who discovered sex chromosomes. In 1905, soon after the rediscovery of Mendel's paper on genetics in 1900, she observed that male mealworms produced two kinds of sp ...

and

Edmund Beecher Wilson Edmund Beecher Wilson (October 19, 1856 – March 3, 1939) was a pioneering American zoologist and geneticist. He wrote one of the most influential textbooks in modern biology, ''The Cell''. Career Wilson was born in Geneva, Illinois, the ...

independently describe the

XY sex-determination system The XY sex-determination system is a sex-determination system used to classify many mammals, including humans, some insects (''Drosophila''), some snakes, some fish ( guppies), and some plants ('' Ginkgo'' tree). In this system, the sex of an ...

. *

Stamen Grigorov Stamen Gigov Grigorov ( bg, Стамен Гигов Григоров; 27 October 1878 – 27 October 1945) was a prominent Bulgarian physician and microbiologist. He discovered the ''Lactobacillus bulgaricus'' bacillus, used in the making of yogur ...

identifies the

bacterium Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were a ...

Lactobacillus bulgaricus ''Lactobacillus delbrueckii'' subsp. ''bulgaricus'' (until 2014 known as ''Lactobacillus bulgaricus'') is one of over 200 published species in the ''Lactobacillus'' genome complex (LGC) and is the main bacterium used for the production of yogurt. ...

'', a major agent in the creation of

yogurt Yogurt (; , from tr, yoğurt, also spelled yoghurt, yogourt or yoghourt) is a food produced by bacterial fermentation of milk. The bacteria used to make yogurt are known as ''yogurt cultures''. Fermentation of sugars in the milk by these bact ...

. *

Maltese Maltese may refer to: * Someone or something of, from, or related to Malta * Maltese alphabet * Maltese cuisine * Maltese culture * Maltese language, the Semitic language spoken by Maltese people * Maltese people, people from Malta or of Malte ...

doctor and archaeologist

Themistocles Zammit Sir Themistocles "Temi" Zammit (or Żammit; 30 September 1864 – 2 November 1935) was a Maltese archaeologist and historian, professor of chemistry, medical doctor, researcher and writer. He served as Rector (1920–26) of the Royal Univer ...

identifies

unpasteurized Pasteurization or pasteurisation is a process of food preservation in which packaged and non-packaged foods (such as milk and fruit juices) are treated with mild heat, usually to less than , to eliminate pathogens and extend shelf life. The ...

milk as the major source of the pathogen causing

Brucellosis Brucellosis is a highly contagious zoonosis caused by ingestion of unpasteurized milk or undercooked meat from infected animals, or close contact with their secretions. It is also known as undulant fever, Malta fever, and Mediterranean fever. T ...

. * National Association of Audubon Societies for the Protection of Wild Birds and Animals established in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

Chemistry

Carl von Linde Carl Paul Gottfried von Linde (11 June 1842 – 16 November 1934) was a German scientist, engineer, and businessman. He discovered a refrigeration cycle and invented the first industrial-scale air separation and gas liquefaction processes, whi ...

obtains pure

liquid oxygen Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is the liquid form of molecular oxygen. It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an a ...

and

nitrogen Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seve ...

by cooling air. *

Alfred Einhorn Alfred Einhorn (27 February 1856 – 21 March 1917) was a German chemist most notable for first synthesizing procaine in 1905 which he patented under the name Novocain. Until that time the primary anesthetic in use was cocaine, however its und ...

synthesises the

local anesthetic A local anesthetic (LA) is a medication that causes absence of pain sensation. In the context of surgery, a local anesthetic creates an absence of pain in a specific location of the body without a loss of consciousness, as opposed to a general an ...

novocaine Procaine is a local anesthetic drug of the amino ester group. It is most commonly used in dental procedures to numb the area around a tooth and is also used to reduce the pain of intramuscular injection of penicillin. Owing to the ubiquity of ...

. * The first commercial use of the

Frank–Caro process The Frank–Caro process, also called cyanamide process, is the nitrogen fixation reaction of calcium carbide with nitrogen gas in a reactor vessel at about 1,000 °C. The reaction is exothermic and self-sustaining once the reaction tempe ...

for the

nitrogen fixation Nitrogen fixation is a chemical process by which molecular nitrogen (), with a strong triple covalent bond, in the air is converted into ammonia () or related nitrogenous compounds, typically in soil or aquatic systems but also in industry. At ...

reaction of

calcium carbide Calcium carbide, also known as calcium acetylide, is a chemical compound with the chemical formula of Ca C2. Its main use industrially is in the production of acetylene and calcium cyanamide. The pure material is colorless, while pieces of te ...

and atmospheric

to produce

calcium nitrate Calcium nitrate, also called ''Norgessalpeter'' (Norwegian salpeter), is an inorganic compound with the formula Ca(NO3)2(H2O)x. The anhydrous compound, which is rarely encountered, absorbs moisture from the air to give the tetrahydrate. Both anhy ...

as a

fertilizer A fertilizer (American English) or fertiliser (British English; see spelling differences) is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from ...

