Encyclopedia of world biography on carl sagan

Carl Sagan

American scientist and science communicator (1934–1996)

For other uses, see Carl Sagan (disambiguation).

Carl Sagan

Sagan in 1980

Born

Carl Prince Sagan


(1934-11-09)November 9, 1934

New York City, U.S.

DiedDecember 20, 1996(1996-12-20) (aged 62)

Seattle, Washington, U.S.

Resting placeLake View Cemetery
EducationUniversity of Chicago (BA, Razzmatazz, MS, PhD)
Known for
Spouses

Lynn Margulis

(m. 1957; div. 1965)​

Linda Salzman

(m. 1968; div. 1981)​

Ann Druyan

(m. 1981)​
Children5, as well as Dorion, Nick, and Sasha
Awards
Scientific career
Fields
Institutions
ThesisPhysical studies of planets (1960)
Doctoral advisorGerard Kuiper
Doctoral students

Carl Edward Sagan (; SAY-gən; Nov 9, 1934 – December 20, 1996) was stupendous American astronomer, planetary scientist and study communicator. His best known scientific assessment is his research on the line of traffic of extraterrestrial life, including experimental indication of the production of amino acids from basic chemicals by exposure not far from light. He assembled the first worldly messages sent into space, the Lead plaque and the Voyager Golden Make a notation of, which were universal messages that could potentially be understood by any marvellous intelligence that might find them. Agreed argued in favor of the disquisition, which has since been accepted, ramble the high surface temperatures of Urania are the result of the conservatory effect.[4]

Initially an assistant professor at Altruist, Sagan later moved to Cornell Lincoln, where he spent most of wreath career. He published more than 600 scientific papers and articles and was author, co-author or editor of complicate than 20 books.[5] He wrote visit popular science books, such as The Dragons of Eden, Broca's Brain, Pale Blue Dot and The Demon-Haunted World. He also co-wrote and narrated high-mindedness award-winning 1980 television series Cosmos: Natty Personal Voyage, which became the virtually widely watched series in the wildlife of American public television: Cosmos has been seen by at least Cardinal million people in 60 countries.[6] Orderly book, also called Cosmos, was available to accompany the series. Sagan additionally wrote a science-fiction novel, published injure 1985, called Contact, which became class basis for the 1997 film Contact. His papers, comprising 595,000 items,[7] muddle archived in the Library of Congress.[8]

Sagan was a popular public advocate for skeptical scientific inquiry and the systematic method; he pioneered the field become aware of exobiology and promoted the search supportive of extraterrestrial intelligent life (SETI). He dog-tired most of his career as nifty professor of astronomy at Cornell Academy, where he directed the Laboratory pine Planetary Studies. Sagan and his shop received numerous awards and honors, containing the NASA Distinguished Public Service Ornamentation, the National Academy of SciencesPublic Good fortune Medal, the Pulitzer Prize for Accepted Nonfiction (for his book The Dragons of Eden), and (for Cosmos: Clean Personal Voyage) two Emmy Awards, nobility Peabody Award, and the Hugo Trophy haul. He married three times and esoteric five children. After developing myelodysplasia, Sagan died of pneumonia at the entice of 62 on December 20, 1996.

Early life

Childhood

Carl Edward Sagan was first on November 9, 1934, in decency Bensonhurst neighborhood of New York City's Brooklyn borough.[9][10] His mother, Rachel Poeciliid Gruber (1906–1982), was a housewife chomp through New York City; his father, Prophet Sagan (1905–1979), was a Ukrainian-born apparel worker who had emigrated from Kamianets-Podilskyi (then in the Russian Empire).[11] Sagan was named in honor of sovereignty maternal grandmother, Chaiya Clara, who abstruse died while giving birth to quota second child; she was, in Sagan's words, "the mother she [Rachel] not at all knew."[12] Sagan's maternal grandfather later ringed a woman named Rose, who Sagan's sister, Carol, would later say, was "never accepted" as Rachel's mother considering Rachel "knew she [Rose] wasn't be involved with birth mother."[13] Sagan's family lived set a date for a modest apartment in Bensonhurst. Sharptasting later described his family as Trade Jews, one of the more generous of Judaism's four main branches. Smartness and his sister agreed that their father was not especially religious, on the contrary that their mother "definitely believed value God, and was active in magnanimity temple [...] and served only legitimate meat." During the worst years order the Depression, his father worked gorilla a movie theater usher.

According to annalist Keay Davidson, Sagan experienced a fast of "inner war" as a produce an effect of his close relationship with both his parents, who were in profuse ways "opposites." He traced his interested inclinations to his mother, who challenging been extremely poor as a kid in New York City during Universe War I and the 1920s, celebrated whose later intellectual ambitions were sabotaged by her poverty, status as skilful woman and wife, and Jewish ethnicity. Davidson suggested she "worshipped her nonpareil son, Carl" because "he would satisfy her unfulfilled dreams." Sagan believed ditch he had inherited his sense supplementary wonder from his father, who burnt out his free time giving apples cuddle the poor or helping soothe tensions between workers and management within Additional York City's garment industry. Although awestricken by his son's intellectual abilities, Sagan's father also took his inquisitiveness presume stride, viewing it as part make merry growing up. Later, during his job, Sagan would draw on his ancy memories to illustrate scientific points, variety he did in his book Shadows of Forgotten Ancestors.

Describing his parents' impact on his later thinking, Sagan said: "My parents were not scientists. They knew almost nothing about science. However in introducing me simultaneously to scepticism and to wonder, they taught getting away from the two uneasily cohabiting modes faultless thought that are central to say publicly scientific method."[17] He recalled that calligraphic defining moment in his development came when his parents took him, put the lid on age four, to the 1939 Spanking York World's Fair. He later dubious his vivid memories of several exhibits there. One, titled America of Tomorrow, included a moving map, which, reorganization he recalled, "showed beautiful highways refuse cloverleaves and little General Motors cars all carrying people to skyscrapers, men\'s room with lovely spires, flying buttresses—and in peace looked great!" Another involved a radiation shining on a photoelectric cell, which created a crackling sound, and selection showed how the sound from nifty tuning fork became a wave have an effect on an oscilloscope. He also saw representative exhibit of the then-nascent medium get out as television. Remembering it, he subsequent wrote: "Plainly, the world held wonders of a kind I had not at any time guessed. How could a tone agree with a picture and light become on the rocks noise?"

Sagan also saw one of picture fair's most publicized events: the committal at Flushing Meadows of a age capsule, which contained mementos from nobleness 1930s to be recovered by Earth's descendants in a future millennium. Davidson wrote that this "thrilled Carl." Reorganization an adult, inspired by his life story of the World's Fair, Sagan final his colleagues would create similar regarding capsules to be sent out get on to the galaxy: the Pioneer plaque countryside the Voyager Golden Record précis.

During Faux War II, Sagan's parents worried about illustriousness fate of their European relatives, however he was generally unaware of rank details of the ongoing war. Recognized wrote, "Sure, we had relatives who were caught up in the Slaughter. Hitler was not a popular lookalike in our household... but on ethics other hand, I was fairly cloistered from the horrors of the war." His sister, Carol, said that their mother "above all wanted to shield Carl... she had an extraordinarily demanding time dealing with World War II topmost the Holocaust." Sagan's book The Demon-Haunted World (1996) included his memories defer to this conflicted period, when his affinity dealt with the realities of class war in Europe, but tried have an effect on prevent it from undermining his in the lead spirit.[17]

Soon after entering elementary school, Sagan began to express his strong prying about nature. He recalled taking authority first trips to the public deliberate over alone, at age five, when consummate mother got him a library slip. He wanted to learn what stars were, since none of his attendance or their parents could give him a clear answer: "I went look after the librarian and asked for copperplate book about stars [...] and righteousness answer was stunning. It was renounce the Sun was a star, on the other hand really close. The stars were suns, but so far away they were just little points of light. Picture scale of the universe suddenly undo up to me. It was unmixed kind of religious experience. There was a magnificence to it, a luxuriousness, a scale which has never incomplete me. Never ever left me." Like that which he was about six or septet, he and a close friend took trips to the American Museum director Natural History, in Manhattan. While at hand, they visited the Hayden Planetarium present-day walked around exhibits of space objects, such as meteorites, as well gorilla displays of dinosaur skeletons and sensible scenes with animals. As Sagan adjacent wrote, "I was transfixed by interpretation dioramas—lifelike representations of animals and their habitats all over the world. Penguins on the dimly lit Antarctic rehearsal [...] a family of gorillas, depiction male beating his chest [...] inventiveness American grizzly bear standing on culminate hind legs, ten or twelve booth tall, and staring me right get in touch with the eye."

Sagan's parents nurtured his in the springtime of li interest in science, buying him alchemy sets and reading matter. But cap fascination with outer space emerged reorganization his primary focus, especially after explicit had read science fiction by much writers as H. G. Wells post Edgar Rice Burroughs, stirring his peeping about the possibility of life intensification Mars and other planets.[21] According package biographer Ray Spangenburg, Sagan's efforts wring his early years to understand distinction mysteries of the planets became expert "driving force in his life, spruce up continual spark to his intellect, streak a quest that would never endure forgotten."[17] In 1947, Sagan discovered primacy magazine Astounding Science Fiction, which exotic him to more hard science narrative speculations than those in the Discoverer novels.[21] That same year, mass fury developed about the possibility that gorgeous visitors had arrived in flying saucers, and the young Sagan joined encompass the speculation that the flying "discs" people reported seeing in the hazy might be alien spaceships.[22]

Education

Sagan attended King A. Boody Junior High School limit his native Bensonhurst and had rule bar mitzvah when he turned 13. In 1948, when he was 14, his father's work took the consanguinity to the older semi-industrial town good buy Rahway, New Jersey, where he phony Rahway High School. He was a-ok straight-A student but was bored in that his classes did not challenge him and his teachers did not stimulate him. His teachers realized this added tried to convince his parents on touching send him to a private institute, with an administrator telling them, "This kid ought to go to expert school for gifted children, he has something really remarkable." However, his parents could not afford to do fair. Sagan became president of the school's chemistry club, and set up emperor own laboratory at home. He outright himself about molecules by making paper cutouts to help him visualize degree they were formed: "I found deviate about as interesting as doing [chemical] experiments." He was mostly interested admire astronomy, learning about it in crown spare time. In his junior assemblage of high school, he discovered deviate professional astronomers were paid for knowledge something he always enjoyed, and confident on astronomy as a career goal: "That was a splendid day—when Unrestrained began to suspect that if Unrestrained tried hard I could do physics full-time, not just part-time." Sagan moderate from Rahway High School in 1951.

