Famous 20th Century Astronomers

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 1 
Neil deGrasse Tyson
(American Astrophysicist, Planetary Scientist and Science Communicator)
Neil deGrasse Tyson
23
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.”

 2 
Carl Sagan
(Astronomer and Planetary Scientist Best Known for His Scientific Contribution in Research on Extraterrestrial Life)
Carl Sagan
13
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.
 3 
Cecilia Payne-Gaposchkin
(American Astronomer and Astrophysicist)
Cecilia Payne-Gaposchkin
9
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. 

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 4 
Clyde Tombaugh
(Astronomer, University teacher)
Clyde Tombaugh
8
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.

 5 
Stephen Hawking
(Theoretical Physicist - First to Set Out a Theory of Cosmology)
Stephen Hawking
23
Birthdate: January 8, 1942
Sun Sign: Capricorn
Birthplace: Oxford, England
Died: March 14, 2018

Stephen Hawking was an English theoretical physicist and cosmologist, who despite being afflicted motor neurone disease that severely limited his physical abilities, was able to build a phenomenally successful career. He was the first to set out a theory of cosmology explained by a union of the general theory of relativity and quantum mechanics. Hawking was ranked 25 in the BBC's poll of the 100 Greatest Britons, in 2002.

 6 
Fritz Zwicky
(Swiss Astronomer Known For His Inference and Existence of Unseen 'Dark Matter' using Virial Theorem)
Fritz Zwicky
4
Birthdate: February 14, 1898
Sun Sign: Aquarius
Birthplace: Varna, Bulgaria
Died: February 8, 1974

Born to a businessman and diplomat father in Bulgaria, Fritz Zwicky was initially sent to Switzerland to study commerce but ended up deviating to math and physics. He then moved to the U.S. to work with Caltech and gained fame for his research on what he called the supernova.

 7 
Gerard Kuiper
(Dutch Astronomer, Planetary Scientist, Selenographer, Author and Professor)
Gerard Kuiper
3
Birthdate: December 7, 1905
Sun Sign: Sagittarius
Birthplace: Tuitjenhorn, Netherlands
Died: December 23, 1973

Gerard Kuiper was blessed with an unusually sharp eyesight and could see stars clearly with the naked eye. The Dutch-born scientist later moved to the U.S., where he established the University of Arizona’s LPL. He also initiated research on the belt of comets surrounding the Sun, known as the Kuiper belt.

 8 
Harlow Shapley
(American Scientist and Political Activist)
Harlow Shapley
3
Birthdate: November 2, 1885
Sun Sign: Scorpio
Birthplace: Nashville, Missouri, United States
Died: October 20, 1972

American scientist Harlow Shapley is best-remembered for ascertaining correct position of Sun within Milky Way Galaxy and for heading the Harvard College Observatory. He determined the size and shape of the Milky Way Galaxy and the Sun’s position within it using the Cepheid variable stars and wrote the Liquid Water Belt that provided scientific acceptance to Hubertus Strughold’s ecosphere theory.

 9 
J. Allen Hynek
(Astronomer, Ufologist)
J. Allen Hynek
4
Birthdate: May 1, 1910
Sun Sign: Taurus
Birthplace: Chicago
Died: April 27, 1986

When the American government, baffled by unexplained sightings of flying objects, assigned J. Allen Hynek the task of solving the mystery, Hynek was sceptical. However, he later became the first person to scientifically analyze such sightings. He also established the "Close Encounter" classification system to study UFOs.

 10 
Walter Lewin
(Astronomer, University teacher, Astrophysicist, Physicist)
Walter Lewin
7
Birthdate: January 29, 1936
Sun Sign: Aquarius
Birthplace: The Hague
 11 
Vera Rubin
(American Astronomer Known for Her Pioneering Work on Galaxy Rotation Rates)
Vera Rubin
6
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.

 12 
James Glaisher
(Meteorologists)
James Glaisher
4
Birthdate: April 7, 1809
Sun Sign: Aries
Birthplace: Rotherhithe, London, England
Died: February 7, 1903

Renowned meteorologist and aeronaut James Glaisher was a pioneer of balloon flights and had penned the iconic book Travels in the Air. He had also contributed to the formation of the Meteorological Society and the Aeronautical Society of Britain. The 2019 movie The Aeronauts depicts his exploits as a balloonist.

 13 
Fred Hoyle
(English Astronomer Who Formulated the Theory of 'Stellar Nucleosynthesis')
Fred Hoyle
4
Birthdate: June 24, 1915
Sun Sign: Cancer
Birthplace: Bingley, England
Died: August 20, 2001

Fred Hoyle was an English astronomer known for his theory of stellar nucleosynthesis. He spent most of his career at the Institute of Astronomy at Cambridge, serving as its director for six years. He was also an author of science fiction novels, short stories, and plays and appeared in a series of radio talks on astronomy for the BBC.  

 14 
Henrietta Swan Leavitt
4
Birthdate: July 4, 1868
Sun Sign: Cancer
Birthplace: Lancaster, Massachusetts
Died: December 12, 1921

Born to a church minister, Henrietta Swan Leavitt grew up to work as a “human computer” at the Harvard Observatory. The American astronomer gained fame for discovering the period-luminosity relation of Cepheid variables. However, her brilliant scientific career was halted by her death due to stomach cancer at 53.

 15 
Jocelyn Bell Burnell
(British Astrophysicist Who Discovered the First Radio Pulsars)
Jocelyn Bell Burnell
5
Birthdate: July 15, 1943
Sun Sign: Cancer
Birthplace: Lurgan, Northern Ireland

Jocelyn Bell Burnell is an astrophysicist from Northern Ireland. As a postgraduate student, she discovered the first radio pulsars. She graduated from the University of Glasgow and pursued an academic career. In 2018, she received the Special Breakthrough Prize in Fundamental Physics for her discovery of radio pulsars. She donated the three million dollars she received as prize money.  

 16 
Eugene Merle Shoemaker
(American Geologist Best Known for Co-Discovering the 'Comet Shoemaker-Levy 9')
Eugene Merle Shoemaker
3
Birthdate: April 28, 1928
Sun Sign: Taurus
Birthplace: Los Angeles, California, United States
Died: July 18, 1997

Best known for discovering the Shoemaker-Levy 9 comet, with his wife, Carolyn, and David H. Levy, Eugene Merle Shoemaker was an American astrogeologist who had also worked with the U.S. Geological Survey. He had been part of NASA’s lunar exploration missions. Following his death, his ashes were transported to the Moon.

 17 
Karl Schwarzschild
(German Physicist and Astronomer)
Karl Schwarzschild
3
Birthdate: October 9, 1873
Sun Sign: Libra
Birthplace: Frankfurt, Germany
Died: May 11, 1916

Karl Schwarzschild was a German astronomer and physicist. He is remembered for his contributions to the general theory of relativity; Schwarzschild came up with the first exact solution to the Albert Einstein field equations. He also contributed immensely to the theory of black holes.

 18 
Williamina Fleming
(Scottish Astronomer Famous for Her Discovery of the 'Horsehead Nebula')
Williamina Fleming
3
Birthdate: May 15, 1857
Sun Sign: Taurus
Birthplace: Dundee, Scotland
Died: May 21, 1911

Born in Scotland, Williamina Fleming moved to the U.S. with her husband, where she began working as a housekeeper for Harvard Observatory director Edward C. Pickering. Pickering secured her a job at the observatory, and Fleming went on to establish a classification and cataloguing system for stars.

 19 
Max Tegmark
(Physicist, Astronomer, Astrophysicist)
Max Tegmark
5
Birthdate: May 5, 1967
Sun Sign: Taurus
Birthplace: Sweden

Born to math professor Harold S. Shapiro, Max Tegmark grew up to co-establish the Future of Life Institute, with funding from Elon Musk. The MIT professor is a specialist in cosmology, physics, and machine learning and had also penned a book on artificial intelligence, titled Life 3.0.

 20 
Michael E. Brown
(Astronomer)
Michael E. Brown
5
Birthdate: June 5, 1965
Sun Sign: Gemini
Birthplace: Huntsville
Princeton and UCB alumnus and Caltech professor Michael E. Brown is credited with discovering many "dwarf planets" and was the man behind Pluto’s demotion from a planet to a "dwarf planet." Named to Wired Online's 2006 list of the Top Ten Sexiest Geeks, he has also authored a bestselling memoir.
 21 
Milutin Milanković
(Serbian Climatologist Who Gave the Explanation of Earth's Climate Changes, Which Partly Explained the Ice Ages)
Milutin Milanković
3
Birthdate: May 28, 1879
Sun Sign: Gemini
Birthplace: Dalj, Croatia
Died: December 12, 1958

Milutin Milanković was a Serbian astronomer, mathematician, geophysicist, climatologist, and civil engineer. He is best remembered for his explanation of Earth's climate changes, which partly explained the ice ages. Milutin Milankovitch's biography inspired a 2007 documentary film titled A Traveler Through Distant Worlds and Times.

 22 
Lawrence M. Krauss
(Astronomer, Physicist, Astrophysicist, Academic, Non-fiction writer, University teacher, Theoretical physicist)
Lawrence M. Krauss
5
Birthdate: May 27, 1954
Sun Sign: Gemini
Birthplace: New York City

American-Canadian theoretical physicist Lawrence M. Krauss has taught at institutes such as ASU and Yale and also penned several bestselling books. Known for his research on dark energy and zero-energy states, he was later accused of sexual misconduct and thus lost the directorship of the ASU’s Origins Project.

 23 
George Ellery Hale
(American Astronomer and Journalist)
George Ellery Hale
3
Birthdate: June 29, 1868
Sun Sign: Cancer
Birthplace: Chicago, Illinois, United States
Died: February 21, 1938

George Ellery Hale was an American solar astronomer. He discovered magnetic fields in sunspots, a discovery that gained him international fame. He played key roles in the planning or construction of several world-leading telescopes, including the 40-inch refracting telescope at Yerkes Observatory. He was a major figure in the foundation of the International Union for Cooperation in Solar Research. 

 

 24 
Robert Woodrow Wilson
(Physicist, Astronomer)
Robert Woodrow Wilson
4
Birthdate: January 10, 1936
Sun Sign: Capricorn
Birthplace: Houston, Texas, United States
 25 
Samuel Langley
(American Aviation Pioneer, Astronomer and Physicist Known for Inventing 'Bolometer')
Samuel Langley
2
Birthdate: August 22, 1834
Sun Sign: Leo
Birthplace: Roxbury, Boston, Massachusetts, United States
Died: February 27, 1906

Astrophysicist Samuel Pierpont Langley had worked as an engineer before he taught physics and astronomy at the Western University of Pennsylvania. He later took over as the director of the Allegheny Observatory. He is best remembered for his research on solar radiation and for inventing the bolometer.

 26 
Jayant Narlikar
(Physicist, Astronomer, Astrophysicist, Scientist, University teacher, Science fiction writer)
Jayant Narlikar
7
Birthdate: July 19, 1938
Sun Sign: Cancer
Birthplace: Kolhapur

Born to a math professor father and a Sanskrit scholar mother, Astrophysicist and IUCAA professor Jayant Narlikar grew up to collaborate with Sir Fred Hoyle, leading to the conformal gravity theory, also known as the Hoyle-Narlikar theory. He has won the Padma Bhushan and Padma Vibhushan and penned sci-fi novels, too.

 27 
Jan Oort
(Dutch Astronomer)
Jan Oort
3
Birthdate: April 28, 1900
Sun Sign: Taurus
Birthplace: Franeker, Netherlands
Died: November 5, 1992

Jan Oort was a Dutch astronomer whose ground-breaking discoveries revolutionized astronomy. Widely regarded as one of the 20th century's greatest astronomers, Jan Oort's work helped understand the Milky Way. He also pioneered radio astronomy and was honored with several prestigious awards like the Bruce Medal, Gold Medal of the Royal Astronomical Society, Janssen Medal, and Prix Jules Janssen.

 28 
Antony Hewish
(Radio Astronomer)
Antony Hewish
4
Birthdate: May 11, 1924
Sun Sign: Taurus
Birthplace: Fowey, Cornwall, England
Died: September 13, 2021

Radio astronomer and physicist Antony Hewish is best known for his Nobel Prize-winning research on pulsars. Apart from teaching at Cavendish Laboratory, Cambridge, he has also served as an advisory council member for the Campaign for Science and Engineering. He also has six honorary degrees to his credit.       

 29 
Giovanni Schiaparelli
(Italian Astronomer and Science Historian)
Giovanni Schiaparelli
3
Birthdate: March 14, 1835
Sun Sign: Pisces
Birthplace: Savigliano, Italy
Died: July 4, 1910

Giovanni Schiaparelli made headlines when he discovered the canals of Mars, suggesting the existence of intelligent life forms on the planet. He also discovered the asteroid named Hesperia and was associated with the Brera Observatory in Milan for more than 40 years. He had also been a senator of Italy.

 30 
Milan Rastislav Štefánik
(One of the Founding Fathers of Czechoslovakia)
Milan Rastislav Štefánik
3
Birthdate: July 21, 1880
Sun Sign: Cancer
Birthplace: Košariská, Slovakia
Died: May 4, 1919

Milan Rastislav Štefánik was a Slovak politician, diplomat, aviator, and Freemason. He served as the minister of war for Czechoslovakia during World War I while simultaneously serving as a general in the French Army. He was a  leading member of the Czechoslovak National Council and contributed to the cause of Czechoslovakian sovereignty. He died in a plane crash in 1919.  

 31 
Brian Schmidt
(Vice-Chancellor of the Australian National University (ANU))
Brian Schmidt
4
Birthdate: February 24, 1967
Sun Sign: Pisces
Birthplace: Missoula, Montana, United States

Nobel Prize-winning astronomer Brian Schmidt is best known for discovering what is known as dark energy of the universe. Born in the US, the Harvard alumnus later moved to Australia for his work. He has taught at the Australian National University and is now the university’s vice chancellor.

 32 
George Darwin
(British Barrister, Astronomer and the Second Son of Naturalist Charles Darwin)
George Darwin
4
Birthdate: July 9, 1845
Sun Sign: Cancer
Birthplace: Down House, Downe, Kent, England
Died: December 7, 1912

Born to legendary biologist Charles Darwin, George Darwin initially studied law and became a barrister. However, his interest in science made him deviate to astronomy. He believed the Moon was one part of the Earth. He later also taught at Cambridge and was made a Fellow of The Royal Society.

 33 
Karl Gordon Henize
(Astronomer, Astronaut, Scientist)
Karl Gordon Henize
3
Birthdate: October 17, 1926
Sun Sign: Libra
Birthplace: Cincinnati
Died: October 5, 1993

Karl Gordon Henize was a space scientist and astronaut who authored seventy papers on astronomy. He was posted at various observatories round the world. Later on, he joined NASA as scientist-astronaut and flew on space shuttle Challenger as a mission specialist.

 34 
Camille Flammarion
(French Astronomer and Author)
Camille Flammarion
3
Birthdate: February 26, 1842
Sun Sign: Pisces
Birthplace: Val-de-Meuse, France
Died: June 3, 1925

French astronomer Camille Flammarion began his career as a human computer at the Paris Observatory at 16. He believed intelligent beings from Mars had tried to communicate with people on Earth in the past. He also published L'Astronomie and penned sci-fi novels such as Omega: The Last Days of the World.

 35 
Eric W. Weisstein
(Mathematician, Astronomer, Non-fiction writer)
Eric W. Weisstein
3
Birthdate: March 18, 1969
Sun Sign: Pisces
Birthplace: Bloomington

Famous for creating and maintaining MathWorld, the most widely accessed internet site for mathematical resources, Eric W. Weisstein is an encyclopedist who began compiling scientific encyclopedias as a high school student. Author of the bestselling book, CRC Concise Encyclopedia of Mathematics, he is also credited with creating ScienceWorld website.

 36 
Peter Naur
(Danish Astronomer)
Peter Naur
3
Birthdate: October 25, 1928
Sun Sign: Scorpio
Birthplace: Frederiksberg, Denmark
Died: January 3, 2016

Peter Naur was a Danish computer science pioneer. Along with John Backus, he contributed to the development of the Backus–Naur Form (BNF) notation used in describing the syntax for most programming languages. He began his career as an astronomer, eventually shifting to computers. He was a professor of computer science at the University of Copenhagen for many years. 

 37 
Carolyn S. Shoemaker
(American Astronomer and a Co-discoverer of Comet Shoemaker–Levy 9)
Carolyn S. Shoemaker
3
Birthdate: June 24, 1929
Sun Sign: Cancer
Birthplace: Gallup, New Mexico, United States
Died: August 13, 2021

Carolyn S. Shoemaker is an American astronomer best known as a co-discoverer of Comet Shoemaker-Levy 9. A prolific discoverer of comets, she once held the record for most comets discovered by an individual. She was married to geologist Eugene Shoemaker and often collaborated with him. The couple was awarded the James Craig Watson Medal in 1998. 

 38 
Geoffrey Marcy
(Astronomer, Physicist, University teacher)
Geoffrey Marcy
4
Birthdate: September 29, 1954
Sun Sign: Libra
Birthplace: St. Clair Shores

American astronomer Geoffrey Marcy is best known for his use of Doppler shifts in discovering many extrasolar planets, which paved way for discovery of several hundred planetary bodies in multiple star systems. Seventy of the first hundred known exoplanets were discovered by Marcy and his research teams, who also detected the first planetary system around a Sun-like star, Upsilon Andromedae

 39 
Lyman Spitzer
(Astronomer, Astrophysicist, Physicist, University teacher)
Lyman Spitzer
3
Birthdate: June 26, 1914
Sun Sign: Cancer
Birthplace: Toledo
Died: March 31, 1997

Lyman Spitzer was an American theoretical physicist, mountaineer, and astronomer. He was known for his research into star formation and plasma physics. He is credited with the invention of the stellarator plasma device and he was the one who first conceived the idea of telescopes operating in outer space. He was a founding member of the World Cultural Council. 

 40 
Laura Mersini-Houghton
(Albanian-American Cosmologist and Theoretical Physicist)
Laura Mersini-Houghton
4
Birthplace: Tirana, Albania
 41 
Gerard K. O'Neill
(American Physicist and Space Activist Known for Inventing the 'Particle Storage Ring')
Gerard K. O'Neill
3
Birthdate: February 6, 1927
Sun Sign: Aquarius
Birthplace: Brooklyn, New York, United States
Died: April 27, 1992

American physicist and space activist Gerard K. O'Neill is noted for inventing the particle storage ring for high-energy physics experiments and for proposing and advocating colonization of space. He proposed the space settlement concept O'Neill cylinder in his award-winning book The High Frontier: Human Colonies in Space, invented a magnetic launcher called mass driver and founded the Space Studies Institute.

 42 
Karl Guthe Jansky
(American Physicist, Radio Engineer and One of the Founding Figures of 'Radio Astronomy')
Karl Guthe Jansky
3
Birthdate: October 22, 1905
Sun Sign: Libra
Birthplace: Norman, Oklahoma, United States
Died: February 14, 1950

Karl Guthe Jansky was an American physicist and radio engineer. He first discovered radio waves emanating from the Milky Way in August 1931. However, due to his lack of formal training as an astronomer, research into radio astronomy remained dormant for many years. Later on, he came to be widely regarded as one of the founding figures of radio astronomy. 

 43 
Margaret Burbidge
(British-American Observational Astronomer and Astrophysicist Known for Her Contributions to the Theory of ‘Quasars')
Margaret Burbidge
3
Birthdate: August 12, 1919
Sun Sign: Leo
Birthplace: Davenport, Stockport, England
Died: April 5, 2020

Margaret Burbidge was a British-American observational astronomer and astrophysicist. She was the first author of the influential B2FH paper and one of the founders of stellar nucleosynthesis. She held several leadership and administrative posts and was well known for her work opposing discrimination against women in astronomy. In 1988, she was awarded the Albert Einstein World Award of Science. 

 44 
Bernard Lovell
(British Physicist and Radio Astronomer Known for Developing the 76m Radio Telescope at Jodrell Bank)
Bernard Lovell
4
Birthdate: August 31, 1913
Sun Sign: Virgo
Birthplace: Oldland Common, Bristol, England
Died: August 6, 2012

Bernard Lovell was a British physicist and radio astronomer who served as the first director of Jodrell Bank Observatory, holding this position from 1945 to 1980. He studied at the University of Bristol and embarked on an academic career. During World War II, he worked for the Telecommunications Research Establishment (TRE). He was awarded the Benjamin Franklin Medal in 1980. 

 45 
Riccardo Giacconi
(Astrophysicist)
Riccardo Giacconi
3
Birthdate: October 6, 1931
Sun Sign: Libra
Birthplace: Genoa
Nobel Prize-winning physicist Riccardo Giacconi was a pioneer in the field of X-ray astronomy. Born in Italy, he later went to the U.S. to pursue his research as a Fulbright scholar. He was the man behind the launch of the Einstein Observatory and the Chandra X-ray Observatory.
 46 
Ralph H. Fowler
(Physicist, Astronomer)
Ralph H. Fowler
2
Birthdate: January 17, 1889
Sun Sign: Capricorn
Birthplace: Roydon, Essex, England, United Kingdom
Died: July 28, 1944
 47 
Venetia Phair
(Amateur astronomer)
Venetia Phair
4
Birthdate: July 11, 1918
Sun Sign: Cancer
Birthplace: Oxford, England
Died: April 30, 2009
 48 
James Jeans
(British Physicist, Astronomer and Mathematician)
James Jeans
2
Birthdate: September 11, 1877
Sun Sign: Virgo
Birthplace: Ormskirk, Lancashire, England
Died: September 16, 1946

James Jeans was an English physicist, astronomer, and mathematician who made great contributions to the areas of quantum theory, the theory of radiation, and stellar evolution. Along with Arthur Eddington, Jeans is a founder of British cosmology. He spent his academic career at Trinity College, Cambridge, and the Princeton University. He received the Royal Medal in 1919. 

 49 
Seth Shostak
(Astronomer, Radio personality)
Seth Shostak
4
Birthdate: July 20, 1943
Sun Sign: Cancer
Birthplace: Mountain View

Best known as a senior astronomer of the SETI Institute, Seth Shostak has also been seen on the radio show Big Picture Science. He has also appeared as himself or as an astronomer in numerous films and TV series such as The Day the Earth Stood Still and Alien Encounters.

 50 
David H. Levy
(Canadian Amateur Astronomer Who Co-discovered Comet Shoemaker–Levy 9)
David H. Levy
3
Birthdate: May 22, 1948
Sun Sign: Gemini
Birthplace: Montreal, Canada

Although he studied English literature and eventually gained a master’s degree in the subject, David H. Levy was an avid comet watcher since childhood. He later teamed up with Gene and Carolyn Shoemaker to discover over 20 comets. A skilled science writer, too, he penned books such as Skywatching.