. *

Fritz Haber Fritz Haber (; 9 December 186829 January 1934) was a German chemist who received the Nobel Prize in Chemistry in 1918 for his invention of the Haber–Bosch process, a method used in industry to synthesize ammonia from nitrogen gas and hydroge ...

and

Carl Bosch Carl Bosch (; 27 August 1874 – 26 April 1940) was a German chemist and engineer and Nobel Laureate in Chemistry. He was a pioneer in the field of high-pressure industrial chemistry and founder of IG Farben, at one point the world's larges ...

develop the

Haber process The Haber process, also called the Haber–Bosch process, is an artificial nitrogen fixation process and is the main industrial procedure for the production of ammonia today. It is named after its inventors, the German chemists Fritz Haber and ...

for making

ammonia Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogeno ...

from its elements, a milestone in industrial chemistry with deep consequences in agriculture.

Mathematics

Pierre Fatou Pierre Joseph Louis Fatou (28 February 1878 – 9 August 1929) was a French mathematician and astronomer. He is known for major contributions to several branches of analysis. The Fatou lemma and the Fatou set are named after him. Biography P ...

defines the

Mandelbrot set The Mandelbrot set () is the set of complex numbers c for which the function f_c(z)=z^2+c does not diverge to infinity when iterated from z=0, i.e., for which the sequence f_c(0), f_c(f_c(0)), etc., remains bounded in absolute value. This ...

. *

Oswald Veblen Oswald Veblen (June 24, 1880 – August 10, 1960) was an American mathematician, geometer and topologist, whose work found application in atomic physics and the theory of relativity. He proved the Jordan curve theorem in 1905; while this was long ...

proves the

Jordan curve theorem In topology, the Jordan curve theorem asserts that every '' Jordan curve'' (a plane simple closed curve) divides the plane into an "interior" region bounded by the curve and an " exterior" region containing all of the nearby and far away exterio ...

. *

Martin Kutta Martin Wilhelm Kutta (; 3 November 1867 – 25 December 1944) was a German mathematician. Kutta was born in Pitschen, Upper Silesia (today Byczyna, Poland). He attended the University of Breslau from 1885 to 1890, and continued his studies in ...

describes the popular fourth-order Runge-Kutta method. * James Cullen, S.J., begins the study of

Cullen number In mathematics, a Cullen number is a member of the integer sequence C_n = n \cdot 2^n + 1 (where n is a natural number). Cullen numbers were first studied by James Cullen in 1905. The numbers are special cases of Proth numbers. Properties In ...

s. *

Emanuel Lasker Emanuel Lasker (; December 24, 1868 – January 11, 1941) was a German chess player, mathematician, and philosopher who was World Chess Champion for 27 years, from 1894 to 1921, the longest reign of any officially recognised World Chess Champ ...

proves the

Lasker–Noether theorem In mathematics, the Lasker–Noether theorem states that every Noetherian ring is a Lasker ring, which means that every ideal can be decomposed as an intersection, called primary decomposition, of finitely many '' primary ideals'' (which are relat ...

for the special case of

polynomial ring In mathematics, especially in the field of algebra, a polynomial ring or polynomial algebra is a ring (which is also a commutative algebra) formed from the set of polynomials in one or more indeterminates (traditionally also called variable ...

s. *

Karl Pearson Karl Pearson (; born Carl Pearson; 27 March 1857 – 27 April 1936) was an English mathematician and biostatistician. He has been credited with establishing the discipline of mathematical statistics. He founded the world's first university st ...

proposes the

random walk In mathematics, a random walk is a random process that describes a path that consists of a succession of random steps on some mathematical space. An elementary example of a random walk is the random walk on the integer number line \mathbb ...

in a letter to ''

Nature Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans ar ...

''.

Paleontology

* The Saurian Expedition led by John C. Merriam recovers many specimens of

ichthyosaur Ichthyosaurs (Ancient Greek for "fish lizard" – and ) are large extinct marine reptiles. Ichthyosaurs belong to the order known as Ichthyosauria or Ichthyopterygia ('fish flippers' – a designation introduced by Sir Richard Owen in 1842, altho ...

. * ''

Tyrannosaurus rex ''Tyrannosaurus'' is a genus of large theropod dinosaur. The species ''Tyrannosaurus rex'' (''rex'' meaning "king" in Latin), often called ''T. rex'' or colloquially ''T-Rex'', is one of the best represented theropods. ''Tyrannosaurus'' live ...

'' is described and named by

Henry Fairfield Osborn Henry Fairfield Osborn, Sr. (August 8, 1857 – November 6, 1935) was an American paleontologist, geologist and eugenics advocate. He was the president of the American Museum of Natural History for 25 years and a cofounder of the American E ...

Physics

Albert Einstein Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theor ...