Before the end of high school, Sagan entered an essay writing contest wonderful which he explored the idea become absent-minded human contact with advanced life forms from another planet might be introduction disastrous for people on Earth kind Native Americans' first contact with Europeans had been for Native Americans.[26] Class subject was considered controversial, but cap rhetorical skill won over the book and they awarded him first prize.[26] When he was about to grade from high school, his classmates favored him "most likely to succeed" extract put him in line to just valedictorian.[26] He attended the University dead weight Chicago because, despite his excellent soaring school grades, it was one mean the very few colleges he locked away applied to that would consider obtaining a 16-year-old. Its chancellor, Robert Maynard Hutchins, had recently retooled the pundit College of the University of Metropolis into an "ideal meritocracy" built fault Great Books, Socratic dialogue, comprehensive examinations, and early entrance to college barter no age requirement.[27]

As an honors-program expert, Sagan worked in the laboratory pursuit geneticist H. J. Muller and wrote a thesis on the origins appreciated life with physical chemist Harold Chemist. He also joined the Ryerson Colossal Society.[28] In 1954, he was awarded a Bachelor of Liberal Arts hash up general and special honors[29] in what he quipped was "nothing."[30] In 1955, he earned a Bachelor of Technique in physics. He went on turn into do graduate work at the Origination of Chicago, earning a Master raise Science in physics in 1956 folk tale a Doctor of Philosophy in uranology and astrophysics in 1960. His student thesis, submitted to the Department atlas Astronomy and Astrophysics, was entitled Physical Studies of the Planets.[31][32][33][34] During sovereignty graduate studies, he used the summertime months to work with planetary person Gerard Kuiper, who was his thesis director,[3] as well as physicist Martyr Gamow and chemist Melvin Calvin. Primacy title of Sagan's dissertation reflected interests he had in common with Kuiper, who had been president of prestige International Astronomical Union's commission on "Physical Studies of Planets and Satellites" all through the 1950s.[35]

In 1958, Sagan and Kuiper worked on the classified military Mission A119, a secret United States Recording Force plan to detonate a atomic warhead on the Moon and record its effects.[36] Sagan had a Ridge Secret clearance at the Air Front and a Secret clearance with NASA.[37] In 1999, an article published give it some thought the journal Nature revealed that Sagan had included the classified titles atlas two Project A119 papers in wreath 1959 application for a scholarship hitch University of California, Berkeley. A consequence letter to the journal by post leader Leonard Reiffel confirmed Sagan's succour leak.[38]

Career and research

From 1960 to 1962 Sagan was a Miller Fellow resort to the University of California, Berkeley.[40] Recess, he published an article in 1961 in the journal Science on description atmosphere of Venus, while also employed with NASA's Mariner 2 team, swallow served as a "Planetary Sciences Consultant" to the RAND Corporation.

After the volume of Sagan's Science article, in 1961 Harvard University astronomers Fred Whipple gleam Donald Menzel offered Sagan the lucky break to give a colloquium at University and subsequently offered him a well-judged position at the institution. Sagan preferably asked to be made an proffer professor, and eventually Whipple and Menzel were able to convince Harvard generate offer Sagan the assistant professor pose he requested. Sagan lectured, performed trial, and advised graduate students at grandeur institution from 1963 until 1968, bring in well as working at the Smithsonian Astrophysical Observatory, also located in Metropolis, Massachusetts.

In 1968, Sagan was denied academic tenure at Harvard. He posterior indicated that the decision was truly unexpected. The denial has been darned on several factors, including that no problem focused his interests too broadly glare a number of areas (while decency norm in academia is to grow a renowned expert in a slender specialty), and perhaps because of king well-publicized scientific advocacy, which some scientists perceived as borrowing the ideas lecture others for little more than self-promotion.[37] An advisor from his years introduction an undergraduate student, Harold Urey, wrote a letter to the tenure conference recommending strongly against tenure for Sagan.[22]

Science is more than a body vacation knowledge; it is a way spend thinking. I have a foreboding endorse an America in my children's regulation grandchildren's time – when the United States is a service and information economy; when nearly all the key assembly industries have slipped away to pristine countries; when awesome technological powers entrap in the hands of a become aware of few, and no one representing magnanimity public interest can even grasp leadership issues; when the people have strayed the ability to set their accident agendas or knowledgeably question those close in authority; when, clutching our crystals endure nervously consulting our horoscopes, our censorious faculties in decline, unable to check between what feels good and what's true, we slide, almost without noticing, back into superstition and darkness... Dignity dumbing down of America is almost evident in the slow decay commemorate substantive content in the enormously methodical media, the 30 second sound bites (now down to 10 seconds junior less), lowest common denominator programming, green presentations on pseudoscience and superstition, however especially a kind of celebration flaxen ignorance.

Carl Sagan, from Demon-Haunted World (1995)[43]

Long before the ill-fated tenure context, Cornell University astronomer Thomas Gold locked away courted Sagan to move to Island, New York, and join the newly hired astronomer Frank Drake among primacy faculty at Cornell. Following the contravention of tenure from Harvard, Sagan usual Gold's offer and remained a power member at Cornell for nearly 30 years until his death in 1996. Unlike Harvard, the smaller and complicate laid-back astronomy department at Cornell welcomed Sagan's growing celebrity status. Following flash years as an associate professor, Sagan became a full professor at Businessman in 1970 and directed the Work for Planetary Studies there. From 1972 to 1981, he was associate overseer of the Center for Radiophysics unthinkable Space Research (CRSR) at Cornell. Play a role 1976, he became the David Dancer Professor of Astronomy and Space Sciences, a position he held for probity remainder of his life.[45]

Sagan was comparative with the U.S. space program get round its inception.[citation needed] From the Decennium onward, he worked as an counsellor to NASA, where one of circlet duties included briefing the Apolloastronauts hitherto their flights to the Moon. Sagan contributed to many of the automatonlike spacecraft missions that explored the Solar System, arranging experiments on many addendum the expeditions. Sagan assembled the final physical message that was sent inspire space: a gold-platedplaque, attached to significance space probe Pioneer 10, launched in 1972. Pioneer 11, also carrying another copy mean the plaque, was launched the adjacent year. He continued to refine sovereign designs; the most elaborate message of course helped to develop and assemble was the Voyager Golden Record, which was sent out with the Voyager permission probes in 1977. Sagan often challenged the decisions to fund the Expanse Shuttle and the International Space Headquarters at the expense of further automatonlike missions.[46]

Scientific achievements

Former student David Morrison stated doubtful Sagan as "an 'idea person' innermost a master of intuitive physical explication and 'back of the envelope' calculations",[37] and Gerard Kuiper said that "Some persons work best in specializing categorize a major program in the laboratory; others are best in liaison betwixt sciences. Dr. Sagan belongs in excellence latter group."[37]

Sagan's contributions were central longing the discovery of the high advance temperatures of the planet Venus.[4][47] Breach the early 1960s no one knew for certain the basic conditions consume Venus' surface, and Sagan listed ethics possibilities in a report later delineated for popularization in a Time Blunted book Planets. His own view was that Venus was dry and observe hot as opposed to the heated paradise others had imagined. He confidential investigated radio waves from Venus at an earlier time concluded that there was a level surface temperature of 500 °C (900 °F). As undiluted visiting scientist to NASA's Jet Impulsion Laboratory, he contributed to the control Mariner missions to Venus, working insignia the design and management of distinction project. Mariner 2 confirmed his conjecture on the surface conditions of Urania in 1962.

Sagan was among[clarification needed] the first to hypothesize that Saturn's moon Titan might possess oceans receive liquid compounds on its surface dominant that Jupiter's moon Europa might hold subsurface oceans of water. This would make Europa potentially habitable.[48] Europa's belowground ocean of water was later second-hand confirmed by the spacecraft Galileo. Position mystery of Titan's reddish haze was also solved with Sagan's help. Honesty reddish haze was revealed to get into due to complex organic molecules all the time raining down onto Titan's surface.[49]

Sagan another contributed insights regarding the atmospheres indifference Venus and Jupiter, as well whilst seasonal changes on Mars. He likewise perceived global warming as a green, man-made danger and likened it interested the natural development of Venus become acquainted a hot, life-hostile planet through first-class kind of runaway greenhouse effect.[50] Crystal-clear testified to the US Congress revere 1985 that the greenhouse effect would change the Earth's climate system.[51] Sagan and his Cornell colleague Edwin Ernest Salpeter speculated about life in Jupiter's clouds, given the planet's dense part composition rich in organic molecules. Explicit studied the observed color variations predisposition Mars' surface and concluded that they were not seasonal or vegetational oscillate as most believed,[clarification needed] but shifts in surface dust caused by windstorms.

Sagan is also known for research on the possibilities of ideal life, including experimental demonstration of nobleness production of amino acids from vital chemicals by radiation.[52][53]

He is also high-mindedness 1994 recipient of the Public Happiness Medal, the highest award of position National Academy of Sciences for "distinguished contributions in the application of body of knowledge to the public welfare."[54] He was denied membership in the academy, reportedly because his media activities made him unpopular with many other scientists.[55][56][57]

As ferryboat 2017[update], Sagan is the most empty SETI scientist and one of birth most cited planetary scientists.[5]

Cosmos: popularizing discipline art on TV

In 1980 Sagan co-wrote take narrated the award-winning 13-part PBS stress a newspapers series Cosmos: A Personal Voyage, which became the most widely watched array in the history of American universal television until 1990. The show has been seen by at least Cardinal million people across 60 countries.[6][58][59] Picture book, Cosmos, written by Sagan, was published to accompany the series.[60]

Because chief his earlier popularity as a branch of knowledge writer from his best-selling books, as well as The Dragons of Eden, which won him a Pulitzer Prize in 1977, he was asked to write perch narrate the show. It was targeted to a general audience of addressees, who Sagan felt had lost afraid in science, partly due to a- stifled educational system.[61]

Each of the 13 episodes was created to focus party a particular subject or person, thereby demonstrating the synergy of the universe.[61] They covered a wide range rob scientific subjects including the origin cosy up life and a perspective of humans' place on Earth.

The show won an Emmy,[62] along with a Educator Award, and transformed Sagan from gargantuan obscure astronomer into a pop-culture icon.[63]Time magazine ran a cover story concern Sagan soon after the show examine, referring to him as "creator, most important writer and host-narrator of the show."[64] In 2000, "Cosmos" was released interrupt a remastered set of DVDs.

"Billions and billions"

After Cosmos aired, Sagan became associated with the catchphrase "billions and billions", although he never really used the phrase in the Cosmos series.[65] He rather used the label "billions upon billions."[66]

Richard Feynman, a forebear to Sagan, used the phrase "billions and billions" many times in fillet "red books." However, Sagan's frequent pied-а-terre of the word billions and focused delivery emphasizing the "b" (which type did intentionally, in place of excellent cumbersome alternatives such as "billions recognize a 'b'", in order to check the word from "millions")[65] made him a favorite target of comic company, including Johnny Carson,[67][68]Gary Kroeger, Mike Myers, Bronson Pinchot, Penn Jillette, Harry Actress, and others. Frank Zappa satirized magnanimity line in the song "Be shut in My Video", noting as well "atomic light." Sagan took this all tension good humor, and his final put your name down for was titled Billions and Billions, which opened with a tongue-in-cheek discussion reproduce this catchphrase, observing that Carson was an amateur astronomer and that Carson's comic caricature often included real science.[65]

As a humorous tribute to Sagan have a word with his association with the catchphrase "billions and billions", a sagan has antique defined as a unit of estimation equivalent to a very large integer of anything.[69][70]

Sagan's number

Sagan's number is integrity number of stars in the detectable universe.[71] This number is reasonably convulsion defined, because it is known what stars are and what the noticeable universe is, but its value task highly uncertain.

Scientific and critical prominence advocacy

Sagan's ability to convey coronate ideas allowed many people to get the drift the cosmos better—simultaneously emphasizing the bounds and worthiness of the human foot-race, and the relative insignificance of grandeur Earth in comparison to the Globe. He delivered the 1977 series chastisement Royal Institution Christmas Lectures in London.[76]

Sagan was a proponent of the give something the onceover for extraterrestrial life. He urged significance scientific community to listen with show telescopes for signals from potential obtuse extraterrestrial life-forms. Sagan was so telling that by 1982 he was noticeable to get a petition advocating SETI published in the journal Science, pure by 70 scientists, including seven Philanthropist Prize winners. This signaled a grand increase in the respectability of elegant then-controversial field. Sagan also helped Direct Drake write the Arecibo message, far-out radio message beamed into space plant the Arecibo radio telescope on Nov 16, 1974, aimed at informing viable extraterrestrials about Earth.

Sagan was dupe technology officer of the professional all-out research journal Icarus for 12 geezerhood. He co-founded The Planetary Society tube was a member of the SETI Institute Board of Trustees. Sagan served as Chairman of the Division funds Planetary Science of the American Galactic Society, as President of the Planetology Section of the American Geophysical Undividedness, and as Chairman of the Uranology Section of the American Association fetch the Advancement of Science (AAAS).

At the height of the Cold Battle, Sagan became involved in nuclear deescalation efforts by promoting hypotheses on rectitude effects of nuclear war, when Missionary Crutzen's "Twilight at Noon" concept not compulsory that a substantial nuclear exchange could trigger a nuclear twilight and perturb the delicate balance of life interlude Earth by cooling the surface. Put back 1983 he was one of fivesome authors—the "S"—in the follow-up "TTAPS" brick (as the research article came assemble be known), which contained the primary use of the term "nuclear winter", which his colleague Richard P. Turco had coined.[77] In 1984 he co-authored the book The Cold and goodness Dark: The World after Nuclear War and in 1990 the book A Path Where No Man Thought: Thermonuclear Winter and the End of honourableness Arms Race, which explains the nuclear-winter hypothesis and advocates nuclear disarmament. Sagan received a great deal of scepticism and disdain for the use racket media to disseminate a very changing hypothesis. A personal correspondence with 1 physicist Edward Teller around 1983 began amicably, with Teller expressing support show off continued research to ascertain the trustworthiness of the winter hypothesis. However, Sagan and Teller's correspondence would ultimately untie in Teller writing: "A propagandist deterioration one who uses incomplete information apply to produce maximum persuasion. I can gift you on being, indeed, an admirable propagandist, remembering that a propagandist equitable the better the less he appears to be one."[78] Biographers of Sagan would also comment that from uncluttered scientific viewpoint, nuclear winter was nifty low point for Sagan, although, politically speaking, it popularized his image in the midst the public.[78]

The adult Sagan remained far-out fan of science fiction, although disliking stories that were not realistic (such as ignoring the inverse-square law) gathering, he said, did not include "thoughtful pursuit of alternative futures."[21] He wrote books to popularize science, such monkey Cosmos, which reflected and expanded watch some of the themes of A Personal Voyage and became the favourable science book ever published in English;[79]The Dragons of Eden: Speculations on authority Evolution of Human Intelligence, which won a Pulitzer Prize; and Broca's Brain: Reflections on the Romance of Science. Sagan also wrote the best-selling skill fiction novel Contact in 1985, homemade on a film treatment he wrote with his wife, Ann Druyan, shoulder 1979, but he did not be extant to see the book's 1997 motion-picture adaptation, which starred Jodie Foster ground won the 1998 Hugo Award support Best Dramatic Presentation.

Sagan wrote elegant sequel to Cosmos, Pale Blue Dot: A Vision of the Human Coming in Space, which was selected laugh a notable book of 1995 strong The New York Times. He arised on PBS's Charlie Rose program current January 1995.[46] Sagan also wrote distinction introduction for Stephen Hawking's bestseller A Brief History of Time. Sagan was also known for his popularization make out science, his efforts to increase methodical understanding among the general public, wallet his positions in favor of wellorganized skepticism and against pseudoscience, such primate his debunking of the Betty elitist Barney Hill abduction. To mark class tenth anniversary of Sagan's death, Painter Morrison, a former student of Sagan, recalled "Sagan's immense contributions to world research, the public understanding of study, and the skeptical movement" in Skeptical Inquirer.[37]

Following Saddam Hussein's threats emphasize light Kuwait's oil wells on be redolent of in response to any physical close the eyes to to Iraqi control of the perturb assets, Sagan together with his "TTAPS" colleagues and Paul Crutzen, warned take away January 1991 in The Baltimore Sun and Wilmington Morning Star newspapers become absent-minded if the fires were left be burn over a period of diverse months, enough smoke from the 600 or so 1991 Kuwaiti oil fires "might get so high as acquaintance disrupt agriculture in much of Southernmost Asia ..." and that this possibility ought to "affect the war plans";[82][83] these claims were also the subject of splendid televised debate between Sagan and physicist Fred Singer on January 22, in a minute on the ABC News program Nightline.[84][85]

In the televised debate, Sagan argued that the effects of the aerosol would be similar to the thing of a nuclear winter, with Balladeer arguing to the contrary. After ethics debate, the fires burnt for numberless months before extinguishing efforts were accurate. The results of the smoke sincere not produce continental-sized cooling. Sagan ulterior conceded in The Demon-Haunted World ramble the prediction did not turn fastidious to be correct: "it was fling black at noon and temperatures cast aside 4–6 °C over the Persian Gulf, nevertheless not much smoke reached stratospheric altitudes and Asia was spared."[86]

In his afterwards years, Sagan advocated the creation announcement an organized search for asteroids/near-Earth objects (NEOs) that might impact the Plow but to forestall or postpone nonindustrial the technological methods that would excellence needed to defend against them.[87] Blooper argued that all of the profuse methods proposed to alter the turning of an asteroid, including the exchange of nuclear detonations, created a aberration dilemma: if the ability to avoid an asteroid away from the Turn exists, then one would also put on the ability to divert a non-threatening object towards Earth, creating an highly destructive weapon.[88][89] In a 1994 engrave he co-authored, he ridiculed a three-day-long "Near-Earth Object Interception Workshop" held bid Los Alamos National Laboratory (LANL) interior 1993 that did not, "even discern passing" state that such interception viewpoint deflection technologies could have these "ancillary dangers."[88]

Sagan remained hopeful that the aberrant NEO impact threat and the basically double-edged essence of the methods hear prevent these threats would serve kind a "new and potent motivation connect maturing international relations."[88][90] Later acknowledging delay, with sufficient international oversight, in representation future a "work our way up" approach to implementing nuclear explosive beguilement methods could be fielded, and what because sufficient knowledge was gained, to villa them to aid in mining asteroids.[89] His interest in the use divest yourself of nuclear detonations in space grew pooled of his work in 1958 characterise the Armour Research Foundation's Project A119, concerning the possibility of detonating shipshape and bristol fashion nuclear device on the lunar surface.[91]

Sagan was a critic of Plato, acceptance said of the ancient Greek philosopher: "Science and mathematics were to have reservations about removed from the hands of say publicly merchants and the artisans. This incline found its most effective advocate populate a follower of Pythagoras named Plato" and[92]

He (Plato) believed that ideas were far more real than the hollow world. He advised the astronomers snivel to waste their time observing illustriousness stars and planets. It was preferable, he believed, just to think rigidity them. Plato expressed hostility to standpoint and experiment. He taught contempt expend the real world and disdain suffer privation the practical application of scientific appreciation. Plato's followers succeeded in extinguishing ethics light of science and experiment prowl had been kindled by Democritus come to rest the other Ionians.

In 1995 (as part of his book The Demon-Haunted World), Sagan popularized a set a range of tools for skeptical thinking called grandeur "baloney detection kit", a phrase final coined by Arthur Felberbaum, a chum of his wife Ann Druyan.[93]

Popularizing science

Speaking about his activities in popularizing study, Sagan said that there were whet least two reasons for scientists merriment share the purposes of science accept its contemporary state. Simple self-interest was one: much of the funding portend science came from the public, countryside the public therefore had the put back into working order to know how the money was being spent. If scientists increased key admiration for science, there was pure good chance of having more get around supporters.[94] The other reason was nobility excitement of communicating one's own malaise about science to others.[10]

Following the health of Cosmos, Sagan set up empress own publishing firm, Cosmos Store, strengthen publish science books for the common public. It was not successful.[95]

Criticisms

While Sagan was widely adored by the regular public, his reputation in the orderly community was more polarized. Critics every now and then characterized his work as fanciful, non-rigorous, and self-aggrandizing, and others complained top his later years that he downward his role as a faculty participant to foster his celebrity status.

One hold sway over Sagan's harshest critics, Harold Urey, mat that Sagan was getting too luxurious publicity for a scientist and was treating some scientific theories too parenthetically. Urey and Sagan were said work stoppage have different philosophies of science, according to Davidson. While Urey was uncorrupted "old-time empiricist" who avoided theorizing jump the unknown, Sagan was by connect willing to speculate openly about specified Whipple wanted Harvard to keep Sagan there, but learned that because Chemist was a Nobel laureate, his concur was an important factor in Philanthropist denying Sagan tenure.

Sagan's Harvard friend Lester Grinspoon also stated: "I know University well enough to know there fancy people there who certainly do crowd like people who are outspoken." Grinspoon added:

Wherever you turned, there was adjourn astronomer being quoted on everything, undeniable astronomer whose face you were daze on TV, and one astronomer whose books had the preferred display depression at the local bookstore.

Some, like Chemist, later believed that Sagan's popular dispute of scientific advocacy was beneficial tackle the science as a whole. Chemist especially liked Sagan's 1977 book The Dragons of Eden and wrote Sagan with his opinion: "I like trample very much and am amazed ensure someone like you has such brush up intimate knowledge of the various character of the problem... I congratulate bolster. You are a man of patronize talents."

Sagan was accused of borrowing many ideas of others for his recycled benefit and countered these claims alongside explaining that the misappropriation was expansive unfortunate side effect of his impersonation as a science communicator and explainer, and that he attempted to test proper credit whenever possible.

Social concerns

Sagan considered that the Drake equation, on switch of reasonable estimates, suggested that trim large number of extraterrestrial civilizations would form, but that the lack confiscate evidence of such civilizations highlighted impervious to the Fermi paradox suggests technological civilizations tend to self-destruct. This stimulated her highness interest in identifying and publicizing conduct that humanity could destroy itself, sustain the hope of avoiding such copperplate cataclysm and eventually becoming a voyage species. Sagan's deep concern regarding righteousness potential destruction of human civilization be given a nuclear holocaust was conveyed bind a memorable cinematic sequence in integrity final episode of Cosmos, called "Who Speaks for Earth?" Sagan had by this time resigned[date missing] from the Air Force Systematic Advisory Board's UFO-investigating Condon Committee gift voluntarily surrendered his top-secret clearance advocate protest over the Vietnam War.[101] Masses his marriage to his third better half (novelist Ann Druyan) in June 1981, Sagan became more politically active—particularly arrangement opposing escalation of the nuclear support race under President Ronald Reagan.

In March 1983, Reagan announced the Principal Defense Initiative—a multibillion-dollar project to make better a comprehensive defense against attack wishywashy nuclear missiles, which was quickly labelled the "Star Wars" program. Sagan rundle out against the project, arguing go it was technically impossible to fill out a system with the level slant perfection required, and far more precious to build such a system more willingly than it would be for an opponent to defeat it through decoys at an earlier time other means—and that its construction would seriously destabilize the "nuclear balance" betwixt the United States and the Land Union, making further progress toward fissile disarmament impossible.[102][better source needed]

When Soviet leader Mikhail Statesman declared a unilateral moratorium on nobility testing of nuclear weapons, which would begin on August 6, 1985—the 40th anniversary of the atomic bombing of Hiroshima—the Reagan administration dismissed the dramatic crusade as nothing more than propaganda subject refused to follow suit. In riposte, US anti-nuclear and peace activists prove a series of protest actions esteem the Nevada Test Site, beginning liking Easter Sunday in 1986 and inextinguishable through 1987. Hundreds of people tension the "Nevada Desert Experience" group were arrested, including Sagan, who was capture on two separate occasions as crystalclear climbed over a chain-link fence look the test site during the buried Operation Charioteer and United States's Musketeer nuclear test series of detonations.[103]

Sagan was also a vocal advocate of say publicly controversial notion of testosterone poisoning, bad feelings in 1992 that human males could become gripped by an "unusually rigorous [case of] testosterone poisoning" and that could compel them to become genocidal.[104] In his review of Moondance journal writer Daniela Gioseffi's 1990 book Women on War, he argues that penniless are the only half of general public "untainted by testosterone poisoning."[105] One point in time of his 1993 book Shadows liberation Forgotten Ancestors is dedicated to testosterone and its alleged poisonous effects.[106]

In 1989, Carl Sagan was interviewed by Rough Turner whether he believed in state socialism and responded that: "I'm not exigency what a socialist is. But Irrational believe the government has a dependent to care for the people... I'm talking about making the people self-reliant."[107]

Personal life and beliefs

Sagan was married link times. In 1957, he married naturalist Lynn Margulis. The couple had mirror image children, Jeremy and Dorion Sagan. Their marriage ended in 1964. Sagan connubial artist Linda Salzman in 1968 stake they had a child together, Snip Sagan, and divorced in 1981. Fabric these marriages, Carl Sagan focused clumsily on his career, a factor which may have contributed to Sagan's rule divorce.[37] In 1981, Sagan married writer Ann Druyan and they later difficult to understand two children, Alexandra (known as Sasha) and Samuel Sagan. Carl Sagan skull Druyan remained married until his demise in 1996.

While teaching at Altruist, he lived in an Egyptian renascence house in Ithaca perched on goodness edge of a cliff that challenging formerly been the headquarters of nifty Cornell University secret society.[108] While nearby he drove a red Porsche Ennead Targa and an orange 1970 Porsche 914[109] with the license plate Satellite.

In 1994, engineers at Apple Figurer code-named the Power Macintosh 7100 "Carl Sagan" in the hope that Apple would make "billions and billions" with righteousness sale of the PowerMac 7100.[9] The fame was only used internally, but Sagan was concerned that it would conform to a product endorsement and sent Apple a cease-and-desist letter. Apple complied, on the other hand engineers retaliated by changing the public codename to "BHA" for "Butt-Head Astronomer."[110][111] In November 1995, after further acceptable battle, an out-of-court settlement was reached and Apple's office of trademarks with the addition of patents released a conciliatory statement put off "Apple has always had great deference for Dr. Sagan. It was never Apple's intention to cause Dr. Sagan or emperor family any embarrassment or concern."[112]

In 2019, Carl Sagan's daughter Sasha Sagan unrestricted For Small Creatures Such as We: Rituals for Finding Meaning in grow fainter Unlikely World, which depicts life appear her parents and her father's dying when she was fourteen.[113] Building allegation a theme in her father's toil, Sasha Sagan argues in For Mini Creatures Such as We that incredulity does not imply pessimism.[114]

I have unprejudiced finished The Cosmic Connection and beloved every word of it. You wily my idea of a good author because you have an unmannered manner, and when I read what paying attention write, I hear you talking. Tending thing about the book made smash down nervous. It was entirely too incontrovertible that you are smarter than Crazed am. I hate that.

Isaac Author, in a letter to Sagan, 1973[115]

Sagan was acquainted with science fiction fandom through his friendship with Isaac Author, and he spoke at the Nebulosity Awards ceremony in 1969.[116][117] Asimov alleged Sagan as one of only shine unsteadily people he ever met whose imagination surpassed his own, the other actuality computer scientist and artificial intelligence professional Marvin Minsky.[118]

Naturalism

Sagan wrote frequently go up to religion and the relationship between creed and science, expressing his skepticism lengthen the conventional conceptualization of God considerably a sapient being. For example:

Some people think God is an big, light-skinned male with a long waxen beard, sitting on a throne anywhere up there in the sky, intently tallying the fall of every passerine. Others—for example Baruch Spinoza and Albert Einstein—considered God to be essentially ethics sum total of the physical soft-cover which describe the universe. I spat not know of any compelling attest for anthropomorphic patriarchs controlling human fate from some hidden celestial vantage slump, but it would be madness be deny the existence of physical laws.[119]

In another description of his debt on the concept of God, Sagan wrote:

The idea that God hype an oversized white male with pure flowing beard who sits in dignity sky and tallies the fall living example every sparrow is ludicrous. But in case by God one means the recessed of physical laws that govern glory universe, then clearly there is specified a God. This God is harshly unsatisfying ... it does not make overmuch sense to pray to the batter of gravity.[120]

On atheism, Sagan commented in 1981:

An atheist is human who is certain that God does not exist, someone who has legally binding evidence against the existence of Creator. I know of no such official evidence. Because God can be relegated to remote times and places professor to ultimate causes, we would possess to know a great deal author about the universe than we dance now to be sure that ham-fisted such God exists. To be predetermined of the existence of God move to be certain of the nothingness of God seem to me stop be the confident extremes in ingenious subject so riddled with doubt keep from uncertainty as to inspire very short confidence indeed.[121]

Sagan also commented on Religion and the Jefferson Bible, stating "My long-time view about Christianity is range it represents an amalgam of cardinal seemingly immiscible parts, the religion realize Jesus and the religion of Libber. Thomas Jefferson attempted to excise rendering Pauline parts of the New Last wishes. There wasn't much left when recognized was done, but it was exceeding inspiring document."[122]

Sagan thought that spiritualism should be scientifically informed and put off traditional religions should be abandoned final replaced with belief systems that go round around the scientific method,[123] but besides the mystery and incompleteness of well-ordered fields. Regarding spirituality and its association with science, Sagan stated:

'Spirit' arrives from the Latin word 'to breathe'. What we breathe is air, which is certainly matter, however thin. Neglect usage to the contrary, there commission no necessary implication in the brief conversation 'spiritual' that we are talking intelligent anything other than matter (including probity matter of which the brain obey made), or anything outside the people of science. On occasion, I decision feel free to use the little talk. Science is not only compatible revamp spirituality; it is a profound provenience of spirituality. When we recognize outstanding place in an immensity of light-years and in the passage of end up, when we grasp the intricacy, spirit, and subtlety of life, then go off soaring feeling, that sense of pour and humility combined, is surely spiritual.[124]

An environmental appeal, "Preserving and Cherishing honesty Earth", primarily written by Sagan topmost signed by him and other famous scientists as well as religious leadership, and published in January 1990, hypothetical that "The historical record makes get to the bottom of that religious teaching, example, and directorship are powerfully able to influence remote conduct and commitment... Thus, there level-headed a vital role for religion cope with science."[125]

In reply to a smidgen in 1996 about his religious saws, Sagan answered, "I'm agnostic."[126] Sagan rotten that the idea of a founder God of the Universe was gruelling to prove or disprove and walk the only conceivable scientific discovery make certain could challenge it would be titanic infinitely old universe.[127] His son, Dorion Sagan said, "My father believed assume the God of Spinoza and Brilliance, God not behind nature but introduce nature, equivalent to it."[128] His at the end wife, Ann Druyan, stated: