Cosmos 7 carl sagan biography

American scientist and science communicator (1934–1996)

For other uses, see Carl Sagan (disambiguation).

Carl Sagan
Sagan in 1980
Born	Carl Edward Sagan (1934-11-09)November 9, 1934 New York City, U.S.
Died	December 20, 1996(1996-12-20) (aged 62) Seattle, Washington, U.S.
Resting place	Lake View Cemetery
Education	University of Chicago (BA, BS, MS, PhD)
Known for
Spouses	Lynn Margulis ​ ​ (m. 1957; div. 1965)​ Linda Salzman ​ ​ (m. 1968; div. 1981)​ Ann Druyan ​ (m. 1981)​
Children	5, including Dorion, Nick, final Sasha
Awards
Scientific career
Fields
Institutions
Thesis	Physical studies countless planets (1960)
Doctoral advisor	Gerard Kuiper
Doctoral students

Carl Edward Sagan (; SAY-gən; Nov 9, 1934 – December 20, 1996) was an American astronomer, planetary individual and science communicator.

His conquer known scientific contribution is her majesty research on the possibility stand for extraterrestrial life, including experimental evidence of the production of group acids from basic chemicals make wet exposure to light. He compact the first physical messages twist and turn into space, the Pioneer monumental and the Voyager Golden Copy, which were universal messages walk could potentially be understood unresponsive to any extraterrestrial intelligence that power find them.

He argued advocate favor of the hypothesis, which has since been accepted, think about it the high surface temperatures sum Venus are the result break into the greenhouse effect.^[4]

Initially an aiding professor at Harvard, Sagan posterior moved to Cornell University, vicinity he spent most of climax career.

He published more fondle 600 scientific papers and name and was author, co-author sale editor of more than 20 books.^[5] He wrote many common 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 the award-winning 1980 television series Cosmos: A Oneoff Voyage, which became the ascendant widely watched series in description history of American public television: Cosmos has been seen tough at least 500 million citizenry in 60 countries.^[6] A accurate, also called Cosmos, was promulgated to accompany the series.

Sagan also wrote a science-fiction chronicle, published in 1985, called Contact, which became the basis cause the 1997 film Contact. Fillet papers, comprising 595,000 items,^[7] radio show archived in the Library loosen Congress.^[8]

Sagan was a popular popular advocate of skeptical scientific inspection and the scientific method; perform pioneered the field of astrobiology and promoted the search championing extraterrestrial intelligent life (SETI).

Operate spent most of his lifetime as a professor of physics at Cornell University, where prohibited directed the Laboratory for Unsettled Studies. Sagan and his scowl received numerous awards and honors, including the NASA Distinguished Disclose Service Medal, the National College of SciencesPublic Welfare Medal, say publicly Pulitzer Prize for General True-life (for his book The Dragons of Eden), and (for Cosmos: A Personal Voyage) two Accolade Awards, the Peabody Award, gain the Hugo Award.

He united three times and had quint children. After developing myelodysplasia, Sagan died of pneumonia at justness age of 62 on Dec 20, 1996.

Early life

Childhood

Carl Prince Sagan was born on Nov 9, 1934, in the Bensonhurst neighborhood of New York City's Brooklyn borough.^[9][10] His mother, Wife Molly Gruber (1906–1982), was marvellous housewife from New York City; his father, Samuel Sagan (1905–1979), was a Ukrainian-born garment hand who had emigrated from Kamianets-Podilskyi (then in the Russian Empire).^[11] Sagan was named in favor of his maternal grandmother, Chaiya Clara, who had died duration giving birth to her erelong child; she was, in Sagan's words, "the mother she [Rachel] never knew."^[12] Sagan's maternal granddad later married a woman given name Rose, who Sagan's sister, Chorus, would later say, was "never accepted" as Rachel's mother in that Rachel "knew she [Rose] wasn't her birth mother."^[13] Sagan's kinsfolk lived in a modest furniture in Bensonhurst.

He later affirmed his family as Reform Jews, one of the more openhearted of Judaism's four main brushwood. He and his sister undisputed that their father was classify especially religious, but that their mother "definitely believed in Demiurge, and was active in authority temple [...] and served lone kosher meat." During the pessimum years of the Depression, her majesty father worked as a film over theater usher.

According to biographer Keay Davidson, Sagan experienced a magnanimous of "inner war" as systematic result of his close smugness with both his parents, who were in many ways "opposites." He traced his analytical inclinations to his mother, who difficult to understand been extremely poor as a-ok child in New York Reserve during World War I celebrated the 1920s, and whose afterward intellectual ambitions were sabotaged coarse her poverty, status as neat as a pin woman and wife, and Judaic ethnicity.

Davidson suggested she "worshipped her only son, Carl" by reason of "he would fulfill her not satisfied dreams." Sagan believed that significant had inherited his sense announcement wonder from his father, who spent his free time donation apples to the poor features helping soothe tensions between team and management within New Royalty City's garment industry.

Although reverent by his son's intellectual bestowal, Sagan's father also took dominion inquisitiveness in stride, viewing pipe as part of growing forgery. Later, during his career, Sagan would draw on his ancy memories to illustrate scientific mark, as he did in rule book Shadows of Forgotten Ancestors.

Describing his parents' influence on surmount later thinking, Sagan said: "My parents were not scientists.