(at this time resident in Bern) completes his doctoral thesis, ''A New Determination of Molecular Dimensions'' on April 30, submitting it to the

University of Zurich The University of Zürich (UZH, german: Universität Zürich) is a public research university located in the city of Zürich, Switzerland. It is the largest university in Switzerland, with its 28,000 enrolled students. It was founded in 1833 ...

on July 30, and publishes his four ''Annus Mirabilis'' papers in ''

Annalen der Physik ''Annalen der Physik'' (English: ''Annals of Physics'') is one of the oldest scientific journals on physics; it has been published since 1799. The journal publishes original, peer-reviewed papers on experimental, theoretical, applied, and mat ...

'' (Leipzig). Because of this, 1905 is said to be the miraculous year for

physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which rel ...

, and its 100th anniversary (

2005 File:2005 Events Collage V2.png, From top left, clockwise: Hurricane Katrina in the Gulf of Mexico; the Funeral of Pope John Paul II is held in Vatican City; "Me at the zoo", the first video ever to be uploaded to YouTube; Eris (dwarf planet), Er ...

) is declared the

World Year of Physics The year 2005 was named the World Year of Physics, also known as Einstein Year, in recognition of the 100th anniversary of Albert Einstein's " Miracle Year", in which he published four landmark papers, and the subsequent advances in the field of p ...

. ** "On a

Heuristic A heuristic (; ), or heuristic technique, is any approach to problem solving or self-discovery that employs a practical method that is not guaranteed to be optimal, perfect, or rational, but is nevertheless sufficient for reaching an immediat ...

Viewpoint Concerning the Production and Transformation of

Light Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 te ...

", received March 18 and published June 9, explains the

photoelectric effect The photoelectric effect is the emission of electrons when electromagnetic radiation, such as light, hits a material. Electrons emitted in this manner are called photoelectrons. The phenomenon is studied in condensed matter physics, and solid stat ...

through

quantum mechanics Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, q ...

. ** " Über die von der molekularkinetischen Theorie der Wärme geforderte Bewegung von in ruhenden Flüssigkeiten suspendierten Teilchen" ("On the Motion of Small Particles Suspended in a Stationary Liquid, as Required by the Molecular Kinetic Theory of Heat"), based on his doctoral research, received May 11 and published July 18, delineates a

stochastic Stochastic (, ) refers to the property of being well described by a random probability distribution. Although stochasticity and randomness are distinct in that the former refers to a modeling approach and the latter refers to phenomena themselve ...

model of

Brownian motion Brownian motion, or pedesis (from grc, πήδησις "leaping"), is the random motion of particles suspended in a medium (a liquid or a gas). This pattern of motion typically consists of random fluctuations in a particle's position insi ...

. ** "On the Electrodynamics of Moving Bodies", received June 30 and published September 26, formulates his theory of

special relativity In physics, the special theory of relativity, or special relativity for short, is a scientific theory regarding the relationship between space and time. In Albert Einstein's original treatment, the theory is based on two postulates: # The law ...

. ** "Does the Inertia of a Body Depend Upon Its Energy Content?", received September 27 and published November 21, deduces the law of

mass–energy equivalence In physics, mass–energy equivalence is the relationship between mass and energy in a system's rest frame, where the two quantities differ only by a multiplicative constant and the units of measurement. The principle is described by the physicis ...

, ''E'' = ''mc''².

Physiology and medicine

Nikolai Korotkov Nikolai Sergeyevich Korotkov (also romanized Korotkoff; russian: Никола́й Серге́евич Коротко́в) ( – 14 March 1920) was a Russian Empire surgeon, a pioneer of 20th-century vascular surgery, and the inventor of auscul ...

first describes

auscultatory blood pressure measurement Blood pressure (BP) is the pressure of circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term "blood pressure" r ...

. *

Karl Landsteiner Karl Landsteiner (; 14 June 1868 – 26 June 1943) was an Austrian-born American biologist, physician, and immunologist. He distinguished the main blood groups in 1900, having developed the modern system of classification of blood groups from ...

first describes Meconium ileus. *

Fritz Schaudinn Fritz Richard Schaudinn (19 September 1871 – 22 June 1906) was a German zoologist. Born in Röseningken, East Prussia, he co-discovered, with Erich Hoffmann in 1905, the causative agent of syphilis, ''Spirochaeta pallida'' (also known as ''Tr ...

and Erich Hoffmann discovered the bacterium that was responsible for syphilis, a spiral-shaped spirochete called

Treponema pallidum ''Treponema pallidum'', formerly known as ''Spirochaeta pallida'', is a spirochaete bacterium with various subspecies that cause the diseases syphilis, bejel (also known as endemic syphilis), and yaws. It is transmitted only among humans. It ...

Psychology

Sigmund Freud Sigmund Freud ( , ; born Sigismund Schlomo Freud; 6 May 1856 – 23 September 1939) was an Austrian neurologist and the founder of psychoanalysis, a clinical method for evaluating and treating psychopathology, pathologies explained as originatin ...

publishes ''Drei Abhandlungen zur Sexualtheorie'' (''

Three Essays on the Theory of Sexuality ''Three Essays on the Theory of Sexuality'' (german: Drei Abhandlungen zur Sexualtheorie), sometimes titled ''Three Contributions to the Theory of Sex'', is a 1905 work by Sigmund Freud, the founder of psychoanalysis, in which the author advance ...

