Leo Scientists

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 1 
Steve Wozniak
(Co-Founder of Apple Inc.)
Steve Wozniak
13
Birthdate: August 11, 1950
Birthplace: San Jose, California, United States

Widely recognized as one of the two important pioneers of the personal computer revolution, Steve Wozniak is credited with co-founding Apple Inc. along with Steve Jobs. Not surprisingly, he has been described as one of the men that changed the course of history through technology. Apart from being a programmer and technology entrepreneur, Steve Wozniak is also a well-known philanthropist.

 2 
Alexander Fleming
(Physician and Microbiologist Who Discovered ‘Penicillin’ World’s First Broadly Effective Antibiotic Substance)
Alexander Fleming
7
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.

 3 
Erwin Schrödinger
8
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.
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 4 
Rosalind Franklin
10
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. 
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 5 
Robert Hooke
(Philosopher)
Robert Hooke
7
Birthdate: July 28, 1635
Birthplace: Freshwater, Isle of Wight
Died: March 3, 1703

Scientist Robert Hooke, also called England's Leonardo, initially gained recognition as an architect, conducting surveys following the Great Fire of London. He also taught geometry and was part of the Royal Society. He assisted Robert Boyle and eventually developed his own microscope, thus becoming the first to visualize micro-organisms.

 6 
Paul Dirac
(One of the Most Significant Physicists of the 20th Century and Nobel Laureate)
Paul Dirac
9
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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 7 
Amedeo Avogadro
(Chemist and Physicist)
Amedeo Avogadro
9
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.

 8 
Louis de Broglie
(Physicist)
Louis de Broglie
7
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.

 9 
Hans Christian Ørsted
5
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.

 10 
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.

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 11 
Vera Rubin
(American Astronomer Known for Her Pioneering Work on Galaxy Rotation Rates)
Vera Rubin
6
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.

 12 
Sir William Rowan Hamilton
(Irish Mathematician and Astronomer Who Contributed to the Development of ‘Optics’, ‘Classical Mechanics’ and ‘Abstract Algebra’)
Sir William Rowan Hamilton
4
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.

 13 
Marvin Minsky
(Mathematician, Computer scientist, University teacher)
Marvin Minsky
15
Birthdate: August 9, 1927
Birthplace: New York City
Died: January 24, 2016
 14 
Augustin-Louis Cauchy
(Mathematician)
Augustin-Louis Cauchy
4
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.

 15 
Niels Henrik Abel
(Mathematician)
Niels Henrik Abel
3
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.

 16 
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.

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 17 
Roger Penrose
(Mathematician)
Roger Penrose
14
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.

 18 
Stephanie Kwolek
5
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.

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 19 
John Logie Baird
6
Birthdate: August 13, 1888
Birthplace: Helensburgh
Died: June 14, 1946

Scottish inventor, electrical engineer, and innovator, John Logie Baird, is best known for demonstrating a working TV system in 1926. He then went on to invent the first viable purely electronic color TV picture tube and founded the Baird Television Development Company. He was inducted into the Scottish Engineering Hall of Fame in 2015.

 20 
Ernest Lawrence
(Physicist)
Ernest Lawrence
3
Birthdate: August 8, 1901
Birthplace: Canton, South Dakota, United States
Died: August 27, 1958
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 21 
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.

 22 
John G. Trump
(Scientist)
John G. Trump
7
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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 23 
Hilary Putnam
(Mathematician, Philosopher)
Hilary Putnam
4
Birthdate: July 31, 1926
Birthplace: Chicago, Illinois, United States
Died: March 13, 2016
 24 
Vikram Sarabhai
(Scientist)
Vikram Sarabhai
4
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.

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 25 
Margaret Hamilton
(American Computer Scientist, Systems Engineer, and Business Owner)
Margaret Hamilton
9
Birthdate: August 17, 1936
Birthplace: Paoli, Indiana, United States

Credited with coining the term software engineering, computer scientist and systems engineer, Margaret Heafield Hamilton served as the Director of the Software Engineering Division of the MIT Instrumentation Laboratory, overseeing the development of the on-board flight software for NASA's Apollo program.  A prolific writer, she is also the founder of two software companies; Higher Order Software and Hamilton Technologies.

 26 
Wade Barrett
(Professional wrestler, Marine biologist)
Wade Barrett
5
Birthdate: August 10, 1980
Birthplace: Preston
 27 
Wilhelm Wundt
(Philosopher)
Wilhelm Wundt
5
Birthdate: August 16, 1832
Birthplace: Mannheim, Germany
Died: August 31, 1920

Wilhelm Wundt was a German physiologist, professor, and philosopher. He is often counted among the founders of modern psychology and is widely considered the father of experimental psychology. He is also credited with founding the first laboratory for psychological research, which he founded at the University of Leipzig in 1879.

 28 
Jean-Baptiste Lamarck
(Naturalist and Biologist Best Known for Proposing that Acquired Characteristics can be Inherited.)
Jean-Baptiste Lamarck
5
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.

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 29 
Antoine-Augustin Parmentier
(Botanist, Pharmacist, Physician, Agronomist, Nutritionist)
Antoine-Augustin Parmentier
7
Birthdate: August 12, 1737
Birthplace: Montdidier
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.

 30 
John Carmack
(Chief technology officer, Aerospace engineer, Programmer, Computer scientist)
John Carmack
9
Birthdate: August 20, 1970
Birthplace: Kansas City

Computer-game developer John Carmack introduced pioneering innovations in the 3-D game arena. He specializes in first-person shooter games, such as Quake and Doom. The id Software founder had spent a year in a juvenile home and had later dropped out of university to become a freelance programmer.

 31 
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.

 32 
John B. Goodenough
4
Birthdate: July 25, 1922
Birthplace: Jena, Germany

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.

 33 
Frances Oldham Kelsey
(Canadian-American Pharmacologist Known for Preventing 'Thalidomide' From Being Marketed in the United States)
Frances Oldham Kelsey
4
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.

 34 
Arthur Cayley
(Mathematician)
Arthur Cayley
3
Birthdate: August 16, 1821
Birthplace: Richmond, Surrey, UK
Died: January 26, 1895
 35 
Manjul Bhargava
(Mathematician)
Manjul Bhargava
7
Birthdate: August 8, 1974
Birthplace: Hamilton, Canada
 36 
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.

 37 
Sudha Murty
(Author)
Sudha Murty
7
Birthdate: August 19, 1950
Birthplace: Shiggaon, Haveri, Karnataka, India

Known for her humility and simplicity, Indian philanthropist and author Sudha Murty had humble beginnings as a TELCO engineer. She is married to Infosys co-founder Narayan Murty and heads the Infosys Foundation. The Padma Shri winner has penned over 200 titles, such as Dollar Bahu, in both Kannada and English.

 38 
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.

 39 
Gifford Pinchot
(First Chief of the US Forest Service & Former Governor of Pennsylvania)
Gifford Pinchot
6
Birthdate: August 11, 1865
Birthplace: Simsbury, Connecticut, United States
Died: October 4, 1946

Gifford Pinchot was an American politician and forester. He is best remembered for his service as the first chief of the US Forest Service from February 1905 to January 1910. Gifford Pinchot also served as the Governor of Pennsylvania on two occasions; from 16 January 1923 to 18 January 1927 and again from 20 January 1931 to 15 January 1935.

 40 
Thomas Telford
(Civil Engineer)
Thomas Telford
3
Birthdate: August 9, 1757
Birthplace: Eskdale, Dumfriesshire, Scotland
Died: September 2, 1834

Scottish civil engineer Thomas Telford had begun his career as a mason at 14, having lost his father in infancy. A self-taught architect, he was responsible for building many structures, including the Caledonian Canal and the Menai Suspension Bridge. Named The Colossus of Roads, he symbolized the Scottish Enlightenment.

 41 
M. S. Swaminathan
(Agricultural Scientist)
M. S. Swaminathan
13
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.

 42 
Luc Montagnier
(Virologist & Discoverer of HIV)
Luc Montagnier
7
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.

 43 
James Lovelock
(Biologist, Chemist, University teacher, Mythographer)
James Lovelock
4
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.

 44 
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.

 45 
John Venn
(Mathematician)
John Venn
4
Birthdate: August 4, 1834
Birthplace: Kingston upon Hull
Died: April 4, 1923
 46 
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.

 47 
Luis von Ahn
(Entrepreneur)
Luis von Ahn
3
Birthdate: August 9, 1978
Birthplace: Guatemala City, Guatemala
 48 
John Tyndall
(Physicist)
John Tyndall
3
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.

 49 
Story Musgrave
(Astronaut, Statistician, Aviator, Officer)
Story Musgrave
5
Birthdate: August 19, 1935
Birthplace: Boston
 50 
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.