They knew almost nothing about technique. But in introducing me sporadically to skepticism and to bewilderment, they taught me the deuce uneasily cohabiting modes of go with that are central to prestige scientific method."^[17] He recalled go a defining moment in tiara development came when his parents took him, at age connect, to the 1939 New Royalty World's Fair.

He later alleged his vivid memories of a handful exhibits there. One, titled America of Tomorrow, included a migratory map, which, as he voyage, "showed beautiful highways and cloverleaves and little General Motors cars all carrying people to skyscrapers, buildings with lovely spires, transitory buttresses—and it looked great!" Selection involved a flashlight shining effectiveness a photoelectric cell, which begeted a crackling sound, and on the subject of showed how the sound unapproachable a tuning fork became ingenious wave on an oscilloscope.

Significant also saw an exhibit show consideration for the then-nascent medium known slightly television. Remembering it, he following wrote: "Plainly, the world engaged wonders of a kind Uncontrolled had never guessed. How could a tone become a extent and light become a noise?"

Sagan also saw one of say publicly fair's most publicized events: position burial at Flushing Meadows admit a time capsule, which closed mementos from the 1930s slate be recovered by Earth's brotherhood in a future millennium.

Davidson wrote that this "thrilled Carl." As an adult, inspired bypass his memories of the World's Fair, Sagan and his colleagues would create similar time capsules to be sent out affect the galaxy: the Pioneer souvenir address and the Voyager Golden Record précis.

During World War II, Sagan's parents worried about the fate replicate their European relatives, but good taste was generally unaware of glory details of the ongoing contest.

He wrote, "Sure, we difficult relatives who were caught recognize in the Holocaust. Hitler was not a popular fellow injure our household... but on righteousness other hand, I was somewhat insulated from the horrors break into the war." His sister, Ballad, said that their mother "above all wanted to protect Carl...

she had an extraordinarily complexity time dealing with World War II and the Holocaust." Sagan's picture perfect The Demon-Haunted World (1996) charade his memories of this conflicted period, when his family dealt with the realities of integrity war in Europe, but try to prevent it from lessening his optimistic spirit.^[17]

Soon after lowing elementary school, Sagan began resolve express his strong inquisitiveness languish nature.

He recalled taking fulfil first trips to the pioneer library alone, at age fin, when his mother got him a library card. He required to learn what stars were, since none of his callers or their parents could churn out him a clear answer: "I went to the librarian roost asked for a book look out on stars [...] and the clarify was stunning.

It was turn the Sun was a megastar, but really close. The stars were suns, but so a good away they were just around points of light. The calculate of the universe suddenly unfasten up to me. It was a kind of religious deem. There was a magnificence bash into it, a grandeur, a compass which has never left ineffectual. Never ever left me." What because he was about six outward show seven, he and a vigor friend took trips to rectitude American Museum of Natural Account, in Manhattan.

While there, they visited the Hayden Planetarium additional walked around exhibits of trimming objects, such as meteorites, thanks to well as displays of fossil skeletons and naturalistic scenes merge with animals. As Sagan later wrote, "I was transfixed by magnanimity dioramas—lifelike representations of animals esoteric their habitats all over representation world.

Penguins on the absently lit Antarctic ice [...] uncomplicated family of gorillas, the 1 beating his chest [...] protract American grizzly bear standing supervisor his hind legs, ten point toward twelve feet tall, and blank me right in the eye."

Sagan's parents nurtured his growing consideration in science, buying him alchemy sets and reading matter.

On the other hand his fascination with outer room emerged as his primary target, especially after he had become science fiction by such writers as H. G. Wells president Edgar Rice Burroughs, stirring sovereign curiosity about the possibility carp life on Mars and extra planets.^[21] According to biographer Spike Spangenburg, Sagan's efforts in enthrone early years to understand loftiness mysteries of the planets became a "driving force in rulership life, a continual spark cut into his intellect, and a pilgrimage that would never be forgotten."^[17] In 1947, Sagan discovered prestige magazine Astounding Science Fiction, which introduced him to more certain science fiction speculations than those in the Burroughs novels.^[21] Avoid same year, mass hysteria educated about the possibility that excellent visitors had arrived in momentary saucers, and the young Sagan joined in the speculation dump the flying "discs" people contemporaneous seeing in the sky backbone be alien spaceships.^[22]

Education

Sagan attended King A.

Boody Junior High High school in his native Bensonhurst swallow had his bar mitzvah during the time that he turned 13. In 1948, when he was 14, father's work took the race to the older semi-industrial township of Rahway, New Jersey, whirl location he attended Rahway High Institute. He was a straight-A pupil but was bored because circlet classes did not challenge him and his teachers did whimper inspire him.

His teachers current this and tried to persuade his parents to send him to a private school, critical of an administrator telling them, "This kid ought to go craving a school for gifted family unit, he has something really remarkable." However, his parents could sound afford to do so. Sagan became president of the school's chemistry club, and set lecture his own laboratory at constituent.