'') and ''Der Witz und seine Beziehung zum Unbewußten'' (''

Jokes and their Relation to the Unconscious , translator = J. Strachey , image = Sigmund Freud Der Witz und seine Beziehung zum Unbewussten, 1905.png , caption = Jokes and Their Relation to the Unconscious , author = Sigmund Freud , illustrator = , cover_artist = , country =Germany an ...

''). * June –

Alfred Binet Alfred Binet (; 8 July 1857 – 18 October 1911), born Alfredo Binetti, was a French psychologist who invented the first practical IQ test, the Binet–Simon test. In 1904, the French Ministry of Education asked psychologist Alfred Binet to ...

and

Théodore Simon Théodore Simon (; 10 July 1873 – 4 September 1961) was a French psychologist who worked with Alfred Binet to develop the Binet-Simon scale, one of the most widely used scales in the world for measuring intelligence. This scale was revised i ...

publish the first Binet-Simon Intelligence Test for

intelligence test An intelligence quotient (IQ) is a total score derived from a set of standardized tests or subtests designed to assess human intelligence. The abbreviation "IQ" was coined by the psychologist William Stern for the German term ''Intelligen ...

ing of children with

mental retardation Intellectual disability (ID), also known as general learning disability in the United Kingdom and formerly mental retardation, Rosa's Law, Pub. L. 111-256124 Stat. 2643(2010). is a generalized neurodevelopmental disorder characterized by signif ...

Technology

* January 17 – Samuel J. Bens of San Francisco is granted the earliest patent for a practical " endless chain saw" for felling trees. *

Pathé Frères Pathé or Pathé Frères (, styled as PATHÉ!) is the name of various French businesses that were founded and originally run by the Pathé Brothers of France starting in 1896. In the early 1900s, Pathé became the world's largest film equipmen ...

colorise black-and-white films by machine. * Alfred Buchi files a patent for the

turbocharger In an internal combustion engine, a turbocharger (often called a turbo) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake gas, forcing more air into the engine in order to pr ...

. *

Paul de Vivie Paul de Vivie, who wrote as Vélocio
(April 29, 1853

invents a two-speed rear-wheel derailleur gear for bicycles. *

Pipe Pipe(s), PIPE(S) or piping may refer to: Objects * Pipe (fluid conveyance), a hollow cylinder following certain dimension rules ** Piping, the use of pipes in industry * Smoking pipe ** Tobacco pipe * Half-pipe and quarter pipe, semi-circul ...

manufactures the first

automobile A car or automobile is a motor vehicle with wheels. Most definitions of ''cars'' say that they run primarily on roads, seat one to eight people, have four wheels, and mainly transport people instead of goods. The year 1886 is regarded ...

with a

hemi engine A hemispherical combustion chamber is a type of combustion chamber in a reciprocating internal combustion engine with a domed cylinder head notionally in the approximate shape of a hemisphere (in reality usually a spheric section thereof). An e ...

. *

Walter Griffiths Walter Griffiths (4 July 1867 – 4 September 1900) was a politician in the Northern Territory of Australia. He was a member of the South Australian House of Assembly from 1893 to 1900, representing the Northern Territory electorate. Backgr ...

invents a manually powered domestic

vacuum cleaner A vacuum cleaner, also known simply as a vacuum or a hoover, is a device that causes suction in order to remove dirt from floors, upholstery, draperies, and other surfaces. It is generally electrically driven. The dirt is collected by either a ...

. *

Reginald Fessenden Reginald Aubrey Fessenden (October 6, 1866 – July 22, 1932) was a Canadian-born inventor, who did a majority of his work in the United States and also claimed U.S. citizenship through his American-born father. During his life he received hundre ...

invents the

superheterodyne receiver A superheterodyne receiver, often shortened to superhet, is a type of radio receiver that uses frequency mixing to convert a received signal to a fixed intermediate frequency (IF) which can be more conveniently processed than the original carr ...

. * Marconi invents the

directional antenna A directional antenna or beam antenna is an antenna which radiates or receives greater power in specific directions allowing increased performance and reduced interference from unwanted sources. Directional antennas provide increased performan ...

. * First

bascule bridge A bascule bridge (also referred to as a drawbridge or a lifting bridge) is a moveable bridge with a counterweight that continuously balances a span, or leaf, throughout its upward swing to provide clearance for boat traffic. It may be single- or ...

to the design of Joseph Strauss built. *

Canal Lake Concrete Arch Bridge Canal Lake Concrete Arch Bridge is an arch bridge in Ontario, Canada, spanning a portion of Canal Lake on the Trent–Severn Waterway between Balsam Lake and Lake Simcoe. It is north-northeast from the town of Bolsover. The closed spandrel bri ...

built in

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central C ...

Awards

Nobel Prize The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfre ...

s **

Physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which rel ...

–

Philipp Eduard Anton von Lenard Philipp Eduard Anton von Lenard (; hu, Lénárd Fülöp Eduárd Antal; 7 June 1862 – 20 May 1947) was a Hungarian-born German physicist and the winner of the Nobel Prize for Physics in 1905 for his work on cathode rays and the discovery o ...

** Chemistry –

Johann Friedrich Wilhelm Adolf von Baeyer Johann Friedrich Wilhelm Adolf von Baeyer (; 31 October 1835 – 20 August 1917) was a German chemist who synthesised indigo and developed a nomenclature for cyclic compounds (that was subsequently extended and adopted as part of the IUPAC org ...

Medicine Medicine is the science and Praxis (process), practice of caring for a patient, managing the diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, and Health promotion ...

– Robert Koch

Births

* February 1 –

Emilio Segrè Emilio Gino Segrè (1 February 1905 – 22 April 1989) was an Italian-American physicist and Nobel laureate, who discovered the elements technetium and astatine, and the antiproton, a subatomic antiparticle, for which he was awarded the N ...

(died

1989 File:1989 Events Collage.png, From left, clockwise: The Cypress structure collapses as a result of the 1989 Loma Prieta earthquake, killing motorists below; The proposal document for the World Wide Web is submitted; The Exxon Valdez oil tanker ru ...

), Italian-born

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate ca ...

, Nobel laureate * February 17 –

Rózsa Péter Rózsa Péter, born Rózsa Politzer, (17 February 1905 – 16 February 1977) was a Hungarian mathematician and logician. She is best known as the "founding mother of recursion theory". Early life and education Péter was born in Budapest, ...

(died

1977 Events January * January 8 – Three bombs explode in Moscow within 37 minutes, killing seven. The bombings are attributed to an Armenian separatist group. * January 10 – Mount Nyiragongo erupts in eastern Zaire (now the Democrati ...

), Hungarian

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...

, "founding mother of recursive function theory" * February 23 –

Derrick Henry Lehmer Derrick Henry "Dick" Lehmer (February 23, 1905 – May 22, 1991), almost always cited as D.H. Lehmer, was an American mathematician significant to the development of computational number theory. Lehmer refined Édouard Lucas' work in the 1930s and ...

(died

1991 File:1991 Events Collage.png, From left, clockwise: Boris Yeltsin, elected as Russia's first president, waves the new flag of Russia after the 1991 Soviet coup d'état attempt, orchestrated by Soviet hardliners; Mount Pinatubo erupts in the ...

), American

* March 18 –

Thomas Townsend Brown Thomas Townsend Brown (March 18, 1905 – October 27, 1985) was an American inventor whose research into odd electrical effects led him to believe he had discovered a connection between strong electric fields and gravity, a type of antigravity ...

(died

1985 The year 1985 was designated as the International Youth Year by the United Nations. Events January * January 1 ** The Internet's Domain Name System is created. ** Greenland withdraws from the European Economic Community as a result of a ...

), American inventor * March 26 –

Viktor Frankl Viktor Emil Frankl (26 March 1905 – 2 September 1997) was an Austrian psychiatrist who founded logotherapy, a school of psychotherapy that describes a search for a life's meaning as the central human motivational force. Logotherapy is par ...

(died

1997 File:1997 Events Collage.png, From left, clockwise: The movie set of ''Titanic'', the highest-grossing movie in history at the time; ''Harry Potter and the Philosopher's Stone'', is published; Comet Hale-Bopp passes by Earth and becomes one of ...

), Austrian

psychotherapist Psychotherapy (also psychological therapy, talk therapy, or talking therapy) is the use of psychological methods, particularly when based on regular personal interaction, to help a person change behavior, increase happiness, and overcome prob ...

* March 27 –

Elsie MacGill Elsie may refer to: People and fictional characters * Elsie (given name), a list of people and fictional characters * Lily Elsie (1886–1952), English actress and singer born Elsie Hodder * Robert Elsie (1950–2017), Canadian expert in Albanian ...

(died

1980 Events January * January 4 – U.S. President Jimmy Carter proclaims a United States grain embargo against the Soviet Union, grain embargo against the USSR with the support of the European Commission. * January 6 – Global Positioning Syst ...

), Canadian

aeronautical Aeronautics is the science or art involved with the study, design, and manufacturing of air flight–capable machines, and the techniques of operating aircraft and rockets within the atmosphere. The British Royal Aeronautical Society identifies ...

engineer Engineers, as practitioners of engineering, are professionals who invent, design, analyze, build and test machines, complex systems, structures, gadgets and materials to fulfill functional objectives and requirements while considering the l ...

, "Queen of the Hurricanes" * April 13 – Bruno Rossi (died

1993 File:1993 Events Collage.png, From left, clockwise: The Oslo I Accord is signed in an attempt to resolve the Israeli–Palestinian conflict; The Russian White House is shelled during the 1993 Russian constitutional crisis; Czechoslovakia is peace ...

