Famous American Scientists Of The 20th Century
The 20th century America was one of the major hubs of scientific and technological developments in the world. In the early part of the century, many prominent European scientists including Hans Bethe, Albert Einstein, Enrico Fermi, Leó Szilárd, Edward Teller, and Felix Bloch migrated to the United States where they accomplished several important achievements. During this era, scientists in the US made one highly controversial yet commendable accomplishment—the harnessing of nuclear energy. Gerald Woodrow Johnson, William Howard Arnold, and Charles Kincaid Bockelman were some of the established nuclear scientists of 20th century. America was also a pioneer in computer technology and information technology. Pioneers like John McCarthy who was one of the founders of the discipline of artificial intelligence played a major role in accelerating America’s progress in the area of computer science. Grace Brewster Murray Hopper, born in the early 20th century, was one of the first programmers of the Harvard Mark I computer. Americans have led the world in physics as well with the likes of Alan Harvey Guth, Steven Weinberg, and Sam Bard Treiman making important contributions to the field. Read on to learn more about the life and works of famous American scientists of the 20th century.
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1
Albert Einstein(One of the Greatest Physicists of All Time, Best Known for Developing the Theory of Relativity)
Birthdate: March 14, 1879
Sun Sign: Pisces
Birthplace: Ulm, Germany
Died: April 18, 1955
Deemed as the most influential physicist of the 20th century, the German-born physicist Albert Einstein was one of the greatest minds to have ever lived. Even his name is now synonymous with the term genius. The father of Modern Physics is credited with developing the theory of relativity and explaining the photoelectric effect. The latter won him the Nobel Prize.
Birthdate: October 5, 1958
Sun Sign: Libra
Birthplace: Manhattan, New York, United States
Public Welfare Medal-winning astrophysicist and academic Neil deGrasse Tyson hosted shows such as NOVA ScienceNow, Cosmos: A Spacetime Odyssey, and Star Talk. He is the director of Hayden Planetarium and contributed to the dismissal of Pluto’s status as the ninth planet. He has also written a monthly column as "Merlin.”
3
Carl Sagan(Astronomer and Planetary Scientist Best Known for His Scientific Contribution in Research on Extraterrestrial Life)
Birthdate: November 9, 1934
Sun Sign: Scorpio
Birthplace: Brooklyn, New York, United States
Died: December 20, 1996
Pulitzer- and Emmy-winning astrophysicist and author Carl Sagan was best known for co-writing the TV series Cosmos: A Personal Voyage. His novel Contact was adapted into a film. He was known for his extensive research on extra-terrestrial life, had taught at major universities, and written countless papers and science books.
4
J. Robert Oppenheimer(American Theoretical Physicist and Former Wartime Head of the ‘Los Alamos Laboratory’)
Birthdate: April 22, 1904
Sun Sign: Taurus
Birthplace: New York, New York, United States
Died: February 18, 1967
Hailed as a brilliant scientific mind, American physicist J Robert Oppenheimer, led the Manhattan Project which resulted in the development of atomic bomb during the World War II. The bombs were dropped on the Japanese cities of Hiroshima and Nagasaki in 1945. However, Oppenheimer was in a constant conflict over the moral issue of the weapons of mass destruction and rallied against nuclear proliferation.
5
Richard Feynman(One of the Joint Winners of Nobel Prize in Physics in 1965)
Birthdate: May 11, 1918
Sun Sign: Taurus
Birthplace: New York, New York, United States
Died: February 15, 1988
Theoretical physicist Richard Feynman won the Nobel Prize in Physics in 1965, along with Julian Schwinger and Shin'ichirō Tomonaga, for his research on quantum electrodynamics. He also contributed to the development of the atomic bomb. Feyman made it to Physics World’s list of the 10 greatest physicists of all time.
6
George Washington Carver(American Agricultural Scientist and Inventor Who Promoted Alternative Crops to Cotton and Methods to Prevent Soil Depletion)
Birthdate: 1864
Sun Sign: Capricorn
Birthplace: Diamond, Missouri, United States
Died: January 5, 1943
Agricultural scientist George Washington Carver is best remembered for promoting crops that were alternative to cotton, such as peanuts and sweet potatoes. He invented ways to prevent soil depletion and developed scores of products made from peanuts, including paints and cosmetics. He won numerous honors, such as the Spingarn Medal.
Birthdate: August 11, 1950
Sun Sign: Leo
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.
Birthdate: June 13, 1928
Sun Sign: Gemini
Birthplace: Bluefield, West Virginia, United States
Died: May 23, 2015
The inspiration behind the movie A Beautiful Mind, John F. Nash was a legendary mathematician whose work in the area of game theory earned him the Nobel Memorial Prize in Economic Sciences. In his later years, he was riddled with mental illness. He later died in a car crash.
9
John von Neumann(Great Mathematician Who Were Equally at Home in Pure and Applied Mathematics)
Birthdate: December 28, 1903
Sun Sign: Capricorn
Birthplace: Budapest, Hungary
Died: February 8, 1957
Hungarian-American scientist John von Neumann contributed to the development of game theory and the concept of self-replication. His work covered vast areas including math, economics, physics, and computer science. His research on nuclear physics led him to be part of the advisory committee of the U.S. Atomic Energy Commission.
10
Enrico Fermi(Italian Physicist, Nobel Laureate and Creator of the World's First Nuclear Reactor)
Birthdate: September 29, 1901
Sun Sign: Libra
Birthplace: Rome, Italy
Died: November 28, 1954
Italian physicist Enrico Fermi created the Chicago Pile-1, the world's first nuclear reactor. Known widely as the "architect of the atomic bomb," he was equally proficient in theoretical and experimental physics, and won the 1938 Nobel Prize in Physics for his work on radioactivity and for discovering transuranium elements.
11
Subrahmanyan Chandrasekhar(Astrophysicist Known for his 'Theoritical Studies of the Physical processes of importance to the Structure and Evolution of the Stars')
Birthdate: October 19, 1910
Sun Sign: Libra
Birthplace: Lahore, Pakistan
Died: August 21, 1995
Remembered for his varied contribution to astrophysics, Subrahmanyan Chandrasekhar is perhaps best known for his work on the evolution of massive stars. Today known as Chandrasekhar limit, it contributed to final understanding of supernovas, neutron stars, and black holes. A prolific writer, he also did significant work on energy transfer by radiation in stellar atmospheres and convection on solar surface.
Birthdate: May 27, 1907
Sun Sign: Gemini
Birthplace: Springdale
Died: April 14, 1964
Rachel Carson was a conservationist, marine biologist, and author. She is credited with authoring an influential book titled Silent Spring, which played a significant role in advancing the global environmental movement. Carson is also remembered for her book, The Sea Around Us, which earned her a U.S. National Book Award. She was posthumously honored with the Presidential Medal of Freedom.
13
Linus Pauling(One of the Greatest Scientists of All Time & Winner of Two Nobel Prizes)
Birthdate: February 28, 1901
Sun Sign: Pisces
Birthplace: Portland, Oregon, United States
Died: August 19, 1994
Only person to win two unshared Nobel Prizes, Linus Carl Pauling was an American theoretical physical chemist, who received the 1954 Nobel Prize in Chemistry for his work on nature of chemical bond and 1962 Nobel Prize for Peace for his efforts to stop nuclear weapon testing. Also a prolific writer and educator, he has published 1,200 books and papers.
14
Kurt Gödel(Mathematician, Philosopher and One of the Most Significant Logicians in History)
Birthdate: April 28, 1906
Sun Sign: Taurus
Birthplace: Brno, Czech Republic
Died: January 14, 1978
Hailed as one of the greatest logicians since Aristotle, Kurt Gödel was Austrian-born American mathematician, logician, and philosopher, who earned international stardom for his incompleteness theorem. Also credited with developing a technique called Gödel numbering, he later started working on Mathematical Platonism, a philosophical theory that failed to attract wide acceptance.
15
Claude Shannon(Mathematician, Engineer & Cryptographer Known as a 'Father of Information Theory')
Birthdate: April 30, 1916
Sun Sign: Taurus
Birthplace: Petoskey, Michigan, United States
Died: February 24, 2001
Claude Shannon was an electrical engineer, mathematician, and cryptographer. He is credited with publishing the article A Mathematical Theory of Communication which gave rise to the field of information theory. Hence, Shannon is considered the father of information theory. He is also credited with founding digital circuit design theory. During World War II, he contributed to the field of cryptanalysis.
16
Grace Hopper(Computer Scientist, Mathematician and One of the First Programmers of the ‘Harvard Mark I’ Computer)
Birthdate: December 9, 1906
Sun Sign: Sagittarius
Birthplace: New York, New York, United States
Died: January 1, 1992
Computer scientist and U.S. Navy rear admiral Grace Hopper was one of the first programmers of the Harvard Mark I computing system. She pioneered the machine-independent programming language technique, and the FLOW-MATIC language used by her was later used to create COBOL. She received a posthumous Presidential Medal of Freedom.
Birthdate: June 23, 1943
Sun Sign: Cancer
Birthplace: New Haven, Connecticut, United States
Birthdate: June 10, 1929
Sun Sign: Gemini
Birthplace: Birmingham, Alabama, U.S.
Died: December 26, 2021
E. O. Wilson is an American naturalist, biologist, and writer. An influential biologist, Wilson has earned several nicknames, such as The Darwin of the 21st century. He has also been referred to as the father of biodiversity and the father of sociobiology. In 1995, he was ranked among the most influential American personalities by Time magazine.
19
Nikola Tesla(Inventor, Engineer & Futurist, Who Obtained Over 300 Patents)
Birthdate: July 10, 1856
Sun Sign: Cancer
Birthplace: Smiljan, Croatia
Died: January 7, 1943
Inventor, engineer and futurist, Nikola Tesla, is best remembered for his contribution to the development of the modern alternating current (AC) electricity supply system. A prolific inventor, he had around 300 patents for his inventions. Even though he earned a considerable amount of money, he had poor money management skills and died a poor man.
20
Katherine Johnson(Mathematician and One of the First African-American Women to Work as a NASA Scientist)
Birthdate: August 26, 1918
Sun Sign: Virgo
Birthplace: White Sulphur Springs, West Virginia, United States
Died: February 24, 2020
Katherine Johnson was a physicist and mathematician, remembered as the first African-American female NASA scientist. Her calculations helped launch the space missions of Alan Shepard and John Glenn. She was crucial to the Apollo program and won a Congressional Gold Medal and a Presidential Medal of Freedom for her achievements.
21
Alexander Graham Bell(Inventor of Telephone & Co-Founder of 'American Telephone and Telegraph Company (AT&T)')
Birthdate: March 3, 1847
Sun Sign: Pisces
Birthplace: Edinburgh, Scotland
Died: August 2, 1922
Alexander Graham Bell was a scientist, inventor, and engineer. He is credited with inventing the first functional telephone. He is also credited with co-founding America's major telephone company AT&T, which has been going strong since 1885. Bell's later life was marked by his groundbreaking work in aeronautics, hydrofoils, and optical telecommunications. He was also an ardent supporter of compulsory sterilization.
22
Dennis Ritchie(American Computer Scientist Known for Creating the C Programming Language)
Birthdate: September 9, 1941
Sun Sign: Virgo
Birthplace: Bronxville, New York, United States
Died: October 12, 2011
Computer scientist, Dennis MacAlistair Ritchie, worked at Bell Labs Computing Sciences Research Center for most of his career, co-developing the Unix operating system and B programming language with Kenneth Thompson, co-winning the 1983 A.M. Turing Award for it. Earlier, he had also created C programming language and was involved with the development of the Plan 9 and Inferno operating systems.
23
Benoit Mandelbrot
(American Mathematician and Polymath Best Known for Popularizing the Concept of Fractal Geometry)
Birthdate: November 20, 1924
Sun Sign: Scorpio
Birthplace: Warsaw, Poland
Died: October 14, 2010
Noted mathematician and polymath, Benoit B. Mandelbrot is perhaps best known for his work on fractal. He not only coined the term, but also used computer-constructed images to illustrate the mathematical definition. Also credited with the discovery of Mandelbrot set and Mandelbrot law, he established that even those things which were apparently chaotic or rough had a "degree of order".
24
John McCarthy
(Mathematician, Computer scientist, Engineer, University teacher)
Birthdate: September 4, 1927
Sun Sign: Virgo
Birthplace: Boston
Died: October 24, 2011
25
Marvin Minsky
(Mathematician, Computer scientist, University teacher)
Birthdate: August 9, 1927
Sun Sign: Leo
Birthplace: New York City
Died: January 24, 2016
Birthdate: October 28, 1914
Sun Sign: Scorpio
Birthplace: New York City, New York, United States
Died: June 23, 1995
If the world is successful in its fight against polio, the credit goes to American virologist Jonas Salk who developed a vaccine for the disease. Described as a “miracle worker”, his concerns for humanity were reflected in the fact that he did not claim a patent for the vaccine. He founded the Salk Institute for Biological Studies, based in California.
27
Isaac Asimov(Writer Best Known for His Hard Science Fiction Novels and Professor of Biochemistry)
Birthdate: January 2, 1920
Sun Sign: Capricorn
Birthplace: Petrovichi, Russia
Died: April 6, 1992
Isaac Asimov was an American writer. Best known for his science fiction works, Asimov was regarded as one of the Big Three writers along with Arthur C. Clarke and Robert A. Heinlein. Asimov is credited with influencing most sci-fi writers since the 1950s. Nobel Prize winner Paul Krugman stated that one of Asimov's works inspired him to take up Economics.
28
Bennet Omalu(Forensic Pathologist Known for His Research in ‘Chronic Traumatic Encephalopathy’ in American Football Players)
Birthdate: September 30, 1968
Sun Sign: Libra
Birthplace: Idemili South, Nigeria
Nigerian-American physician, forensic-pathologist and neuropathologist Bennet Omalu is most-noted for discovering chronic traumatic encephalopathy (CTE) in American football players. He was serving at Allegheny County coroner's office in Pittsburgh at that time. He presently serves as President and Medical Director of Bennet Omalu Pathology, chief medical examiner for San Joaquin County, and as professor at the University of California, Davis.
Birthdate: February 4, 1943
Sun Sign: Aquarius
Birthplace: New Orleans, Louisiana, United States
Height: 6'8" (203 cm)
30
Terri Irwin(Naturalist Who is The Owner of Australia Zoo in 'Beerwah, Queensland')
Birthdate: July 20, 1964
Sun Sign: Cancer
Birthplace: Eugene, Oregon, United States
American–Australian naturalist Terri Irwin is best known as the co-host of The Crocodile Hunter, along with her husband, the late animal expert Steve Irwin. She has also been part of shows such as Croc Files and Crikey! It's the Irwins, and helped in the development of Australia Zoo.
31
Michio Kaku
(Theoretical Physicist and Author of the Best-Selling Books ‘Physics of the Impossible’ and ‘Physics of the Future')
Birthdate: January 24, 1947
Sun Sign: Aquarius
Birthplace: San Jose, California, United States
Apart from teaching at the City College of New York, theoretical physicist Michio Kaku also often pens his thoughts in blogs and has written several bestselling books, such as The God Equation. His research is focused on the string theory. He also believes in the existence of aliens.
32
Dorothy Vaughan
(American Mathematician, Human Computer and the First African-American to Receive Promotion as Supervisor in NASA)
Birthdate: September 20, 1910
Sun Sign: Virgo
Birthplace: Kansas City, Missouri, United States
Died: November 10, 2008
American mathematician Dorothy Vaughan was also known as a "human computer." Initially a math teacher, she became the first African-American supervisor of NACA, later part of NASA, at a time when racial segregation was rampant in the U.S. Her contribution to the early American space programs is invaluable.
33
Cecilia Payne-Gaposchkin
(American Astronomer and Astrophysicist)
Birthdate: May 10, 1900
Sun Sign: Taurus
Birthplace: Wendover, Buckinghamshire, England
Died: December 7, 1979
After losing her father at 4, Cecilia Payne-Gaposchkin was raised singlehandedly by her mother. The incredibly talented Cecilia studied at Cambridge but failed to secure a degree because of her gender. She later joined Harvard and opposing prevalent beliefs, proposed that stars were mainly made of hydrogen and helium.
34
Mary Jackson
(Mathematician)
Birthdate: April 9, 1921
Sun Sign: Aries
Birthplace: Hampton, Virginia, United States
Died: February 11, 2005
American mathematician and aerospace engineer Mary Jackson went down in history as the first African-American woman to work as a NASA engineer. Initially a math teacher, she later joined NACA under Dorothy Vaughan and contributed to countless American space programs at a time when racial segregation was the norm.
35
Sally Ride(The First American Woman and The Third Woman in Space)
Birthdate: May 26, 1951
Sun Sign: Gemini
Birthplace: Encino, Los Angeles, California, United States
Died: July 23, 2012
Astronaut and physicist Sally Ride was the first American woman and the youngest American astronaut to enter space. Following her death, it was revealed that she had been in a 27-year lesbian relationship with tennis player and professor Tam O'Shaughnessy. Sally herself was a ranked junior tennis player, too.
36
Vera Rubin
(American Astronomer Known for Her Pioneering Work on Galaxy Rotation Rates)
Birthdate: July 23, 1928
Sun Sign: Leo
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.
Birthdate: April 9, 1928
Sun Sign: Aries
Birthplace: New York, Manhattan
While he grew up to be a Harvard math professor, that didn’t stop Tom Lehrer from pursuing his childhood love for music. He gained fame as a satirical composer, with songs such as So Long, Mom, I’m Off to Drop the Bomb and That Was The Year That Was.
38
Har Gobind Khorana(Indian American Biochemist Who was One of the Recipients of the 1968 Nobel Prize in Medicine)
Birthdate: January 9, 1922
Sun Sign: Capricorn
Birthplace: Punjab, India
Died: November 9, 2011
Born into a poor family in British India, Har Gobind Khorana studied on scholarships and later bagged a seat at the University of Liverpool and thus moved to England. The renowned biochemist ended up winning the Nobel Prize for his research on how nucleotides in nucleic acids control protein synthesis.
39
James Watson(Molecular Biologist Who Co-discovered the Double Helix Structure of DNA With Francis Crick)
Birthdate: April 6, 1928
Sun Sign: Aries
Birthplace: Chicago, Illinois, United States
James Watson is a geneticist, molecular biologist, and zoologist. He is credited with co-authoring the academic paper that propounded the double helix structure of nucleic acids such as DNA for which he was awarded the Nobel Prize in 1962. In 1977, he was honored with the Presidential Medal of Freedom. In 1997, he was awarded the National Medal of Science.
40
Clyde Tombaugh
(Astronomer, University teacher)
Birthdate: February 4, 1906
Sun Sign: Aquarius
Birthplace: Streator
Died: January 17, 1997
Though he wasn’t formally educated in astronomy, Clyde Tombaugh was immensely interested in the subject since childhood and had built his own telescope after high school. He grew up to discover Pluto, then regarded as the ninth planet but later declared a "dwarf planet," and many other celestial bodies.
Birthdate: August 29, 1947
Sun Sign: Virgo
Birthplace: Boston, Massachusetts, United States
Temple Grandin is an American activist and scientist. An outspoken proponent of the neurodiversity and autism rights movements, Grandin is one of the first individuals to document the insights gained from her own experience of autism. She has also authored over 60 scientific papers on animal behavior. Her life and work inspired the 2010 biographical drama film Temple Grandin.
42
Norman Borlaug(American Agronomist and Winner of the Nobel Prize for Peace in 1970)
Birthdate: March 25, 1914
Sun Sign: Aries
Birthplace: Cresco, Iowa, United States
Died: September 12, 2009
Norman Borlaug was an American agronomist who played a key role in the Green Revolution, a set of research technology transfer initiatives that increased agricultural production, for which he won the Nobel Peace Prize in 1970. Nicknamed the Father of the Green Revolution, Borlaug was also honored with the Congressional Gold Medal and Presidential Medal of Freedom for his work.
Birthdate: September 15, 1929
Sun Sign: Virgo
Birthplace: Manhattan, New York City, U.S.
Died: May 24, 2019
Nobel Prize-winning American physicist Murray Gell-Mann is best remembered for his research on elementary particles. The Yale and MIT alumnus later taught at Caltech and is credited with coining the terms "quark" and "strangeness" in quantum physics. A linguistic enthusiast, he also co-established the Evolution of Human Languages program.
Birthdate: April 19, 1912
Sun Sign: Aries
Birthplace: Ishpeming, Michigan
Died: February 25, 1999
Glenn T. Seaborg was an American chemist who shared the 1951 Nobel Prize in Chemistry with Edwin McMillan for discovering the first transuranium elements. He also authored or co-authored several books and articles, including 500 scientific journals. In 2005, Glenn T. Seaborg was inducted posthumously into the National Inventors Hall of Fame.
Birthdate: March 5, 1938
Sun Sign: Pisces
Birthplace: Chicago
Died: November 22, 2011
Lynn Margulis was an evolutionary theorist, biologist, educator, and science author. She was a modern proponent of the significance of symbiosis in evolution. Along with British chemist James Lovelock, Margulis was the co-developer of the Gaia hypothesis. She was a strong critic of neo-Darwinism. In 2001, she was honored with the Golden Plate Award of the American Academy of Achievement.
Birthdate: May 17, 1940
Sun Sign: Taurus
Birthplace: Springfield, Massachusetts
Birthdate: February 26, 1852
Sun Sign: Pisces
Birthplace: Tyrone Township, Michigan, United States
Died: December 14, 1943
Physician, nutritionist, and businessman John Harvey Kellogg served as the director of the Battle Creek Sanitarium, which was a combination of a European spa, a hydrotherapy center, a hospital, and a hotel. He believed in biologic living. However, he is best remembered as the inventor of corn flakes.
48
Ronald McNair
(Physicist, Astronaut)
Birthdate: October 21, 1950
Sun Sign: Libra
Birthplace: Lake City
Died: January 28, 1986
A doctorate in physics from MIT Cambridge, Ronald McNair worked on chemical lasers before joining NASA and in 1984 flew as a mission specialist on STS-41-B aboard Challenger, becoming the second African-American to do so. In January 1986, he was selected to fly on STS-51-L, but was killed along with rest of the crews when Challenger disintegrated soon after liftoff.
Birthdate: January 15, 1908
Sun Sign: Capricorn
Birthplace: Budapest, Hungary
Died: September 9, 2003
Edward Teller was one of the famous "Martians,” or eminent Hungarian scientists who had migrated to the U.S. A prominent chemical engineer and nuclear physicist, he was part of the team that created the world’s first atomic bomb and also designed the first hydrogen bomb, or thermonuclear bomb.
50
Margaret Hamilton
(American Computer Scientist, Systems Engineer, and Business Owner)
Birthdate: August 17, 1936
Sun Sign: Leo
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.