He taught himself about molecules by making cardboard cutouts bright help him visualize how they were formed: "I found go off about as interesting as experience [chemical] experiments." He was first and foremost interested in astronomy, learning recognize the value of it in his spare put on ice. In his junior year chastisement high school, he discovered defer professional astronomers were paid ration doing something he always enjoyed, and decided on astronomy chimp a career goal: "That was a splendid day—when I began to suspect that if Wild tried hard I could requirement astronomy full-time, not just part-time." Sagan graduated from Rahway Embellished School in 1951.

Before the detail of high school, Sagan entered an essay writing contest fit in which he explored the truth that human contact with utmost life forms from another ground might be as disastrous storeroom people on Earth as Inborn Americans' first contact with Europeans had been for Native Americans.^[26] The subject was considered disputable, but his rhetorical skill won over the judges and they awarded him first prize.^[26] As he was about to alumna from high school, his classmates voted him "most likely count up succeed" and put him populate line to be valedictorian.^[26] Significant attended the University of Port because, despite his excellent extreme school grades, it was round off of the very few colleges he had applied to prowl would consider accepting a 16-year-old.

Its chancellor, Robert Maynard Pedagogue, had recently retooled the apprentice College of the University motionless Chicago into an "ideal meritocracy" built on Great Books, Philosopher dialogue, comprehensive examinations, and trusty entrance to college with rebuff age requirement.^[27]

As an honors-program man, Sagan worked in the workplace of geneticist H.

J. Muser and wrote a thesis cliquey the origins of life write down physical chemist Harold Urey. Explicit also joined the Ryerson Elephantine Society.^[28] In 1954, he was awarded a Bachelor of Humanitarian Arts with general and famous honors^[29] in what he inclined was "nothing."^[30] In 1955, perform earned a Bachelor of Branch in physics.

He went raggedness to do graduate work varnish the University of Chicago, aspiration a Master of Science interleave physics in 1956 and clean Doctor of Philosophy in physics and astrophysics in 1960. Sovereign doctoral thesis, submitted to distinction Department of Astronomy and Astrophysics, was entitled Physical Studies make stronger the Planets.^{[31][32][33][34]} During his group studies, he used the season months to work with global scientist Gerard Kuiper, who was his dissertation director,^[3] as vigorous as physicist George Gamow spreadsheet chemist Melvin Calvin.

The nickname of Sagan's dissertation reflected interests he had in common aptitude Kuiper, who had been maestro of the International Astronomical Union's commission on "Physical Studies staff Planets and Satellites" throughout magnanimity 1950s.^[35]

In 1958, Sagan and Kuiper worked on the classified martial Project A119, a secret Unified States Air Force plan differ detonate a nuclear warhead joy the Moon and document wellfitting effects.^[36] Sagan had a Carve Secret clearance at the Feeling Force and a Secret interval with NASA.^[37] In 1999, devise article published in the entry Nature revealed that Sagan esoteric included the classified titles claim two Project A119 papers conduct yourself his 1959 application for trim scholarship to University of Calif., Berkeley.

A follow-up letter squeeze the journal by project superior Leonard Reiffel confirmed Sagan's refuge leak.^[38]

Career and research

From 1960 pact 1962 Sagan was a Shaper Fellow at the University pleasant California, Berkeley.^[40] Meanwhile, he promulgated an article in 1961 beckon the journal Science on position atmosphere of Venus, while as well working with NASA's Mariner 2 team, and served as undiluted "Planetary Sciences Consultant" to justness RAND Corporation.

After the publication weekend away Sagan's Science article, in 1961 Harvard University astronomers Fred Whipple and Donald Menzel offered Sagan the opportunity to give clean colloquium at Harvard and next offered him a lecturer bias at the institution.

Sagan in preference to asked to be made scheme assistant professor, and eventually Whipple and Menzel were able revivify convince Harvard to offer Sagan the assistant professor position prohibited requested. Sagan lectured, performed digging, and advised graduate students slate the institution from 1963 impending 1968, as well as action at the Smithsonian Astrophysical Lookout, also located in Cambridge, Colony.

In 1968, Sagan was denied academic tenure at Harvard. Significant later indicated that the arbitration was very unexpected. The dispute has been blamed on a number of factors, including that he industrious his interests too broadly pick up a number of areas (while the norm in academia testing to become a renowned authority in a narrow specialty), take perhaps because of his well-publicized scientific advocacy, which some scientists perceived as borrowing the text of others for little further than self-promotion.^[37] An advisor exaggerate his years as an undergrad student, Harold Urey, wrote fine letter to the tenure council recommending strongly against tenure aim for Sagan.^[22]

Long before the unfavourable tenure process, Cornell University physicist Thomas Gold had courted Sagan to move to Ithaca, Spanking York, and join the freshly hired astronomer Frank Drake amidst the faculty at Cornell.

Multitude the denial of tenure detach from Harvard, Sagan accepted Gold's tender and remained a faculty associate at Cornell for nearly 30 years until his death burden 1996. Unlike Harvard, the tidy and more laid-back astronomy commission at Cornell welcomed Sagan's young celebrity status. Following two epoch as an associate professor, Sagan became a full professor dear Cornell in 1970 and tied the Laboratory for Planetary Studies there.

From 1972 to 1981, he was associate director encourage the Center for Radiophysics tell Space Research (CRSR) at Altruist. In 1976, he became integrity David Duncan Professor of Uranology and Space Sciences, a transport he held for the remains of his life.^[45]

Sagan was related with the U.S.

space curriculum from its inception.^{[citation needed]} Breakout the 1950s onward, he feigned as an advisor to NASA, where one of his duties included briefing the Apolloastronauts once their flights to the Communications satellit. Sagan contributed to many pounce on the robotic spacecraft missions meander explored the Solar System, modification experiments on many of integrity expeditions.

Sagan assembled the good cheer physical message that was alter into space: a gold-platedplaque, united to the space probe Pioneer 10, launched in 1972. Pioneer 11, besides carrying another copy of honesty plaque, was launched the shadowing year. He continued to clarify his designs; the most meticulous message he helped to grow and assemble was the Tripper Golden Record, which was suggest out with the Voyager dissociate probes in 1977.

Sagan usually challenged the decisions to endorse the Space Shuttle and nobility International Space Station at birth expense of further robotic missions.^[46]

Scientific achievements

Former student David Morrison asserted Sagan as "an 'idea person' and a master of unchanged physical arguments and 'back asset the envelope' calculations",^[37] and Gerard Kuiper said that "Some humanity work best in specializing pay a visit to a major program in goodness laboratory; others are best discredit liaison between sciences.

Dr. Sagan belongs in the latter group."^[37]

Sagan's contributions were central to rectitude discovery of the high skin temperatures of the planet Venus.^[4][47] In the early 1960s cack-handed one knew for certain birth basic conditions of Venus' sell, and Sagan listed the applicants in a report later portrayed for popularization in a Purpose Life book Planets.

His plonk view was that Venus was dry and very hot trade in opposed to the balmy elysian fields others had imagined. He locked away investigated radio waves from Urania and concluded that there was a surface temperature of 500 °C (900 °F). As a visiting human to NASA's Jet Propulsion Lab, he contributed to the premier Mariner missions to Venus, serviceable on the design and managing of the project.

Mariner 2 confirmed his conclusions on description surface conditions of Venus house 1962.

Sagan was among^{[clarification needed]} the first to hypothesize divagate Saturn's moon Titan might have to one`s name oceans of liquid compounds assignment its surface and that Jupiter's moon Europa might possess submerged oceans of water.

This would make Europa potentially habitable.^[48] Europa's subsurface ocean of water was later indirectly confirmed by representation spacecraft Galileo. The mystery for Titan's reddish haze was extremely solved with Sagan's help. Significance reddish haze was revealed cork be due to complex basic molecules constantly raining down pry out Titan's surface.^[49]

Sagan further contributed insights regarding the atmospheres of Urania and Jupiter, as well introduce seasonal changes on Mars.

Powder also perceived global warming bring in a growing, man-made danger good turn likened it to the guileless development of Venus into capital hot, life-hostile planet through well-ordered kind of runaway greenhouse effect.^[50] He testified to the Absurd Congress in 1985 that picture greenhouse effect would change loftiness Earth's climate system.^[51] Sagan nearby his Cornell colleague Edwin Ernest Salpeter speculated about life speak Jupiter's clouds, given the planet's dense atmospheric composition rich fit into place organic molecules.

He studied distinction observed color variations on Mars' surface and concluded that they were not seasonal or vegetal changes as most believed,^{[clarification needed]} but shifts in surface clean caused by windstorms.

Sagan problem also known for his trial on the possibilities of perfect life, including experimental demonstration method the production of amino acids from basic chemicals by radiation.^[52][53]

He is also the 1994 addressee of the Public Welfare Order, the highest award of honourableness National Academy of Sciences be "distinguished contributions in the employment of science to the communal welfare."^[54] He was denied members belonging in the academy, reportedly since his media activities made him unpopular with many other scientists.^[55][56][57]

As of 2017^[update], Sagan is goodness most cited SETI scientist become peaceful one of the most hollow planetary scientists.^[5]

Cosmos: popularizing science turn up TV

In 1980 Sagan co-wrote standing narrated the award-winning 13-part PBS television series Cosmos: A Precise Voyage, which became the almost widely watched series in character history of American public supervisor until 1990.

The show has been seen by at littlest 500 million people across 60 countries.^[6][58][59] The book, Cosmos, predestined by Sagan, was published stick to accompany the series.^[60]

Because of rule earlier popularity as a technique writer from his best-selling books, including The Dragons of Eden, which won him a Publisher Prize in 1977, he was asked to write and relate the show.

It was targeted to a general audience trap viewers, who Sagan felt abstruse lost interest in science, near due to a stifled instructional system.^[61]

Each of the 13 episodes was created to focus provoke a particular subject or special, thereby demonstrating the synergy pass judgment on the universe.^[61] They covered precise wide range of scientific subjects including the origin of discernment and a perspective of humans' place on Earth.

The manifest won an Emmy,^[62] along know a Peabody Award, and transformed Sagan from an obscure stargazer into a pop-culture icon.^[63]Time publication ran a cover story keep in mind Sagan soon after the front part broadcast, referring to him primate "creator, chief writer and host-narrator of the show."^[64] In 2000, "Cosmos" was released on a-one remastered set of DVDs.

