1802 in science
- March 28 – H. W. Olbers discovers the asteroid Pallas, the second known.
- Sir William Herschel first uses the term binary star to refer to a star which revolves around another star and coins the term asteroid.
- Pierre André Latreille begins publication of his Histoire naturelle générale et particulière des crustacés et insectes.
- George Montagu publishes his Ornithological Dictionary; or Alphabetical Synopsis of British Birds.
- In the history of evolutionary thought
- Jean-Baptiste Lamarck publishes Recherches sur l'Organisation des Corps Vivants, proposing that all life is organized in a vertical chain of progressive complexity.
- Gottfried Reinhold Treviranus begins publication of Biologie; oder die Philosophie der lebenden Natur, proposing a theory of the transmutation of species.
- July – William Hyde Wollaston notes the discovery of the noble metal palladium.
- Charles's law (the "law of volumes"), describing how gases tend to expand when heated, is first published in France by Joseph Louis Gay-Lussac.
- Thomas Wedgwood describes a method of creating (but not fixing) photographs using silver nitrate.
- Civil engineer and geographer François Antoine Rauch publishes Harmonie hydro-végétale et météorologique: ou recherches sur les moyens de recréer avec nos forêts la force des températures et la régularité des saisons par des plantations raisonnées in Paris, arguing against deforestation.
- James Smithson proves that zinc carbonates are true carbonate minerals and not zinc oxides, as was previously thought.
- John Playfair publishes Illustrations of the Huttonian Theory of the Earth in Edinburgh, popularising James Hutton's theory of geology.
- James Sowerby begins to issue his British Mineralogy, or, coloured figures intended to elucidate the mineralogy of Great Britain in London, the first comprehensive illustrated reference work on the subject.
- June – The first pediatric hospital, the Hôpital des Enfants Malades, opens in Paris, on the site of a previous orphanage.
- London Fever Hospital founded.
- Charles Bell publishes The Anatomy of the Brain, Explained in a Series of Engravings.
- December – Luke Howard presents the basis of the modern classification and nomenclature of clouds, at a lecture in London.
- April 10 – Great Trigonometric Survey of India begins with the measurement of a baseline near Madras.
- November 5 – Marc Isambard Brunel begins installation of his blockmaking machinery at Portsmouth Block Mills in England.
- George Bodley of Exeter in England patents the first enclosed kitchen stove.
- January 2 – Rev. Abraham Rees begins publication in London of The New Cyclopædia, or Universal Dictionary of Arts and Sciences.
- February 6 – Charles Wheatstone, English inventor (died 1875)
- April 4 – Dorothea Dix, American mental health reformer (died 1887)
- July 9 – Thomas Davenport, American inventor (died 1851)
- August 5 – Niels Henrik Abel, Norwegian mathematician (died 1829)
- October 10 – Hugh Miller, Scottish geologist (suicide 1856)
- December 15 – János Bolyai, Hungarian mathematician (died 1860)
- April 14 – John Mackay, Scottish botanist (born 1772)
- April 18 – Erasmus Darwin, English author of Zoonomia (born 1731)
- November 16 – André Michaux, French botanist (born 1746)
- Herschel, William (6 May 1802). "Observations on the two lately discovered celestial Bodies". JSTOR 107120.
- Hilton, James L. (2001-09-17). "When Did the Asteroids Become Minor Planets?". Archived from the original on 2010-01-18. Retrieved 2006-08-16.
- Osborn, Henry Fairfield (1905). From the Greeks to Darwin: an outline of the development of the evolution idea (2nd ed.). New York: Macmillan. p. 160.
- Gay-Lussac, J. L. "Recherches sur la dilatation des gaz et des vapeurs". Annales de chimie. XLIII: 137. Retrieved 29 September 2010.
- Williams, Hywel (2005). Cassell's Chronology of World History. London: Weidenfeld & Nicolson. p. 354. ISBN 0-304-35730-8.
- "Who was James Smithson? – A Man of Science". Smithsonian Institution. Archived from the original on 12 June 2007. Retrieved 2007-06-18.
- Smithson, James (1803). "A Chemical Analysis of Some Calamines". Philosophical Transactions of the Royal Society of London. Pt. I. Retrieved 25 February 2011.
- Ballbriga, Angel (1991). "One century of pediatrics in Europe". In Nichols, Buford L.; Ballabriga, A.; Kretchmer, N. History of Pediatrics 1850–1950. Nestlé Nutrition Workshop Series. 22. New York: Raven Press. pp. 6–8. ISBN 0-88167-695-0.
- Jacyna, L. S. (2004). "Bell, Sir Charles (1774–1842)". Oxford Dictionary of National Biography. Oxford University Press. doi:10.1093/ref:odnb/1999. Retrieved 2011-04-06. (subscription or UK public library membership required)
- Berg, Hermann (2008). "Johann Wilhelm Ritter: the Founder of Scientific Electrochemistry". Review of Polarography. 54 (2): 99–103. Retrieved 9 July 2010.[permanent dead link]
- Wetzels, Walter D. (1978). "J. W. Ritter: the Beginnings of Electrochemistry in Germany". In Dubpernell, G.; Westbrook, J. H. Selected Topics in the History of Electrochemistry. Princeton: Electrochemical Society. pp. 68–73.
- Bagust, Harold (2006). The Greater Genius? – a biography of Marc Isambard Brunel. Hersham: Ian Allan. p. 31. ISBN 978-0-7110-3175-3.
- Cornforth, David; Speight, Anne (2009-05-03). "Bodley & Co". Exeter Memories. Retrieved 2011-03-12.
- "The History of Ranges". Tarvin: Antique Fireplaces & Ranges. Retrieved 2011-03-12.
- Underwood, John (Spring–Summer 2010). "The subversive encyclopedia". Science Museum Library & Archives Newsletter. Science Museum at Wroughton. Archived from the original on 2011-01-17. Retrieved 2011-11-12.