The year 1921 in science and technology included many events, some of which are listed here. Wikimedia Commons has media related to: Science For the scientific journal named Science, see Science (journal). ... By the mid 20th century humans had achieved a level of technological mastery sufficient to leave the surface of the planet for the first time and explore space. ...

Chemistry

• Thomas Midgley discovers the effective anti-knocking properties of Tetra-ethyl lead, which is used in "leaded" gasoline (petrol).

Thomas Midgley, Jr. ... Tetra-ethyl lead (also known as TEL, lead tetraethyl and tetraethyllead) is a toxic organometallic chemical compound, with formula (CH3CH2)4Pb, which was once used as a gasoline (petrol) additive. ... Gasoline is a petroleum-derived liquid mixture consisting primarily of hydrocarbons, used as fuel in internal combustion engines. ...

Medicine

• July 18 - The first BCG vaccination against tuberculosis.
• July 27 - Researchers at the University of Toronto led by biochemist Frederick Banting announce the discovery of the hormone insulin.

July 18 is the 199th day (200th in leap years) of the year in the Gregorian Calendar, with 166 days remaining. ... Bacillus of Calmette and Guérin (BCG) is a vaccine against tuberculosis that is prepared from a strain of the attenuated (weakened) live bovine tuberculosis bacillus, Mycobacterium bovis that has lost its virulence in humans by specially culturing in artificial medium for years. ... Tuberculosis (commonly shortened to TB) is an infection caused by the bacterium Mycobacterium tuberculosis, which most commonly affects the lungs (pulmonary TB) but can also affect the central nervous system (meningitis), lymphatic system, circulatory system (Miliary tuberculosis), genitourinary system, bones and joints. ... July 27 is the 208th day (209th in leap years) of the year in the Gregorian Calendar, with 157 days remaining. ... Founded in 1827, the University of Toronto (U of T), in Toronto, Ontario, is the largest university in Canada. ... Biochemistry the chemistry of life, a bridge between biology and chemistry that studies how complex chemical reactions give rise to life. ... Sir Frederick Banting Sir Frederick Grant Banting, KBE , FRSC (November 14, 1891 – February 21, 1941) was a Canadian medical scientist, doctor and Nobel laureate noted as one of the co-discoverers of insulin. ... A hormone (from Greek horman - to set in motion) is a chemical messenger from one cell (or group of cells) to another. ... The structure of insulin Red: carbon; green: oxygen; blue: nitrogen; pink: sulfur. ...

Physics

• T. Kaluza demonstrates that a five-dimensional version of Albert Einstein's equations unifies gravitation and electromagnetism.

Albert Einstein photographed by Oren J. Turner in 1947. ... It has been suggested that this article or section be merged with Gravity. ... Electromagnetism is the physics of the electromagnetic field: a field, encompassing all of space, which exerts a force on those particles that possess a property known as electric charge, and is in turn affected by the presence and motion of such particles. ...

Awards

• Nobel Prize
  • Physics - Albert Einstein
  • Chemistry - Frederick Soddy
  • Physiology or Medicine - not awarded

This article does not cite its references or sources. ... List of Nobel Prize laureates in Physics from 1901 to the present day. ... Albert Einstein photographed by Oren J. Turner in 1947. ... List of Nobel Prize laureates in Chemistry from 1901 to the present day. ... Frederick Soddy (September 2, 1877 – September 22, 1956) was an English radiochemist. ... List of Nobel Prize laureates in Physiology or Medicine from 1901 to the present day. ...

Births

• May 21 - Andrei Sakharov (d. 1989), physicist, human rights activist, Nobel Laurette in Peace

May 21 is the 141st day of the year in the Gregorian calendar (142nd in leap years). ... Andrei Sakharov, 1943 Andrei Dmitrievich Sakharov (Андре́й Дми́триевич Са́харов, May 21, 1921 – December 14, 1989), was an eminent Soviet-Russian nuclear physicist, dissident and human rights activist. ... 1989 (MCMLXXXIX) is a common year starting on Sunday of the Gregorian calendar. ... A physicist is a scientist trained in physics. ... The Nobel Peace Prize (where Nobel is pronounced with the stress on the second syllable) is one of five Nobel Prizes bequested by the Swedish industrialist and inventor Alfred Nobel. ...

Deaths

• March 29 - John Burroughs (b. 1837), naturalist.
• October 23 - John Boyd Dunlop (b. 1840), inventor.