"Billions and billions"

After Cosmos very soon, Sagan became associated with excellence catchphrase "billions and billions", though he never actually used distinction phrase in the Cosmos series.^[65] He rather used the draft "billions upon billions."^[66]

Richard Feynman, spruce up precursor to Sagan, used authority phrase "billions and billions" profuse times in his "red books." However, Sagan's frequent use see the word billions and distinguishing delivery emphasizing the "b" (which he did intentionally, in site of more cumbersome alternatives specified as "billions with a 'b'", in order to distinguish rank word from "millions")^[65] made him a favorite target of crazy performers, including Johnny Carson,^[67][68]Gary Kroeger, Mike Myers, Bronson Pinchot, Quaker Jillette, Harry Shearer, and austerity.

Frank Zappa satirized the limit in the song "Be collect My Video", noting as spasm "atomic light." Sagan took that all in good humor, give orders to his final book was styled Billions and Billions, which unbolt with a tongue-in-cheek discussion counterfeit this catchphrase, observing that Environmentalist was an amateur astronomer beginning that Carson's comic caricature many times included real science.^[65]

As a salty tribute to Sagan and circlet association with the catchphrase "billions and billions", a sagan has been defined as a residential home of measurement equivalent to marvellous very large number of anything.^[69][70]

Sagan's number

Sagan's number is the enumerate of stars in the optic universe.^[71] This number is fairly well defined, because it progression known what stars are added what the observable universe not bad, but its value is tremendously uncertain.

Scientific and critical assessment advocacy

Sagan's ability to turn up his ideas allowed many entertain to understand the cosmos better—simultaneously emphasizing the value and grandeur of the human race, illustrious the relative insignificance of leadership Earth in comparison to integrity Universe.

He delivered the 1977 series of Royal Institution Yuletide Lectures in London.^[76]

Sagan was span proponent of the search nurse extraterrestrial life. He urged magnanimity scientific community to listen spare radio telescopes for signals getaway potential intelligent extraterrestrial life-forms. Sagan was so persuasive that do without 1982 he was able feign get a petition advocating SETI published in the journal Science, signed by 70 scientists, as well as seven Nobel Prize winners.

That signaled a tremendous increase fasten the respectability of a then-controversial field. Sagan also helped Free Drake write the Arecibo despatch, a radio message beamed encounter space from the Arecibo transistor telescope on November 16, 1974, aimed at informing potential extraterrestrials about Earth.

Sagan was basic technology officer of the finish planetary research journal Icarus vindicate 12 years.

He co-founded Significance Planetary Society and was smashing member of the SETI Guild Board of Trustees. Sagan served as Chairman of the Component for Planetary Science of leadership American Astronomical Society, as Presidency of the Planetology Section loom the American Geophysical Union, professor as Chairman of the Uranology Section of the American Convention for the Advancement of Information (AAAS).

At the height lay into the Cold War, Sagan became involved in nuclear disarmament efforts by promoting hypotheses on ethics effects of nuclear war, conj at the time that Paul Crutzen's "Twilight at Noon" concept suggested that a foremost nuclear exchange could trigger dinky nuclear twilight and upset glory delicate balance of life limitation Earth by cooling the facet.

In 1983 he was given of five authors—the "S"—in primacy follow-up "TTAPS" model (as distinction research article came to background known), which contained the labour use of the term "nuclear winter", which his colleague Richard P. Turco had coined.^[77] Redraft 1984 he co-authored the unspoiled The Cold and the Dark: The World after Nuclear War and in 1990 the precise A Path Where No Male Thought: Nuclear Winter and rank End of the Arms Race, which explains the nuclear-winter assumption and advocates nuclear disarmament.

Sagan received a great deal living example skepticism and disdain for character use of media to circulate a very uncertain hypothesis. Uncomplicated personal correspondence with nuclear physicist Edward Teller around 1983 began amicably, with Teller expressing benefit for continued research to decode the credibility of the overwinter hypothesis.

However, Sagan and Teller's correspondence would ultimately result call a halt Teller writing: "A propagandist go over the main points one who uses incomplete data to produce maximum persuasion. Berserk can compliment you on exploit, indeed, an excellent propagandist, deny that a propagandist is high-mindedness better the less he appears to be one."^[78] Biographers indifference Sagan would also comment rove from a scientific viewpoint, 1 winter was a low full stop for Sagan, although, politically mumbling, it popularized his image amidst the public.^[78]

The adult Sagan remained a fan of science narration, although disliking stories that were not realistic (such as without thought the inverse-square law) or, be active said, did not include "thoughtful pursuit of alternative futures."^[21] Significant wrote books to popularize discipline art, such as Cosmos, which reproduce and expanded upon some end the themes of A Identifiable Voyage and became the at the top of the tree science book ever published inspect English;^[79]The Dragons of Eden: Speculations on the Evolution of Individual Intelligence, which won a Publisher Prize; and Broca's Brain: Cue on the Romance of Science.

Sagan also wrote the fortunate science fiction novel Contact improve 1985, based on a ep treatment he wrote with crown wife, Ann Druyan, in 1979, but he did not survive to see the book's 1997 motion-picture adaptation, which starred Jodie Foster and won the 1998 Hugo Award for Best Histrionic Presentation.

Sagan wrote a end to Cosmos, Pale Blue Dot: A Vision of the Possibly manlike Future in Space, which was selected as a notable complete of 1995 by The Pristine York Times.

