CARL SAGAN Biography - Famous Scientists


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Carl Edward Sagan (November 9, 1934 December 20, 1996) was an American                     
astronomer and science popularizer. He pioneered exobiology and promoted the               
Search for ExtraTerrestrial Intelligence (SETI). He is world-famous for his                 
popular science books and the television series Cosmos, which he co-wrote and               
presented. In his works he frequently advocated the scientific method.                     
Carl Sagan was born in Brooklyn, New York. His father, Sam Sagan, was a Jewish             
garment worker and his mother, Rachel Molly Gruber, was a housewife. Sagan                 
attended the University of Chicago, where he received a bachelor's degree (1955)           
and a master's degree (1956) in physics, before earning his doctorate (1960) in             
astronomy and astrophysics. He taught at Harvard University until 1968, when he             
moved to Cornell University.                                                               
Sagan became a full professor at Cornell in 1971 and directed a lab there. He               
contributed to most of the unmanned space missions that explored our solar                 
system. He conceived the idea of adding an unalterable and universal message on             
spacecraft destined to leave the solar system, that could be understood by any             
extraterrestrial intelligence that might find it. The first message that was               
actually sent into space was a gold-anodized plaque attached to the space probe             
Pioneer 10. He continued to refine his designs and the most elaborate such                 
message he helped to develop was the Voyager Golden Record that was sent out               
with the Voyager space probes.                                                             
Sagan was among the first to hypothesize that Titan and Jupiter's moon Europa               
may possess oceans (a subsurface ocean in the case of Europa) or lakes. Thus               
making the hypothesized water ocean on Europa potentially habitable for life.               
Europa's subsurface ocean was later indirectly confirmed by the spacecraft                 
He furthered insights regarding the atmosphere of Venus, seasonal changes on               
Mars, and Saturn's moon Titan. Sagan established that the atmosphere of Venus is           
extremely hot and dense. He also perceived global warming as a growing, man-made           
danger and likened it to the natural development of Venus into a hot life-hostile           
planet through greenhouse gases. He suggested that the seasonal changes on Mars             
were due to windblown dust, not to vegetation changes, as others had proposed.             
Sagan was a proponent of the search for extraterrestrial life. He urged the                 
scientific community to listen with large radio telescopes for signals from                 
intelligent extraterrestrial lifeforms. He advocated sending probes to other               
planets. Sagan was Editor in Chief of Icarus (a professional journal concerning             
planetary research) for 12 years. He cofounded the Planetary Society and was a             
member of the SETI Institute Board of Trustees.                                             
He was well known as a coauthor of the scientific paper that predicted nuclear             
winter would follow nuclear war. Sagan famously predicted that smoky oil fires             
in Kuwait (set by Saddam Hussein's army) would cause an ecological disaster of             
black clouds. Retired atmospheric physicist Fred Singer dismissed Sagan's                   
prediction as nonsense, predicting that the smoke would dissipate in a matter of           
Sagan believed that the Drake equation suggested that a large number of                     
extraterrestrial civilizations would form, but that the lack of evidence of such           
civilizations (the Fermi paradox) suggests that technological civilizations tend           
to destroy themselves rather quickly. This stimulated his interest in                       
identifying and publicizing ways that humanity could destroy itself, with the               
hope of avoiding such destruction and eventually becoming a space-faring species.           
Sagan, a life-long follower of liberalism, became more politically active after             
marrying leftist Ann Druyan and performed acts of civil disobedience at nuclear             
weapons sites during the Nuclear Freeze era. He spoke out against President                 
Ronald Reagan's Strategic Defense Initiative, or "Star Wars" program, which he             
felt was technically impossible to build and perfect, far more expensive to                 
create than for an enemy to defeat through decoys and other means, and                     
destabilizing to Cold War nuclear weapons disarmament progress.                             
Carl Sagan was an avid user of marijuana, although he never publicly admitted it           
during his life. Under the pseudonym "Mr. X," he wrote an essay concerning                 
cannabis smoking in the 1971 book Marihuana Reconsidered, whose editor was                 
Lester Grinspoon. In the essay Sagan commented that marijuana encouraged some of           
his works and enhanced experiences. After Sagan's death, Grinspoon disclosed               
this to Sagan's biographer Keay Davidson. When the biography, entitled Carl                 
Sagan: A Life, was published in 1999, the marijuana exposure stirred some media             
Sagan's capability to convey his ideas allowed many people to better understand             
the cosmos. He delivered the 1977/1978 Christmas Lectures for Young People at               
the Royal Institution. He wrote (with Ann Druyan, eventually his third wife) and           
narrated the highly popular thirteen part PBS television series Cosmos (modeled             
on Jacob Bronowski's The Ascent of Man); he also wrote books to popularize                 
science (The Dragons of Eden, which won a Pulitzer Prize, Broca's Brain, etc.)             
and a novel, Contact, that was a best-seller and had a film adaptation starring             
Jodie Foster in 1997. The film won the 1998 Hugo Award.                                     
From Cosmos and his frequent appearances on The Tonight Show, Sagan became                 
associated with the catch phrase "billions and billions." (He never actually               
used that phrase in Cosmos, but his distinctive delivery and frequent use of               
billions made this a favorite phrase of Johnny Carson and others doing the many             
affectionate impressions of him. Sagan took this in good humor, and his final               
book was entitled Billions and Billions - see below.) The humorous unit of the             
Sagan has now been coined to stand for any count of at least 4,000,000,000.                 
He wrote a sequel to Cosmos, Pale Blue Dot: A Vision of the Human Future in                 
Space, which was selected as a notable book of 1995 by The New York Times. Carl             
Sagan also wrote an introduction for the best selling book by Stephen Hawking, A           
Brief History of Time.                                                                     
Sagan presents a speculation concerning the origin of the swastika symbol in his           
book, Comet. Sagan hypothesized that a comet approached so close to Earth in               
antiquity that the jets of gas streaming out of it were visible, bent by the               
comet's rotation. The book Comet reproduces an ancient Chinese manuscript that             
shows comet tail varieties; most are variations on simple comet tails, but the             
last shows the comet nucleus with four bent arms extending from it, showing a               
Sagan caused mixed reactions among other professional scientists. On the one               
hand, there was general support for his popularization of science, his efforts             
to increase scientific understanding among the general public, and his positions           
in favor of skepticism and against pseudoscience.                                           
On the other hand, there was some unease that the public would misunderstand               
some of the personal positions and interests that Sagan took as being part of               
the scientific consensus rather than his own personal views, and there was some             
unease, which some believe to have been motivated in part by professional                   
jealousy, that scientific views contrary to those that Sagan took (such as on               
the severity of nuclear winter) were not being sufficiently presented to the               
His comments on the Kuwait oil well fires during the first Gulf War were shown             
later to be in error; Sagan himself acknowledged his error in print.Late in his             
life, Sagan's books developed his skeptical, naturalistic view of the world.               
In The Demon-Haunted World: Science as a Candle in the Dark, he presented tools             
for testing arguments and detecting fallacious or fraudulent ones, essentially             
advocating wide use of the scientific method.                                               
In The Demon-Haunted World, Sagan gave a list of errors he had made (including             
his predictions about the effects of the Kuwaiti oil fires) as an example of how           
science is self-correcting.                                                                 
The compilation Billions and Billions: Thoughts on Life and Death at the End of             
the Millennium, published after Sagan's death, contains essays written by Sagan,           
such as his views on abortion, and Ann Druyan's account of his death as a non-believer.     
In 1994, Apple Computer began developing the Power Macintosh 7100. They chose               
the internal code name "Carl Sagan," in honor of the astronomer.                           
Though the project name was strictly internal and never used in public marketing,           
when Sagan learned of this internal usage, he sued Apple Computer to use a                 
different project name - other projects had names like "Cold fusion" and "Piltdown         
Man", and he was displeased at being associated with what he considered                     
Though Sagan lost the suit, Apple engineers complied with his demands anyway,               
renaming the project "BHA" (Butthead Astronomer). Sagan sued Apple for libel               
over the new name, claiming that it subjected him to contempt and ridicule.                 
Sagan lost this lawsuit as well; still, the 7100 saw another name change: it was           
now called "LAW" (Lawyers Are Wimps).                                                       
Sagan is regarded by most as an atheist or agnostic, observing statements such             
as: "The idea that God is an oversized white male with a flowing beard who sits             
in the sky and tallies the fall of every sparrow is ludicrous. But if by 'God'             
one means the set of physical laws that govern the universe, then clearly there             
is such a God. This God is emotionally unsatisfying... it does not make much               
sense to pray to the law of gravity."                                                       
Sagan married three times; the famous biologist Lynn Margulis (mother of Dorion             
Sagan) in 1957, artist Linda Salzman (mother of Nick Sagan) in 1968, and author             
Ann Druyan (mother of Sasha and Sam) in 1981, to whom he remained married until             
his death.                                                                                 
After a long and difficult fight with myelodysplasia, Sagan died at the age of             
62, on December 20, 1996, at the Fred Hutchinson Cancer Research Center in                 
Seattle, Washington. Sagan was a significant figure, and his supporters credit             
his importance to his popularisation of the natural sciences, opposing both                 
restraints on science and reactionary applications of science, defending                   
democratic traditions, resisting nationalism, defending humanism, and arguing               
against geocentric and anthropocentric views.                                               
The landing site of the unmanned Mars Pathfinder spacecraft was renamed the Carl           
Sagan Memorial Station in honor of Dr. Sagan on July 5, 1997. Asteroid 2709                 
Sagan is also named in his honor.                                                           
The 1997 movie Contact, based on Sagan's novel of the same name, and finished               
after his death, ends with the dedication "For Carl."In an episode of Star Trek:           
Enterprise, a quick shot is shown of the relic rover Sojourner, part of the Mars           
Pathfinder mission, placed by a historical marker at Carl Sagan Memorial Station           
on the Martian surface. The marker displays a quote from Sagan: "Whatever the               
reason you're on Mars, I'm glad you're there, and I wish I was with you."