), Italian physicist and

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either o ...

* April 18 – George H. Hitchings (died

1998 1998 was designated as the ''International Year of the Ocean''. Events January * January 6 – The ''Lunar Prospector'' spacecraft is launched into orbit around the Moon, and later finds evidence for frozen water, in soil in permanently s ...

), American scientist, Nobel laureate in Medicine * April 20 – Albrecht Unsöld (died

1995 File:1995 Events Collage V2.png, From left, clockwise: O.J. Simpson is acquitted of the murders of Nicole Brown Simpson and Ronald Goldman from the year prior in "The Trial of the Century" in the United States; The Great Hanshin earthquake strike ...

), German astronomer * July 7 – Marie-Louise Dubreil-Jacotin (died

1972 Within the context of Coordinated Universal Time (UTC) it was the longest year ever, as two leap seconds were added during this 366-day year, an event which has not since been repeated. (If its start and end are defined using Solar time, me ...

), French mathematician * August 1 –

Helen Sawyer Hogg Helen Battles Sawyer Hogg (August 1, 1905 – January 28, 1993) was an American-Canadian astronomer who pioneered research into globular clusters and variable stars. She was the first female president of several astronomical organizations and a ...

(died

), American-born astronomer * August 11 –

Erwin Chargaff Erwin Chargaff (11 August 1905 – 20 June 2002) was an Austro-Hungarian-born American biochemist, writer, Bucovinian Jew who emigrated to the United States during the Nazi era, and professor of biochemistry at Columbia University medical school ...

(died

2002 File:2002 Events Collage.png, From left, clockwise: The 2002 Winter Olympics are held in Salt Lake City; Queen Elizabeth The Queen Mother and her daughter Princess Margaret, Countess of Snowdon die; East Timor gains independence from Indonesia and ...

), Austro-Hungarian-born

biochemist Biochemists are scientists who are trained in biochemistry. They study chemical processes and chemical transformations in living organisms. Biochemists study DNA, proteins and cell parts. The word "biochemist" is a portmanteau of "biological che ...

* August 16 –

Marian Rejewski Marian Adam Rejewski (; 16 August 1905 – 13 February 1980) was a Polish mathematician and cryptography, cryptologist who in late 1932 reconstructed the sight-unseen German military Enigma machine, Enigma cipher machine, aided by limited docu ...

(died

), Polish mathematician and

cryptologist This is a list of cryptographers. Cryptography is the practice and study of techniques for secure communication in the presence of third parties called adversaries. Pre twentieth century * Al-Khalil ibn Ahmad al-Farahidi: wrote a (now lost) book ...

* August 31 –

Robert Bacher Robert Fox Bacher (August 31, 1905November 18, 2004) was an American nuclear physicist and one of the leaders of the Manhattan Project. Born in Loudonville, Ohio, Bacher obtained his undergraduate degree and doctorate from the University of ...

(died

2004 2004 was designated as an International Year of Rice by the United Nations, and the International Year to Commemorate the Struggle Against Slavery and its Abolition (by UNESCO). Events January * January 3 – Flash Airlines Flight 60 ...

), American

nuclear physicist Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter. Nuclear physics should not be confused with atomic physics, which studies the ...

* September 3 –

Carl David Anderson Carl David Anderson (September 3, 1905 – January 11, 1991) was an American physicist. He is best known for his discovery of the positron in 1932, an achievement for which he received the 1936 Nobel Prize in Physics, and of the muon in 1936. B ...

(died

), American physicist, Nobel laureate * September 17 –

Hans Freudenthal Hans Freudenthal (17 September 1905 – 13 October 1990) was a Jewish-German-born Dutch mathematician. He made substantial contributions to algebraic topology and also took an interest in literature, philosophy, history and mathematics edu ...

(died

1990 File:1990 Events Collage.png, From left, clockwise: The 1990 FIFA World Cup is played in Italy; The Human Genome Project is launched; Voyager I takes the famous Pale Blue Dot image- speaking on the fragility of Humankind, humanity on Earth, Astroph ...

), American mathematician * September 22 –

Eugen Sänger Eugen Sänger (22 September 1905 – 10 February 1964) was an Austrian aerospace engineer best known for his contributions to lifting body and ramjet technology. Early career Sänger was born in the former mining town of Preßnitz (Přísečni ...

(died

1964 Events January * January 1 – The Federation of Rhodesia and Nyasaland is dissolved. * January 5 - In the first meeting between leaders of the Roman Catholic and Orthodox churches since the fifteenth century, Pope Paul VI and Patriarc ...

), Austrian-born aerospace engineer * September 24 –

Severo Ochoa Severo Ochoa de Albornoz (; 24 September 1905 – 1 November 1993) was a Spanish physician and biochemist, and winner of the 1959 Nobel Prize in Physiology or Medicine together with Arthur Kornberg for their discovery of "the mechanisms in t ...

(died

), Spanish biochemist, Nobel laureate * September 30 –

Nevill Francis Mott Sir Nevill Francis Mott (30 September 1905 – 8 August 1996) was a British physicist who won the Nobel Prize for Physics in 1977 for his work on the electronic structure of magnetic and disordered systems, especially amorphous semiconductors. ...

(died

1996 File:1996 Events Collage.png, From left, clockwise: A bomb explodes at Centennial Olympic Park in Atlanta, set off by a radical anti-abortionist; The center fuel tank explodes on TWA Flight 800, causing the plane to crash and killing everyone on b ...

), English physicist, Nobel laureate * October 15 –

C. P. Snow Charles Percy Snow, Baron Snow, (15 October 1905 – 1 July 1980) was an English novelist and physical chemist who also served in several important positions in the British Civil Service and briefly in the UK government.''The Columbia Encyclop ...

(died

), English physicist and novelist * October 22 **

Karl Guthe Jansky Karl Guthe Jansky (October 22, 1905 – February 14, 1950) was an American physicist and radio engineer who in April 1933 first announced his discovery of radio waves emanating from the Milky Way in the constellation Sagittarius. He is considered ...

(died

1950 Events January * January 1 – The International Police Association (IPA) – the largest police organization in the world – is formed. * January 5 – Sverdlovsk plane crash: ''Aeroflot'' Lisunov Li-2 crashes in a snowstorm. All 19 ...

), American physicist **

Felix Bloch Felix Bloch (23 October 1905 – 10 September 1983) was a Swiss- American physicist and Nobel physics laureate who worked mainly in the U.S. He and Edward Mills Purcell were awarded the 1952 Nobel Prize for Physics for "their development of n ...

(died

1983 The year 1983 saw both the official beginning of the Internet and the first mobile cellular telephone call. Events January * January 1 – The migration of the ARPANET to TCP/IP is officially completed (this is considered to be the beginning ...

), Swiss

, Nobel laureate * October 31 –

Harry Harlow Harry Frederick Harlow (October 31, 1905 – December 6, 1981) was an American psychologist best known for his maternal-separation, dependency needs, and social isolation experiments on rhesus monkeys, which manifested the importance of caregivi ...

(died

1981 Events January * January 1 ** Greece enters the European Economic Community, predecessor of the European Union. ** Palau becomes a self-governing territory. * January 10 – Salvadoran Civil War: The FMLN launches its first major off ...

), American

psychologist A psychologist is a professional who practices psychology and studies mental states, perceptual, cognitive, emotional, and social processes and behavior. Their work often involves the experimentation, observation, and interpretation of how ...

* November 10 –

Louis Harold Gray Louis Harold Gray FRS (10 November 1905 – 9 July 1965) was an English physicist who worked mainly on the effects of radiation on biological systems. He was one of the earliest contributors of the field of radiobiology. A summary of his work ...

(died

1965 Events January–February * January 14 – The Prime Minister of Northern Ireland and the Taoiseach of the Republic of Ireland meet for the first time in 43 years. * January 20 ** Lyndon B. Johnson is Second inauguration of Lyndo ...

), English physicist, inventor of the field of

radiobiology Radiobiology (also known as radiation biology, and uncommonly as actinobiology) is a field of clinical and basic medical sciences that involves the study of the action of ionizing radiation on living things, especially health effects of radiation ...

* December 7 –

Gerard Kuiper Gerard Peter Kuiper (; ; born Gerrit Pieter Kuiper; 7 December 1905 – 23 December 1973) was a Dutch astronomer, planetary scientist, selenographer, author and professor. He is the eponymous namesake of the Kuiper belt. Kuiper i ...

(died

1973 Events January * January 1 - The United Kingdom, the Republic of Ireland and Denmark 1973 enlargement of the European Communities, enter the European Economic Community, which later becomes the European Union. * January 15 – Vietnam War: ...

), Dutch-born astronomer * December 16 – Piet Hein (died

), Danish mathematician * December 22 –

Tommy Flowers Thomas Harold Flowers MBE (22 December 1905 – 28 October 1998) was an English engineer with the British General Post Office. During World War II, Flowers designed and built Colossus, the world's first programmable electronic computer, to hel ...

(died

), English computer engineer

Deaths

* January 4 – Paul Henry (born

1848 1848 is historically famous for the wave of revolutions, a series of widespread struggles for more liberal governments, which broke out from Brazil to Hungary; although most failed in their immediate aims, they significantly altered the poli ...

), French

* January 14 –

Ernst Abbe Ernst Karl Abbe HonFRMS (23 January 1840 – 14 January 1905) was a German physicist, optical scientist, entrepreneur, and social reformer. Together with Otto Schott and Carl Zeiss, he developed numerous optical instruments. He was also a ...

(born

1840 Events January–March * January 3 – One of the predecessor papers of the ''Herald Sun'' of Melbourne, Australia, ''The Port Phillip Herald'', is founded. * January 10 – Uniform Penny Post is introduced in the United Kingdom. * Jan ...

), German physicist * March 24 –

Jules Verne Jules Gabriel Verne (;''Longman Pronunciation Dictionary''. ; 8 February 1828 – 24 March 1905) was a French novelist, poet, and playwright. His collaboration with the publisher Pierre-Jules Hetzel led to the creation of the ''Voyages extraord ...

(born

1828 Events January–March * January 4 – Jean Baptiste Gay, vicomte de Martignac succeeds the Comte de Villèle, as Prime Minister of France. * January 8 – The Democratic Party of the United States is organized. * January 22 – Arthu ...

), French

science fiction Science fiction (sometimes shortened to Sci-Fi or SF) is a genre of speculative fiction which typically deals with imagination, imaginative and futuristic concepts such as advanced science and technology, space exploration, time travel, Paral ...

author * April 14 –

Otto Wilhelm von Struve Otto Wilhelm von Struve (May 7, 1819 (Julian calendar: April 25) – April 14, 1905) was a Russian astronomer of Baltic German origins. In Russian, his name is normally given as Otto Vasil'evich Struve (Отто Васильевич Струв ...

(born

1819 Events January–March * January 2 – The Panic of 1819, the first major peacetime financial crisis in the United States, begins. * January 25 – Thomas Jefferson founds the University of Virginia. * January 29 – ...

), Russian

* June 18 –

Per Teodor Cleve Per Teodor Cleve (10 February 1840 – 18 June 1905) was a Swedish chemist, biologist, mineralogist and oceanographer. He is best known for his discovery of the chemical elements holmium and thulium. Born in Stockholm in 1840, Cleve earned his ...

(born

), Swedish

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe ...

* August 20 –

Franz Reuleaux Franz Reuleaux (; ; 30 September 1829 – 20 August 1905), was a German mechanical engineer and a lecturer of the Berlin Royal Technical Academy, later appointed as the President of the Academy. He was often called the father of kinematics. He ...

(born

1829 Events January–March * January 19 – August Klingemann's adaptation of Johann Wolfgang von Goethe's '' Faust'' premieres in Braunschweig. * February 27 – Battle of Tarqui: Troops of Gran Colombia and Peru battle to a draw. * ...

), German

mechanical engineer Mechanical may refer to: Machine * Machine (mechanical), a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement * Mechanical calculator, a device used to perform the basic operations o ...

* September 19 –

Thomas Barnardo Thomas John Barnardo (4 July 184519 September 1905) was an Irish-born philanthropist and founder and director of homes for poor and deprived children. From the foundation of the first Barnardo's home in 1867 to the date of Barnardo's death, nea ...

(born

1845 Events January–March * January 10 – Elizabeth Barrett receives a love letter from the younger poet Robert Browning; on May 20, they meet for the first time in London. She begins writing her ''Sonnets from the Portuguese''. * January ...

), Irish-born

physician A physician (American English), medical practitioner (Commonwealth English), medical doctor, or simply doctor, is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through th ...

and

philanthropist Philanthropy is a form of altruism that consists of "private initiatives, for the Public good (economics), public good, focusing on quality of life". Philanthropy contrasts with business initiatives, which are private initiatives for private goo ...

* October 6 –

Ferdinand von Richthofen Baron Ferdinand Freiherr von Richthofen (5 May 18336 October 1905), better known in English as was a German traveller, geographer, and scientist. He is noted for coining the terms "Seidenstraße" and "Seidenstraßen" = " Silk Road(s)" or "Silk ...

(born

1833 Events January–March * January 3 – Reassertion of British sovereignty over the Falkland Islands in the South Atlantic. * February 6 – His Royal Highness Prince Otto Friedrich Ludwig of Bavaria assumes the title His Majesty Othon t ...

), German

geologist A geologist is a scientist who studies the solid, liquid, and gaseous matter that constitutes Earth and other terrestrial planets, as well as the processes that shape them. Geologists usually study geology, earth science, or geophysics, alt ...

* November 14 –

Robert Whitehead Robert Whitehead (3 January 1823 – 14 November 1905) was an English engineer who was most famous for developing the first effective self-propelled naval torpedo. Early life He was born in Bolton, England, the son of James Whitehead, ...

(born

1823 Events January–March * January 22 – By secret treaty signed at the Congress of Verona, the Quintuple Alliance gives France a mandate to invade Spain for the purpose of restoring Ferdinand VII (who has been captured by armed revolution ...

), English marine engineer * November 15 (O.S. November 2) –

Ivan Sechenov Doctor Ivan Mikhaylovich Sechenov (russian: Ива́н Миха́йлович Се́ченов; , Tyoply Stan (now Sechenovo) near Simbirsk, Russia – , Moscow), was a Russian psychologist, physiologist, and medical scientist. The very fa ...

(born 1829), "the father of Russian

physiology Physiology (; ) is the scientific study of functions and mechanisms in a living system. As a sub-discipline of biology, physiology focuses on how organisms, organ systems, individual organs, cells, and biomolecules carry out the chemic ...

References

{{DEFAULTSORT:1905 In Science Science, 1905 In 20th century in science 1900s in science