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.
Education and scientific career
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.
Scientific achievements
He was well known as a coauthor of the scientific paper that warned of the dangers of nuclear winter. 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 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, making them habitable for life. Europa's subsurface ocean was later indirectly confirmed by the spacecraft Galileo.
Scientific advocacy
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.
Social concerns
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 liberal, became radicalized after marrying leftist Ann Druyan and performed acts of civil disobedience at nuclear weapons sites during the Nuclear Freeze era.
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 Sagan: A Life, was published in 1999, the marijuana exposure stirred some media attention.
Popularization of science
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; 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.) 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 swastika.
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 public. His comments on the Kuwait oil well fires during the first Gulf War were shown later to be in error.
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.
Personality
Sagan was considered by some to have an inflated ego. 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 pseudoscience. 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 has been widely portrayed as an atheist or agnostic, citing quotes 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 in 1981, to whom he remained married until his death.
Legacy
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 (see above), based on Sagan's novel of the same name, and finished after his death, movingly ends with the dedication "For Carl."
Awards and medals
Apollo Achievement Award - National Aeronautics and Space Administration
Chicken Little Honorable Mention - 1991 - National Anxiety Center
Distinguished Public Service - National Aeronautics and Space Administration
Emmy - Outstanding individual achievement - 1981 - PBS series Cosmos
Emmy - Outstanding Informational Series - 1981 - PBS series Cosmos
Exceptional Scientific Achievement Medal - National Aeronautics and Space Administration
Helen Caldicott Leadership Award - Women's Action for Nuclear Disarmament
Homer Award - 1997 - Contact
Hugo Award - 1998 - Contact
Hugo Award - 1981 - Cosmos
Hugo Award - 1997 - The Demon-Haunted World
Humanist of the Year - 1981 - awarded by the American Humanist Association
In Praise of Reason Award - 1987 - Committee for the Scientific Investigation of Claims of the Paranormal
Isaac Asimov Award - 1994 - Committee for the Scientific Investigation of Claims of the Paranormal
John F. Kennedy Astronautics Award - American Astronautical Society
John W. Campbell Memorial Award - 1974 - The Cosmic Connection
Klumpke-Roberts Award of the Astronomical Society of the Pacific - 1974
Konstantin Tsiolkovsky Medal - Soviet Cosmonauts Federation
Locus Poll Award 1986 - Contact
Lowell Thomas Award - Explorers Club - 75th Anniversary
Masursky Award - American Astronomical Society
Peabody - 1980 - PBS series Cosmos
Public Welfare Medal - 1994 - National Academy of Sciences
Pulitzer Prize for Literature - 1978 - The Dragons of Eden
SF Chronicle Award - 1998 - Contact
Carl Sagan Memorial Award - Named in his honor
Related books and media
Sagan, Carl and Jonathon Norton Leonard and editors of Life, Planets. Time, Inc., 1966
Sagan, Carl and I.S. Shklovskii, Intelligent Life in the Universe. Random House, 1966
Sagan, Carl, Communication with Extraterrestrial Intelligence. MIT Press, 1973
Sagan, Carl, et. al. Mars and the Mind of Man. Harper & Row, 1973
Sagan, Carl, Other Worlds. Bantam Books, 1975
Sagan, Carl, et. al. Murmurs of Earth: The Voyager Interstellar Record. Random House, 1977
Sagan, Carl et. al. The Nuclear Winter: The World After Nuclear War. Sidgwick & Jackson, 1985
Sagan, Carl, Contact. Simon and Schuster, 1985; Reissued August 1997 by Doubleday Books, ISBN 1568654243, 352 pgs
Sagan, Carl and Richard Turco, A Path Where No Man Thought: Nuclear Winter and the End of the Arms Race. Random House, 1990
Sagan, Carl, The Dragons of Eden: Speculations on the Evolution of Human Intelligence. Ballantine Books, December 1989, ISBN 0345346297, 288 pgs
Sagan, Carl, Broca's Brain: Reflections on the Romance of Science. Ballantine Books, October 1993, ISBN 0345336895, 416 pgs
Sagan, Carl and Ann Druyan, Shadows of Forgotten Ancestors: A Search for Who We Are. Ballantine Books, October 1993, ISBN 0345384725, 528 pgs
Sagan, Carl and Ann Druyan, Comet. Ballantine Books, February 1997, ISBN 0345412222, 496 pgs
Sagan, Carl, Pale Blue Dot: A Vision of the Human Future in Space. Ballantine Books, September 1997, ISBN 0345376595, 384 pgs
Sagan, Carl and Ann Druyan, Billions & Billions: Thoughts on Life and Death at the Brink of the Millennium. Ballantine Books, June 1998, ISBN 0345379187, 320 pgs
Sagan, Carl, The Demon-Haunted World: Science As a Candle in the Dark. Ballantine Books, March 1997, ISBN 0345409469, 480 pgs
Sagan, Carl and Jerome Agel, Cosmic Connection: An Extraterrestrial Perspective. Cambridge University Press, January 15, 2000, ISBN 0521783038, 301 pgs
Sagan, Carl, Cosmos. Random House, May 7, 2002, ISBN 0375508325, 384 pgs
Zemeckis, Robert, Contact. Warner Studios, 1997, ASIN 0790736330 IMDB
Davidson, Keay, Carl Sagan: A Life. John Wiley & Sons, August 31, 2000, ISBN 0471395366, 560 pgs
