2 Neil deGrasse Tyson(Astrophysicist)
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, Astrophysicist)
4 Richard Feynman(Physicist)
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.
5 Steve Wozniak(Co-Founder of Apple Inc.)
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.
6 J. Robert Oppenheimer(Theoretical physicist)
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.
7 George Washington Carver(Agricultural scientist)
8 John Forbes Nash Jr.(Mathematician)
9 John von Neumann(Great Mathematician Who Were Equally at Home in Pure and Applied Mathematics)
10 Subrahmanyan Chandrasekhar(Astrophysicist Known for his 'Theoritical Studies of the Physical processes of importance to the Structure and Evolution of the Stars')
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.
11 Claude Shannon(Known as a "Father of Information Theory")
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.
12 Rachel Carson(Marine biologist)
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 Kurt Gödel(Logician, Mathematician, Philosopher)
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.
14 Linus Pauling(Chemist, Biochemist)
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.
15 Grace Hopper(Computer Scientist)
16 Vint Cerf(Computer scientist)
17 E. O. Wilson(Biologist)
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.
18 Nikola Tesla(Inventor, Engineer & Futurist, Who Obtained Over 300 Patents)
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.
19 Andrew Wiles(Mathematician, University teacher)
English mathematician Sir Andrew John Wiles, a Royal Society Research Professor at the University of Oxford, is best known for proving the modularity theorem for semistable elliptic curves, thereby proving Fermat's Last Theorem for which he was awarded the Abel Prize and the Copley Medal by the Royal Society. He also proved the main conjecture of Iwasawa theory.
20 Benoit Mandelbrot(Mathematician and polymath)
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".
21 Katherine Johnson(Mathematician)
22 Terri Irwin(Naturalist Who is The Owner of Australia Zoo in 'Beerwah, Queensland')
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.
23 Wernher Von Braun(One of the Greatest Rocket Developers and Space Exploration in the 20th Century)
German-born American aerospace engineer and space architect, Wernher Von Braun, worked in Nazi Germany's rocket development program as a young man. After World War II, he moved to the United States where he became a pioneer of rocket and space technology in the nation. In his later career, he became director of the newly formed Marshall Space Flight Center.
24 Bennet Omalu(Pathologist, Neuropathologist)
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.
25 Jonas Salk(Medical researcher)
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.
26 Ken Thompson(Computer Scientist)
27 Lynn Margulis(Author)
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.
28 Mary Jackson(Mathematician)
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.
29 Vera Rubin(Astronomer)
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.
30 Cecilia Payne-Gaposchkin(Astronomer, Astrophysicist)
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.
31 Dennis Ritchie(Computer Scientist)
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.
32 Temple Grandin(Scientist)
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.
33 John McCarthy(Mathematician, Computer scientist, Engineer, University teacher)
34 Michio Kaku(Physicist who wrote the best-selling books Physics of the Impossible)
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.
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.
36 Tom Lehrer(American musician)
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.
37 Sam Harris(Philosopher, Author)
One of the "Four Horsemen of Atheism," neuroscientist and author Sam Harris is known for his works on topics such as religion, artificial intelligence, and terrorism. His books include the New York Times bestseller The End of Faith. He hosted the podcast Making Sense and released a meditation app, too.
38 Dorothy Vaughan(Mathematician)
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.
39 Terence McKenna(Ethnobotanist)
40 James Watson(Molecular Biologist Who Co-discovered the Double Helix Structure of DNA With Francis Crick)
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.
41 Glenn T. Seaborg(Chemist)
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.
42 Norman Borlaug(Agronomist)
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.
43 John Harvey Kellogg(Doctor, Inventor)
44 Clyde Tombaugh(Astronomer, University teacher)
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.
45 Murray Gell-Mann(Physicist)
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.
46 Ronald McNair(Physicist, Astronaut)
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.
47 John G. Trump(Scientist)
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.
48 Alan Kay(Computer Scientist)
49 Jennifer Doudna(Biochemist)
American biochemist Jennifer Doudna of the University of California, Berkeley, who has made fundamental contributions in biochemistry and genetics, is best-known for her pioneering work in CRISPR gene-editing. Doudna and Emmanuelle Charpentier received the 2020 Nobel Prize in Chemistry for developing a method for genome editing through CRISPR, marking them as the only two women to share science Nobel ever.