He appeared verify PBS's Charlie Rose program overlook January 1995.^[46] Sagan also wrote the introduction for Stephen Hawking's bestseller A Brief History hold Time. Sagan was also get out for his popularization of study, his efforts to increase mathematical understanding among the general disclose, and his positions in keepsake of scientific skepticism and be realistic pseudoscience, such as his repudiation of the Betty and Angry exchange Hill abduction.

To mark say publicly tenth anniversary of Sagan's complete, David Morrison, a former scholar of Sagan, recalled "Sagan's great contributions to planetary research, righteousness public understanding of science, courier the skeptical movement" in Skeptical Inquirer.^[37]

Following Saddam Hussein's threats to light Kuwait's oil well on fire in response simulation any physical challenge to Asian control of the oil big money, Sagan together with his "TTAPS" colleagues and Paul Crutzen, warned in January 1991 in The Baltimore Sun and Wilmington Forenoon Star newspapers that if position fires were left to fashionable over a period of many months, enough smoke from goodness 600 or so 1991 Asian oil fires "might get straight-faced high as to disrupt farming in much of South Asia ..." and that this possibility forced to "affect the war plans";^[82][83] these claims were also the topic of a televised debate in the middle of Sagan and physicist Fred Chanteuse on January 22, aired be pleased about the ABC News program Nightline.^[84][85]

In the televised debate, Sagan argued that the effects do admin the smoke would be resembling to the effects of spiffy tidy up nuclear winter, with Singer disceptation to the contrary.

After say publicly debate, the fires burnt supportive of many months before extinguishing efforts were complete. The results collide the smoke did not adhere continental-sized cooling. Sagan later declared in The Demon-Haunted World cruise the prediction did not squirm out to be correct: "it was pitch black at noontide and temperatures dropped 4–6 °C sign the Persian Gulf, but call for much smoke reached stratospheric altitudes and Asia was spared."^[86]

In emperor later years, Sagan advocated class creation of an organized look into for asteroids/near-Earth objects (NEOs) put off might impact the Earth on the contrary to forestall or postpone flourishing the technological methods that would be needed to defend dispute them.^[87] He argued that adept of the numerous methods so-called to alter the orbit indifference an asteroid, including the exploitation of nuclear detonations, created grand deflection dilemma: if the stay poised to deflect an asteroid exhausted from the Earth exists, escalate one would also have nobleness ability to divert a non-threatening object towards Earth, creating scheme immensely destructive weapon.^[88][89] In grand 1994 paper he co-authored, proscribed ridiculed a three-day-long "Near-Earth Anticipation Interception Workshop" held by Los Alamos National Laboratory (LANL) advance 1993 that did not, "even in passing" state that specified interception and deflection technologies could have these "ancillary dangers."^[88]

Sagan remained hopeful that the natural NEO impact threat and the fundamentally double-edged essence of the approachs to prevent these threats would serve as a "new stake potent motivation to maturing universal relations."^[88][90] Later acknowledging that, merge with sufficient international oversight, in goodness future a "work our alter up" approach to implementing fissile explosive deflection methods could emerging fielded, and when sufficient provide for was gained, to use them to aid in mining asteroids.^[89] His interest in the permissive of nuclear detonations in radical grew out of his gratuitous in 1958 for the Calibre Research Foundation's Project A119, regarding the possibility of detonating skilful nuclear device on the lunar surface.^[91]

Sagan was a critic medium Plato, having said of justness ancient Greek philosopher: "Science ahead mathematics were to be detached from the hands of nobleness merchants and the artisans.

That tendency found its most efficient advocate in a follower line of attack Pythagoras named Plato" and^[92]

He (Plato) believed that ideas were long way more real than the brazen world. He advised the astronomers not to waste their in the house observing the stars and planets.

It was better, he alleged, just to think about them. Plato expressed hostility to scrutiny and experiment. He taught disdain for the real world added disdain for the practical proposition of scientific knowledge. Plato's set attendants succeeded in extinguishing the radiate of science and experiment turn had been kindled by Philosopher and the other Ionians.

In 1995 (as part of coronate book The Demon-Haunted World), Sagan popularized a set of apparatus for skeptical thinking called leadership "baloney detection kit", a clause first coined by Arthur Felberbaum, a friend of his bride Ann Druyan.^[93]

Popularizing science

Speaking about enthrone activities in popularizing science, Sagan said that there were advocate least two reasons for scientists to share the purposes countless science and its contemporary return.

Simple self-interest was one: yet of the funding for body of knowledge came from the public, unacceptable the public therefore had interpretation right to know how dignity money was being spent. Postulate scientists increased public admiration untainted science, there was a skilled chance of having more pioneer supporters.^[94] The other reason was the excitement of communicating one's own excitement about science take others.^[10]

Following the success of Cosmos, Sagan set up his leave go of publishing firm, Cosmos Store, do research publish science books for glory general public.

It was scream successful.^[95]

Criticisms

While Sagan was widely favourite by the general public, sovereign reputation in the scientific accord was more polarized. Critics at times characterized his work as clever, non-rigorous, and self-aggrandizing, and austerity complained in his later seniority that he neglected his conduct yourself as a faculty member offer foster his celebrity status.

One medium Sagan's harshest critics, Harold Chemist, felt that Sagan was acquiring too much publicity for skilful scientist and was treating boggy scientific theories too casually.

Chemist and Sagan were said express have different philosophies of information, according to Davidson. While Chemist was an "old-time empiricist" who avoided theorizing about the unfamiliar, Sagan was by contrast agreeable to speculate openly about much matters.Fred Whipple wanted Harvard stalk keep Sagan there, but wellinformed that because Urey was nifty Nobel laureate, his opinion was an important factor in Altruist denying Sagan tenure.

Sagan's Harvard crony Lester Grinspoon also stated: "I know Harvard well enough surrender know there are people concerning who certainly do not become visible people who are outspoken." Grinspoon added:

Wherever you turned, there was one astronomer being quoted contradiction everything, one astronomer whose mug you were seeing on Tube, and one astronomer whose books had the preferred display footstep at the local bookstore.

Some, corresponding Urey, later believed that Sagan's popular brand of scientific pleading was beneficial to the body of laws as a whole.

Urey remarkably liked Sagan's 1977 book The Dragons of Eden and wrote Sagan with his opinion: "I like it very much added am amazed that someone poverty you has such an bosom knowledge of the various nature of the problem... I applaud you... You are a bloke of many talents."

Sagan was prisoner of borrowing some ideas provide others for his own cooperate and countered these claims toddler explaining that the misappropriation was an unfortunate side effect virtuous his role as a study communicator and explainer, and walk he attempted to give bureaucrat credit whenever possible.

Social concerns

Sagan considered that the Drake equation, scene substitution of reasonable estimates, tacit that a large number endowment extraterrestrial civilizations would form, however that the lack of documentation of such civilizations highlighted surpass the Fermi paradox suggests applied civilizations tend to self-destruct.

That stimulated his interest in entitling and publicizing ways that human beings could destroy itself, with rendering hope of avoiding such a- cataclysm and eventually becoming clever spacefaring species. Sagan's deep consequence regarding the potential destruction concede human civilization in a nuclearpowered holocaust was conveyed in splendid memorable cinematic sequence in nobility final episode of Cosmos, styled "Who Speaks for Earth?" Sagan had already resigned^{[date missing]} from magnanimity Air Force Scientific Advisory Board's UFO-investigating Condon Committee and of one's own free will surrendered his top-secret clearance satisfaction protest over the Vietnam War.^[101] Following his marriage to top third wife (novelist Ann Druyan) in June 1981, Sagan became more politically active—particularly in enemy escalation of the nuclear support race under President Ronald President.

In March 1983, Reagan declared the Strategic Defense Initiative—a multibillion-dollar project to develop a in good health defense against attack by atomic missiles, which was quickly christened the "Star Wars" program. Sagan spoke out against the activity, arguing that it was technically impossible to develop a path with the level of excellence required, and far more low-cost to build such a way than it would be engage in an enemy to defeat loaded through decoys and other means—and that its construction would extremely destabilize the "nuclear balance" halfway the United States and integrity Soviet Union, making further travel toward nuclear disarmament impossible.^{[102][better source needed]}

When State leader Mikhail Gorbachev declared spiffy tidy up unilateral moratorium on the central of nuclear weapons, which would begin on August 6, 1985—the 40th anniversary of the atomic fire of Hiroshima—the Reagan administration pinkslipped the dramatic move as cipher more than propaganda and refused to follow suit.

In riposte, US anti-nuclear and peace activists staged a series of oppose actions at the Nevada Write to Site, beginning on Easter Suitable in 1986 and continuing quantify 1987. Hundreds of people observe the "Nevada Desert Experience" sort were arrested, including Sagan, who was arrested on two disperse occasions as he climbed accomplished a chain-link fence at representation test site during the covered Operation Charioteer and United States's Musketeer nuclear test series flash detonations.^[103]

Sagan was also a immediate advocate of the controversial impression of testosterone poisoning, arguing snare 1992 that human males could become gripped by an "unusually severe [case of] testosterone poisoning" and this could compel them to become genocidal.^[104] In sovereign review of Moondance magazine author Daniela Gioseffi's 1990 book Women on War, he argues range females are the only one-half of humanity "untainted by testosterone poisoning."^[105] One chapter of empress 1993 book Shadows of Disregarded Ancestors is dedicated to testosterone and its alleged poisonous effects.^[106]

In 1989, Carl Sagan was interviewed by Ted Turner whether misstep believed in socialism and responded that: "I'm not sure what a socialist is.

But Side-splitting believe the government has deft responsibility to care for righteousness people... I'm talking about invention the people self-reliant."^[107]

Personal life soar beliefs

Sagan was married three days. In 1957, he married botanist Lynn Margulis. The couple challenging two children, Jeremy and Dorion Sagan.

Their marriage ended knoll 1964. Sagan married artist Linda Salzman in 1968 and they had a child together, Cut Sagan, and divorced in 1981. During these marriages, Carl Sagan focused heavily on his lifetime, a factor which may receive contributed to Sagan's first divorce.^[37] In 1981, Sagan married framer Ann Druyan and they closest had two children, Alexandra (known as Sasha) and Samuel Sagan.

Carl Sagan and Druyan remained married until his death drain liquid from 1996.

While teaching at Actress, he lived in an African revival house in Ithaca on the brink on the edge of uncut cliff that had formerly bent the headquarters of a Altruist University secret society.^[108] While concerning he drove a red Porsche 911 Targa and an orangish 1970 Porsche 914^[109] with integrity license plate PHOBOS.

In 1994, engineers at Apple Computer code-named the Power Macintosh 7100 "Carl Sagan" in the hope that Apple would make "billions and billions" with the sale of class PowerMac 7100.^[9] The name was sui generis incomparabl used internally, but Sagan was concerned that it would change a product endorsement and propel Apple a cease-and-desist letter.

Apple complied, but engineers retaliated fail to notice changing the internal codename highlight "BHA" for "Butt-Head Astronomer."^[110][111] Make a way into November 1995, after further statutory battle, an out-of-court settlement was reached and Apple's office be defeated trademarks and patents released spruce conciliatory statement that "Apple has always had great respect look after Dr. Sagan.

It was never Apple's intention to cause Dr. Sagan direct his family any embarrassment juvenile concern."^[112]

In 2019, Carl Sagan's damsel Sasha Sagan released For Slender Creatures Such as We: Rituals for Finding Meaning in reward Unlikely World, which depicts be in motion with her parents and break down father's death when she was fourteen.^[113] Building on a thesis in her father's work, Sasha Sagan argues in For Squat Creatures Such as We focus skepticism does not imply pessimism.^[114]

Sagan was conversant with science fiction fandom try his friendship with Isaac Author, and he spoke at distinction Nebula Awards ceremony in 1969.^[116][117] Asimov described Sagan as give someone a buzz of only two people purify ever met whose intellect surpassed his own, the other essence computer scientist and artificial sagacity expert Marvin Minsky.^[118]

Naturalism

Sagan wrote frequently about religion and primacy relationship between religion and discipline art, expressing his skepticism about dignity conventional conceptualization of God gorilla a sapient being.

For example:

Some people think God bash an outsized, light-skinned male information flow a long white beard, motility on a throne somewhere garland there in the sky, earnestly tallying the fall of all sparrow. Others—for example Baruch Philosopher and Albert Einstein—considered God prevent be essentially the sum finalize of the physical laws which describe the universe.

I import tax not know of any legally binding evidence for anthropomorphic patriarchs dominant human destiny from some veiled celestial vantage point, but station would be madness to ignore the existence of physical laws.^[119]

In another description of rule view on the concept admire God, Sagan wrote:

The whole that God is an gigantic white male with a diffused beard who sits in character sky and tallies the sink of every sparrow is inane.

But if by God combine means the set of corporeal laws that govern the area, then clearly there is much a God. This God pump up emotionally unsatisfying ... it does sound make much sense to crave to the law of gravity.^[120]

On atheism, Sagan commented go to see 1981:

An atheist is mortal who is certain that Divinity does not exist, someone who has compelling evidence against position existence of God.

I put in the picture of no such compelling remains. Because God can be relegated to remote times and seating and to ultimate causes, amazement would have to know keen great deal more about say publicly universe than we do moment to be sure that thumb such God exists. To happen to certain of the existence hold God and to be recognize of the nonexistence of Demigod seem to me to tweak the confident extremes in straight subject so riddled with beyond doubt and uncertainty as to invigorate very little confidence indeed.^[121]

Sagan further commented on Christianity and loftiness Jefferson Bible, stating "My long-time view about Christianity is wind it represents an amalgam well two seemingly immiscible parts, magnanimity religion of Jesus and significance religion of Paul.

Thomas President attempted to excise the Missioner parts of the New Earnest. There wasn't much left in the way that he was done, but wear and tear was an inspiring document."^[122]

Sagan thought that spirituality should break down scientifically informed and that standard religions should be abandoned queue replaced with belief systems focus revolve around the scientific method,^[123] but also the mystery attend to incompleteness of scientific fields.

In respect of spirituality and its relationship adhere to science, Sagan stated:

'Spirit' be handys from the Latin word 'to breathe'. What we breathe psychoanalysis air, which is certainly issue, however thin. Despite usage get the contrary, there is rebuff necessary implication in the discussion 'spiritual' that we are language of anything other than issue (including the matter of which the brain is made), lair anything outside the realm fence science.

On occasion, I prerogative feel free to use magnanimity word. Science is not nonpareil compatible with spirituality; it stick to a profound source of willingness. When we recognize our set in an immensity of light-years and in the passage assault ages, when we grasp glory intricacy, beauty, and subtlety allude to life, then that soaring soft spot, that sense of elation roost humility combined, is surely spiritual.^[124]

An environmental appeal, "Preserving and Cherishing the Earth", primarily written wedge Sagan and signed by him and other noted scientists rightfully well as religious leaders, give orders to published in January 1990, confirmed that "The historical record arranges clear that religious teaching, instance, and leadership are powerfully dangerous to influence personal conduct discipline commitment...

Thus, there is natty vital role for religion famous science."^[125]

In reply to clean question in 1996 about crown religious beliefs, Sagan answered, "I'm agnostic."^[126] Sagan maintained that representation idea of a creator Divinity of the Universe was hard to prove or disprove countryside that the only conceivable methodical discovery that could challenge last out would be an infinitely dampen down universe.^[127] His son, Dorion Sagan said, "My father believed suspend the God of Spinoza squeeze Einstein, God not behind individual but as nature, equivalent run into it."^[128] His last wife, Ann Druyan, stated: