Leo Scientists

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 1 
Alexander Fleming
(Physician and Microbiologist Who Discovered ‘Penicillin’ World’s First Broadly Effective Antibiotic Substance)
Alexander Fleming
15
Birthdate: August 6, 1881
Birthplace: Darvel, East Ayrshire, Scotland
Died: March 11, 1955

Alexander Fleming was a Scottish microbiologist and physician. He is credited with discovering penicillin, the world's first effective antibiotic substance; a discovery that changed the course of history. He also discovered lysozyme, an antimicrobial enzyme which forms part of the innate immune system. In 1999, Fleming was named in Time magazine's 100 Most Important People of the 20th century list.

 2 
Erwin Schrödinger
(Austrian Physicist Who Made Important Contributions to the Development of Quantum Mechanics)
Erwin Schrödinger
11
Birthdate: August 12, 1887
Birthplace: Erdberg, Vienna, Austria
Died: January 4, 1961
Austrian physicist Erwin Schrödinger, is best known for the "Schrödinger's cat" experiment, or the Schrodinger equation. His book What Is Life? explored genetics through physics. The Nobel Prize winner also wrote on a variety of topics, such as color theory and thermodynamics, and tried to create a unified field theory.
 3 
Paul Dirac
(One of the Most Significant Physicists of the 20th Century and Nobel Laureate)
Paul Dirac
11
Birthdate: August 8, 1902
Birthplace: Bristol, England
Died: October 20, 1984

English theoretical physicist and Nobel laureate Paul Dirac OM FRS, counted among leading physicists of the 20th century, made fundamental contributions in the early development of quantum electrodynamics and quantum mechanics. He derived the Dirac equation while the modern theory of antimatter began with one of his papers. His book The Principles of Quantum Mechanics remains an influential monograph on the subject.

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 4 
Amedeo Avogadro
(Chemist and Physicist)
Amedeo Avogadro
11
Birthdate: August 9, 1776
Birthplace: Turin, Italy
Died: July 9, 1856

Son of a reputed senator and lawyer in Italy, Amedeo Avogadro was himself a qualified lawyer. However, he later delved into research as a mathematical physicist and is best remembered for laying down the Avogadro’s law, contributing to the molecular theory of gases. The Avogadro constant is named after him.

 5 
Louis de Broglie
(Physicist)
Louis de Broglie
8
Birthdate: August 15, 1892
Birthplace: Dieppe
Died: March 19, 1987

Louis de Broglie was a French aristocrat and physicist who made important contributions to quantum theory. His de Broglie hypothesis, which suggests that all matter has wave properties, is one of the most important features in the theory of quantum mechanics. In 1929, de Broglie was honored with the Nobel Prize for Physics for his work.

 6 
Hans Christian Ørsted
9
Birthdate: August 14, 1777
Birthplace: Rudkøbing
Died: March 9, 1851

Hans Christian Ørsted was a Danish chemist and physicist. He was the first person to discover that electric currents can be used to create magnetic fields. His discovery was the first relationship found between magnetism and electricity. Oersted, the unit of the auxiliary magnetic field H, is named in his honor.

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 7 
Marvin Minsky
(Mathematician, Computer scientist, University teacher)
Marvin Minsky
16
Birthdate: August 9, 1927
Birthplace: New York City
Died: January 24, 2016
 8 
Frederick Sanger
(Biochemist)
Frederick Sanger
4
Birthdate: August 13, 1918
Birthplace: Rendcomb
Died: November 19, 2013

Frederick Sanger remains one of only two people to have won the Nobel Prize twice in the same category. The British biochemist is remembered for his ground-breaking work on nucleic acids and the insulin molecule. The son of a Quaker medical missionary, Sanger, too, grew up believing in Quakerism.

 9 
Vera Rubin
(American Astronomer Known for Her Pioneering Work on Galaxy Rotation Rates)
Vera Rubin
9
Birthdate: July 23, 1928
Birthplace: Philadelphia, Pennsylvania, United States
Died: December 25, 2016

American astronomer Vera Rubin is best known for her pioneering discoveries on galaxy rotation rates, her groundbreaking work confirming the existence of dark matter and for her life-long advocacy for women in science. She studied the galactic rotation curves and provided strong evidence of the existence of dark matter. The Vera C. Rubin Observatory in Chile is named after her.

 10 
Sir William Rowan Hamilton
(Irish Mathematician and Astronomer Who Contributed to the Development of ‘Optics’, ‘Classical Mechanics’ and ‘Abstract Algebra’)
Sir William Rowan Hamilton
6
Birthdate: August 4, 1805
Birthplace: Dublin, Ireland
Died: September 2, 1865

Son of a Dublin solicitor, Sir William Rowan Hamilton was raised and educated by his priest uncle from age 3. Initially a master of languages such as Latin, Greek, and Persian, Hamilton began deviating to math at 16. He is remembered for his contribution to optics, Hamiltonian mechanics, and algebra.

 11 
Augustin-Louis Cauchy
(Mathematician)
Augustin-Louis Cauchy
5
Birthdate: August 21, 1789
Birthplace: Paris
Died: May 23, 1857

French mathematician Augustin-Louis Cauchy was initially a military engineer. In his early days, he and his family escaped the Reign of Terror and settled in Arcueil. He was one of the pioneers of mathematical analysis and made significant contributions to subjects such as error theory, calculus, and complex functions.

 12 
Niels Henrik Abel
(Mathematician)
Niels Henrik Abel
4
Birthdate: August 5, 1802
Birthplace: Finnøy
Died: April 6, 1829

Born to a pastor, Norwegian mathematician Niels Henrik Abel first showcased his mathematical skills in his cathedral school and later became a pioneer of various mathematical concepts. He died of tuberculosis, amid poverty, before he could learn that he had been appointed to teach at the University of Berlin.

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 13 
Hilary Putnam
(Mathematician, Philosopher)
Hilary Putnam
5
Birthdate: July 31, 1926
Birthplace: Chicago, Illinois, United States
Died: March 13, 2016
 14 
Johann Bernoulli
(Mathematician)
Johann Bernoulli
3
Birthdate: August 6, 1667
Birthplace: Basel
Died: January 1, 1748

Brother and colleague of Swiss mathematician Jacob Bernoulli and part of the famous Bernoulli family of mathematicians, Johann Bernoulli was initially pushed to join his family business of drug and spices. He later took up medicine, eventually deviating to math and contributing to infinitesimal calculus, along with Jacob.

 15 
Roger Penrose
(English Mathematician, Mathematical Physicist and Winner of the 2020 Nobel Prize for Physics)
Roger Penrose
16
Birthdate: August 8, 1931
Birthplace: Colchester, England

Roger Penrose’s contribution to the research related to the black hole and general relativity earned him the Nobel Prize in Physics in 2020. The Emeritus Rouse Ball Professor of Mathematics at Oxford, Roger is also a fellow of Wadham College, St John's College of Cambridge, and University College London.

 16 
Ernest Lawrence
(Physicist)
Ernest Lawrence
3
Birthdate: August 8, 1901
Birthplace: Canton, South Dakota, United States
Died: August 27, 1958
 17 
Stephanie Kwolek
7
Birthdate: July 31, 1923
Birthplace: New Kensington, Pennsylvania, United States
Died: June 18, 2014

Stephanie Kwolek was an American chemist remembered for her invention of Kevlar. She worked at the DuPont Company for over four decades and was awarded the company's Lavoisier Medal for her discovery. In 1995, she was inducted into the National Inventors Hall of Fame, becoming the fourth woman to be inducted. She also won other awards including the Perkin Medal.

 18 
Luc Montagnier
(French Virologist & Discoverer of HIV)
Luc Montagnier
8
Birthdate: August 18, 1932
Birthplace: Chabris, France
Died: February 8, 2022

French virologist Luc Montagnier is known for discovering the human immunodeficiency virus (HIV) which led him to jointly receive the 2008 Nobel Prize in Physiology or Medicine. Montagnier also made headlines promoting controversial and unverified claims related to vaccinations, homeopathy and COVID-19 pandemic, which he argued as man-made and possibly a result of an attempt to create an HIV/AIDS vaccine.

 19 
Jöns Jacob Berzelius
(Chemist, Non-fiction writer, University teacher)
Jöns Jacob Berzelius
3
Birthdate: August 20, 1779
Birthplace: Östergötland
Died: August 7, 1848

Jöns Jacob Berzelius was a Swedish chemist who is often counted among the founders of modern chemistry alongside Robert Boyle, Antoine Lavoisier, and John Dalton. He is also referred to as the Father of Swedish Chemistry. Jöns Jacob Berzelius is also credited with making immense contributions to the field of stoichiometry. In 1836, he was honored with the Copley Medal.

 20 
Vikram Sarabhai
(Scientist)
Vikram Sarabhai
5
Birthdate: August 12, 1919
Birthplace: Ahmedabad, India
Died: December 30, 1971

Padma Bhushan- and Padma Vibhushan-winning Indian scientist Vikram Sarabhai was born into the famous Sarabhai family of industrialists who were associated with the Indian Independence Movement. He made major contributions to India’s nuclear power and space research initiatives, developed textile research in India, and helped set up IIM-Ahmedabad.

 21 
John G. Trump
(Scientist)
John G. Trump
9
Birthdate: August 21, 1907
Birthplace: New York, New York, United States
Died: February 21, 1985

Better known as former U.S. president Donald Trump’s uncle, John G. Trump was an MIT physicist and engineer. Though he had initially aspired to be an architect and join his brother Fred’s real-estate business, John later concentrated on his research that led to the invention of high-voltage generators.

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 22 
Rosalind Franklin
14
Birthdate: July 25, 1920
Birthplace: Notting Hill, London, England
Died: April 16, 1958
Chemist and X-ray crystallographer Rosalind Franklin is remembered for her pathbreaking X-ray diffraction studies of DNA, which helped in the Nobel Prize-winning discovery of the double helix structure of DNA by Francis Crick, James Watson, and Maurice Wilkins later. She also worked on the molecular structures of viruses. 
 23 
Jean-Baptiste Lamarck
(Naturalist and Biologist Best Known for Proposing that Acquired Characteristics can be Inherited.)
Jean-Baptiste Lamarck
6
Birthdate: August 1, 1744
Birthplace: Bazentin, France
Died: December 18, 1829

French biologist Jean-Baptiste Lamarck acquired his love for plants while serving as a soldier in the French army. Following an injury, he quit his military career but retained his love for botany. He later taught zoology, studied the classification of invertebrates, and also coined the term biology.

 24 
John B. Goodenough
(Physicist Known for Pioneering Work in the Development of Lithium-Ion Battery)
John B. Goodenough
4
Birthdate: July 25, 1922
Birthplace: Jena, Germany
Died: June 25, 2023

John B. Goodenough is an American solid-state physicist and materials scientist. He is credited with developing the lithium-ion battery. In 2019, he became the oldest person to receive a Nobel Prize when he was honored with the prestigious award for his work on lithium-ion batteries. He is also a recipient of the Copley Medal and the National Medal of Science.

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 25 
Antoine-Augustin Parmentier
(French Pharmacist and Agronomist)
Antoine-Augustin Parmentier
8
Birthdate: August 12, 1737
Birthplace: Montdidier, France
Died: December 17, 1813

While in prison, in the aftermath of the Seven Years’ War, army pharmacist Antoine-Augustin Parmentier was forced to eat potatoes, which were considered fit only for prison ration and animal feed back then. Parmentier later persuaded the Paris Faculty of Medicine to declare potatoes edible and popularized them in France.

 26 
Frances Oldham Kelsey
(Canadian-American Pharmacologist Known for Preventing 'Thalidomide' From Being Marketed in the United States)
Frances Oldham Kelsey
6
Birthdate: July 24, 1914
Birthplace: Cobble Hill, British Columbia, Canada
Died: August 7, 2015

As part of the FDA, Frances Oldham Kelsey prevented thalidomide from being allowed in the US drug market as a painkiller, as she was unsure of its impact. Her concerns were proved right when the drug caused birth defects in European children. She was subsequently awarded by the US president.

 27 
Arthur Cayley
(Mathematician)
Arthur Cayley
3
Birthdate: August 16, 1821
Birthplace: Richmond, Surrey, UK
Died: January 26, 1895
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 28 
George de Hevesy
(Hungarian Radiochemist Known for His Key Role in the Development of 'Radioactive Tracers')
George de Hevesy
5
Birthdate: August 1, 1885
Birthplace: Budapest, Hungary
Died: July 5, 1966

Nobel Prize-winning Hungarian-Swedish chemist George de Hevesy is best remembered for his research on isotopic tracer techniques to study animal metabolism. He is also credited with co-discovering the element hafnium with physicist Dirk Coster. He fled the Nazi regime and moved first to Denmark and then to Sweden.

 29 
Manjul Bhargava
(Mathematician)
Manjul Bhargava
10
Birthdate: August 8, 1974
Birthplace: Hamilton, Canada
 30 
Friedrich Wöhler
(German chemist)
Friedrich Wöhler
4
Birthdate: July 31, 1800
Birthplace: Eschersheim
Died: September 23, 1882

Friedrich Wöhler was a German chemist best remembered for his contribution to the field of inorganic chemistry. He was the first person to isolate the chemical elements yttrium and beryllium in pure metallic form. Friedrich Wöhler was also the first person to prepare many inorganic compounds such as silicon nitride and silane.

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 31 
Clive Sinclair
(Entrepreneur, Engineer, Inventor, Computer scientist)
Clive Sinclair
3
Birthdate: July 30, 1940
Birthplace: Surrey

A consumer electronics pioneer, entrepreneur Clive Sinclair began his business venture selling radio and amplifier kits. He went on to launch the word’s first pocket calculator and later also worked on products such as digital watches and pocket TV. He is a fan of poker and is a Mensa member.

 32 
James Lovelock
(Biologist, Chemist, University teacher, Mythographer)
James Lovelock
5
Birthdate: July 26, 1919
Birthplace: Letchworth

Renowned James Lovelock is best known for propagating the Gaia hypothesis, which states that every living being on planet Earth is part of a single self-regulating superorganism. He is also known for his long association with NIMR, London, and Harvard University and has over 50 patents under his name.

 33 
M. S. Swaminathan
(Indian Agronomist Who is Known as the Main Architect of the Green Revolution in India)
M. S. Swaminathan
14
Birthdate: August 7, 1925
Birthplace: Kumbakonam, India

Ramon Magsaysay Award-winning geneticist M. S. Swaminathan is best known for his contribution to the Indian Green Revolution. Featured on Time, he introduced high-yielding varieties of wheat and rice seedlings to Indian farmers. He is also known for his administrative work as part of the Indian civil services.

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 34 
Sidney Gottlieb
(American Chemist and Spymaster Who Headed Project Mkultra)
Sidney Gottlieb
5
Birthdate: August 3, 1918
Birthplace: New York City, New York, United States
Died: March 7, 1999

Sidney Gottlieb was an American spymaster and chemist who played a major role in the CIA's mind-control program and assassination attempts during the 1950s and 1960s; the illegal human experimentation program which he headed was called Project MKUltra.

 35 
Erwin Chargaff
( Austro-Hungarian Biochemist Who Emigrated to America During the Nazi Era)
Erwin Chargaff
5
Birthdate: August 11, 1905
Birthplace: Chernivtsi, Ukraine
Died: June 20, 2002

Erwin Chargaff was a biochemist and writer who worked at the Columbia University medical school as a professor of biochemistry. He is credited with discovering the Chargaff's rules, which played an important role in the discovery of the DNA's double helix structure. Also a prolific writer, Erwin Chargaff authored several books, including an autobiography.

 36 
John Venn
(Mathematician)
John Venn
4
Birthdate: August 4, 1834
Birthplace: Kingston upon Hull
Died: April 4, 1923
 37 
Story Musgrave
(US Physician and NASA Astronaut Who Became the 2nd Person to Make 6 Space Flights)
Story Musgrave
5
Birthdate: August 19, 1935
Birthplace: Boston

US physician and astronaut Story Musgrave initially worked for the US Marine Corps. Before joining NASA, he gained a host of degrees, in subjects such as literature, math, and chemistry, and an MD from Columbia University. He became the 2nd astronaut to make 6 space flights and later worked for Imagineering and Applied Minds.

 38 
Ettore Majorana
(Physicist)
Ettore Majorana
3
Birthdate: August 5, 1906
Birthplace: Catania

Ettore Majorana was immensely talented in math and grew up to be a theoretical physics professor. He also worked on neutrino masses but abruptly disappeared while on a ship from Palermo to Naples. People have come up with theories such as suicide and murder to explain his disappearance.

 39 
John Tyndall
(Irish Experimental Physicist Who Became Famous for His Study of Dimagnetism)
John Tyndall
4
Birthdate: August 2, 1820
Birthplace: Leighlinbridge, Ireland
Died: December 4, 1893

Born into a poor Protestant family, Irish physicist John Tyndall was a self-made man who funded his own doctoral education. His contributions include his research on the greenhouse effect and the discovery of the Tyndall effect. Not known to many, he was also an avid mountaineer and glaciologist.

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 40 
Edward O. Thorp
(Mathematician, Writer, University teacher)
Edward O. Thorp
5
Birthdate: August 14, 1932
Birthplace: Chicago
 41 
Edgar F. Codd
(British Computer Scientist and Mathematician Who Devised the ‘Relational Data Model')
Edgar F. Codd
3
Birthdate: August 19, 1923
Birthplace: Fortuneswell, England
Died: April 18, 2003

Turing Award-winning computer scientist Edgar F. Codd is best remembered for his relational data model, which contributed to the development of the relational database used in storing and retrieving computer data. An Oxford graduate, he had also worked for the army during World War II.

 42 
Marian Rejewski
(Polish Mathematician and Cryptologist Known for Solving the Enigma-machine cipher)
Marian Rejewski
5
Birthdate: August 16, 1905
Birthplace: Bydgoszcz, Poland
Died: February 13, 1980

Polish mathematician-cryptologist Marian Rejewski is noted for reconstructing the sight-unseen German military Enigma cipher machine and solving Enigma-machine cipher using limited documents that the French military intelligence managed to obtain. He and his colleagues developed and applied methods and equipment for decrypting the German machine ciphers which gave Britain an opportunity to read German Enigma-encrypted messages during Second World War.   

 43 
George M. Whitesides
(Chemist and professor of chemistry at Harvard University)
George M. Whitesides
3
Birthdate: August 3, 1939
Birthplace: Louisville, Kentucky, United States
 44 
Ernest Everett Just
3
Birthdate: August 14, 1883
Birthplace: Charleston, South Carolina, United States
Died: October 27, 1941

Ernest Everett Just was an African-American biologist and academic. He is credited with recognizing the fundamental role of the cell surface in the development of organisms. As a black boy growing up in the late 19th century, he had to face enormous challenges before he could establish himself in his career. He co-founded the Omega Psi Phi Fraternity, Inc.  

 45 
Sir George Stokes, 1st Baronet
(Irish English Physicist and Mathematician)
Sir George Stokes, 1st Baronet
4
Birthdate: August 13, 1819
Birthplace: Skreen, Ireland
Died: February 1, 1903

Sir George Stokes, 1st Baronet was an Anglo-Irish physicist and mathematician. He studied at Pembroke College, Cambridge, and spent his entire career at the University of Cambridge as the Lucasian Professor of Mathematics. As a physicist, he made key contributions to fluid mechanics and physical optics. He received the Royal Society's Copley Medal in 1893.

 46 
Gerty Cori
(Biochemist)
Gerty Cori
3
Birthdate: August 15, 1896
Birthplace: Prague, Czechia
Died: October 26, 1957

Austro-Hungarian-American biochemist Gerty Cori is best-known for discovering the course of catalytic conversion of glycogen with her husband Carl Ferdinand Cori for which they jointly won the 1947 Nobel Prize in Physiology or Medicine. With this Gerty became the third woman to win a Nobel in science and the first to win it in this category.

 47 
Ilya Ivanovich Ivanov
(Biologist)
Ilya Ivanovich Ivanov
3
Birthdate: August 1, 1870
Birthplace: Shchigry
Died: March 20, 1932
 48 
Isidor Isaac Rabi
3
Birthdate: July 29, 1898
Birthplace: Rymanów, Galicia, Austria-Hungary (today Poland)
Died: January 11, 1988
 49 
Maria Mitchell
(Astronomer)
Maria Mitchell
3
Birthdate: August 1, 1818
Birthplace: Nantucket
Died: June 28, 1889
Maria Mitchell was motivated by her amateur astronomer father to venture into astronomy, and he taught her to operate several astronomical instruments. She later grew up to be America’s first professional female astronomer and is best remembered for discovering the comet 1847 VI, also known as Miss Mitchell's Comet.
 50 
Edward Drinker Cope
(American Zoologist and Paleontologist)
Edward Drinker Cope
3
Birthdate: July 28, 1840
Birthplace: Philadelphia, Pennsylvania, United States
Died: April 12, 1897