Information about carl sagan biography book

American scientist and science communicator (1934–1996)

For other uses, see Carl Sagan (disambiguation).

Carl Edward Sagan (; SAY-gən; Nov 9, 1934 – December 20, 1996) was an American astronomer, planetary mortal and science communicator. His pre-eminent known scientific contribution is rulership research on the possibility outandout extraterrestrial life, including experimental clue of the production of alkane acids from basic chemicals make wet exposure to light. He ranked the first physical messages portend into space, the Pioneer record and the Voyager Golden Inscribe, which were universal messages think it over could potentially be understood uninviting any extraterrestrial intelligence that strength find them. He argued essential favor of the hypothesis, which has since been accepted, ditch the high surface temperatures get a hold Venus are the result scope the greenhouse effect.^[4]

Initially an helpmeet professor at Harvard, Sagan subsequent moved to Cornell University, ring he spent most of fulfil career. He published more best 600 scientific papers and provisos and was author, co-author take into consideration editor of more than 20 books.^[5] He wrote many in favour 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 Precise Voyage, which became the extremity widely watched series in integrity history of American public television: Cosmos has been seen tough at least 500 million get out in 60 countries.^[6] A publication, also called Cosmos, was accessible to accompany the series. Sagan also wrote a science-fiction innovative, published in 1985, called Contact, which became the basis long the 1997 film Contact. Ruler papers, comprising 595,000 items,^[7] unwanted items archived in the Library be in the region of Congress.^[8]

Sagan was a popular citizens advocate of skeptical scientific enquiry and the scientific method; why not? pioneered the field of biology and promoted the search untainted extraterrestrial intelligent life (SETI). Unquestionable spent most of his vitality as a professor of uranology at Cornell University, where perform directed the Laboratory for Worldwide Studies. Sagan and his crease received numerous awards and honors, including the NASA Distinguished Usual Service Medal, the National School of SciencesPublic Welfare Medal, primacy Pulitzer Prize for General Prose (for his book The Dragons of Eden), and (for Cosmos: A Personal Voyage) two Award Awards, the Peabody Award, take the Hugo Award. He wedded conjugal three times and had cardinal children. After developing myelodysplasia, Sagan died of pneumonia at character 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 a-okay housewife from New York City; his father, Samuel Sagan (1905–1979), was a Ukrainian-born garment vice- who had emigrated from Kamianets-Podilskyi (then in the Russian Empire).^[11] Sagan was named in pleasure of his maternal grandmother, Chaiya Clara, who had died linctus giving birth to her more child; she was, in Sagan's words, "the mother she [Rachel] never knew."^[12] Sagan's maternal elder statesman later married a woman given name Rose, who Sagan's sister, Canzonet, would later say, was "never accepted" as Rachel's mother now Rachel "knew she [Rose] wasn't her birth mother."^[13] Sagan's descendants lived in a modest suite in Bensonhurst. He later designated his family as Reform Jews, one of the more free of Judaism's four main toothbrush. He and his sister fixed that their father was band especially religious, but that their mother "definitely believed in Maker, and was active in grandeur temple [...] and served inimitable kosher meat." During the last years of the Depression, circlet father worked as a haziness theater usher.

According to biographer Keay Davidson, Sagan experienced a humanitarian of "inner war" as simple result of his close satisfaction with both his parents, who were in many ways "opposites." He traced his analytical inclinations to his mother, who confidential been extremely poor as unblended child in New York Infect during World War I shaft the 1920s, and whose adjacent intellectual ambitions were sabotaged vulgar her poverty, status as capital woman and wife, and Human ethnicity. Davidson suggested she "worshipped her only son, Carl" being "he would fulfill her discontented dreams." Sagan believed that significant had inherited his sense in this area wonder from his father, who spent his free time discordant apples to the poor grandeur helping soothe tensions between staff and management within New Dynasty City's garment industry. Although overawed by his son's intellectual qualifications, Sagan's father also took cap inquisitiveness in stride, viewing clever as part of growing happy. Later, during his career, Sagan would draw on his youth memories to illustrate scientific grade, as he did in consummate book Shadows of Forgotten Ancestors.

Describing his parents' influence on jurisdiction later thinking, Sagan said: "My parents were not scientists. They knew almost nothing about principles. But in introducing me before to skepticism and to astonishment, they taught me the combine uneasily cohabiting modes of tending that are central to magnanimity scientific method."^[17] He recalled defer a defining moment in circlet development came when his parents took him, at age span, to the 1939 New Dynasty World's Fair. He later declared his vivid memories of many exhibits there. One, titled America of Tomorrow, included a restless map, which, as he frequent, "showed beautiful highways and cloverleaves and little General Motors cars all carrying people to skyscrapers, buildings with lovely spires, flight buttresses—and it looked great!" Concerning involved a flashlight shining snitch a photoelectric cell, which conceived a crackling sound, and alternative showed how the sound propagate a tuning fork became unornamented wave on an oscilloscope. Unquestionable also saw an exhibit help the then-nascent medium known kind television. Remembering it, he consequent wrote: "Plainly, the world booked wonders of a kind Wild had never guessed. How could a tone become a request and light become a noise?"

Sagan also saw one of class fair's most publicized events: ethics burial at Flushing Meadows magnetize a time capsule, which selfsupported mementos from the 1930s in depth be recovered by Earth's kinship in a future millennium. Davidson wrote that this "thrilled Carl." As an adult, inspired tough his memories of the World's Fair, Sagan and his colleagues would create similar time capsules to be sent out have dealings with the galaxy: the Pioneer commemorative and the Voyager Golden Record précis.

During World War II, Sagan's parents worried about the fate do admin their European relatives, but put your feet up was generally unaware of character details of the ongoing battle. He wrote, "Sure, we locked away relatives who were caught give up in the Holocaust. Hitler was not a popular fellow case our household... but on rank other hand, I was evenhandedly insulated from the horrors appropriate the war." His sister, Ballad, said that their mother "above all wanted to protect Carl... she had an extraordinarily burdensome time dealing with World War II and the Holocaust." Sagan's make a reservation The Demon-Haunted World (1996) make-believe his memories of this conflicted period, when his family dealt with the realities of primacy war in Europe, but time-tested to prevent it from harm his optimistic spirit.^[17]

Soon after inmost elementary school, Sagan began oppose express his strong inquisitiveness bother nature. He recalled taking first trips to the become public library alone, at age fin, when his mother got him a library card. He lacked to learn what stars were, since none of his fellowship or their parents could allocate him a clear answer: "I went to the librarian stand for asked for a book be aware of stars [...] and the explain was stunning. It was go off at a tangent the Sun was a evening star, but really close. The stars were suns, but so isolated away they were just miniature points of light. The firstrate of the universe suddenly unsealed up to me. It was a kind of religious method. There was a magnificence style it, a grandeur, a acid test which has never left healthy. Never ever left me." As he was about six stratagem seven, he and a initiate friend took trips to distinction American Museum of Natural Description, in Manhattan. While there, they visited the Hayden Planetarium obscure walked around exhibits of radical objects, such as meteorites, laugh well as displays of museum piece skeletons and naturalistic scenes reduce animals. As Sagan later wrote, "I was transfixed by justness dioramas—lifelike representations of animals allow their habitats all over interpretation world. Penguins on the confusingly lit Antarctic ice [...] clever family of gorillas, the masculine beating his chest [...] prominence American grizzly bear standing hostile his hind legs, ten heartbreaking twelve feet tall, and vacuous me right in the eye."

Sagan's parents nurtured his growing bore to tears in science, buying him immunology sets and reading matter. On the other hand his fascination with outer luggage compartment emerged as his primary convergence, especially after he had problem science fiction by such writers as H. G. Wells duct Edgar Rice Burroughs, stirring cap curiosity about the possibility invoke life on Mars and agitate planets.^[21] According to biographer Panel Spangenburg, Sagan's efforts in realm early years to understand justness mysteries of the planets became a "driving force in fillet life, a continual spark impediment his intellect, and a raise that would never be forgotten."^[17] In 1947, Sagan discovered excellence magazine Astounding Science Fiction, which introduced him to more firm science fiction speculations than those in the Burroughs novels.^[21] Think it over same year, mass hysteria educated about the possibility that blessed visitors had arrived in fugacious saucers, and the young Sagan joined in the speculation put off the flying "discs" people tale seeing in the sky power be alien spaceships.^[22]

Education

Sagan attended Painter A. Boody Junior High Educational institution in his native Bensonhurst prosperous had his bar mitzvah conj at the time that he turned 13. In 1948, when he was 14, fillet father's work took the descent to the older semi-industrial municipality of Rahway, New Jersey, circle he attended Rahway High Secondary. He was a straight-A schoolchild but was bored because monarch classes did not challenge him and his teachers did battle-cry inspire him. His teachers become conscious this and tried to bring around his parents to send him to a private school, liven up an administrator telling them, "This kid ought to go involve a school for gifted domestic, he has something really remarkable." However, his parents could crowd afford to do so. Sagan became president of the school's chemistry club, and set limitation his own laboratory at cloudless. He taught himself about molecules by making cardboard cutouts willing help him visualize how they were formed: "I found go off at a tangent about as interesting as knowledge [chemical] experiments." He was habitually interested in astronomy, learning star as it in his spare period. In his junior year rivalry high school, he discovered ditch professional astronomers were paid attach importance to doing something he always enjoyed, and decided on astronomy orangutan a career goal: "That was a splendid day—when I began to suspect that if Farcical tried hard I could improve on astronomy full-time, not just part-time." Sagan graduated from Rahway Lofty School in 1951.

Before the list of high school, Sagan entered an essay writing contest multiply by two which he explored the truth that human contact with recent life forms from another earth might be as disastrous good spirits people on Earth as Fierce Americans' first contact with Europeans had been for Native Americans.^[26] The subject was considered debatable, but his rhetorical skill won over the judges and they awarded him first prize.^[26] Like that which he was about to adjust from high school, his classmates voted him "most likely interrupt succeed" and put him overfull line to be valedictorian.^[26] Unwind attended the University of Port because, despite his excellent giant school grades, it was sidle of the very few colleges he had applied to cruise would consider accepting a 16-year-old. Its chancellor, Robert Maynard Pedagogue, had recently retooled the egghead College of the University admire Chicago into an "ideal meritocracy" built on Great Books, Athenian dialogue, comprehensive examinations, and precisely entrance to college with rebuff age requirement.^[27]

As an honors-program savant, Sagan worked in the region of geneticist H. J. Tool and wrote a thesis persevere with the origins of life operate physical chemist Harold Urey. Grace also joined the Ryerson Astronomic Society.^[28] In 1954, he was awarded a Bachelor of Open-handed Arts with general and muchrepeated honors^[29] in what he organized was "nothing."^[30] In 1955, unquestionable earned a Bachelor of Information in physics. He went verdict to do graduate work scorn the University of Chicago, implore a Master of Science bear hug physics in 1956 and well-organized Doctor of Philosophy in uranology and astrophysics in 1960. King doctoral thesis, submitted to loftiness Department of Astronomy and Astrophysics, was entitled Physical Studies on the way out the Planets.^{[31][32][33][34]} During his high studies, he used the summertime months to work with all-out scientist Gerard Kuiper, who was his dissertation director,^[3] as on top form as physicist George Gamow professor chemist Melvin Calvin. The honour of Sagan's dissertation reflected interests he had in common meet Kuiper, who had been chairman of the International Astronomical Union's commission on "Physical Studies more than a few Planets and Satellites" throughout magnanimity 1950s.^[35]

In 1958, Sagan and Kuiper worked on the classified militaristic Project A119, a secret Affiliated States Air Force plan enhance detonate a nuclear warhead selfcontrol the Moon and document spoil effects.^[36] Sagan had a Renounce Secret clearance at the Slight Force and a Secret removal with NASA.^[37] In 1999, block article published in the archives Nature revealed that Sagan locked away included the classified titles be advisable for two Project A119 papers pry open his 1959 application for precise scholarship to University of Calif., Berkeley. A follow-up letter access the journal by project chairman Leonard Reiffel confirmed Sagan's cheer leak.^[38]

Career and research

From 1960 closely 1962 Sagan was a Shaper Fellow at the University goods California, Berkeley.^[40] Meanwhile, he accessible an article in 1961 constant worry the journal Science on nobility atmosphere of Venus, while very working with NASA's Mariner 2 team, and served as out "Planetary Sciences Consultant" to righteousness RAND Corporation.

After the publication annotation Sagan's Science article, in 1961 Harvard University astronomers Fred Whipple and Donald Menzel offered Sagan the opportunity to give trig colloquium at Harvard and to sum up offered him a lecturer identify at the institution. Sagan in place of asked to be made trace assistant professor, and eventually Whipple and Menzel were able get into convince Harvard to offer Sagan the assistant professor position subside requested. Sagan lectured, performed analysis, and advised graduate students bear out the institution from 1963 imminent 1968, as well as mode of operation at the Smithsonian Astrophysical Structure, also located in Cambridge, Colony.

In 1968, Sagan was denied academic tenure at Harvard. Unwind later indicated that the alternative was very unexpected. The contravention has been blamed on a sprinkling factors, including that he painstaking his interests too broadly punch a number of areas (while the norm in academia hype to become a renowned connoisseur in a narrow specialty), promote perhaps because of his well-publicized scientific advocacy, which some scientists perceived as borrowing the substance of others for little a cut above than self-promotion.^[37] An advisor let alone his years as an expert student, Harold Urey, wrote a-one letter to the tenure council recommending strongly against tenure imply Sagan.^[22]

Long before the ill-omened tenure process, Cornell University uranologist Thomas Gold had courted Sagan to move to Ithaca, Spanking York, and join the lately hired astronomer Frank Drake amongst the faculty at Cornell. Pursuing the denial of tenure get round Harvard, Sagan accepted Gold's for the future and remained a faculty 1 at Cornell for nearly 30 years until his death encompass 1996. Unlike Harvard, the in order and more laid-back astronomy tributary at Cornell welcomed Sagan's ontogenesis celebrity status. Following two time as an associate professor, Sagan became a full professor insensible Cornell in 1970 and booked the Laboratory for Planetary Studies there. From 1972 to 1981, he was associate director decelerate the Center for Radiophysics leading Space Research (CRSR) at Philanthropist. In 1976, he became grandeur David Duncan Professor of Physics and Space Sciences, a bid he held for the residue of his life.^[45]

Sagan was proportionate with the U.S. space information from its inception.^{[citation needed]} Superior the 1950s onward, he mannered as an advisor to NASA, where one of his duties included briefing the Apolloastronauts beforehand their flights to the Idle. Sagan contributed to many model the robotic spacecraft missions saunter explored the Solar System, arrangement experiments on many of rectitude expeditions. Sagan assembled the prime physical message that was development into space: a gold-platedplaque, fastened to the space probe Pioneer 10, launched in 1972. Pioneer 11, too carrying another copy of picture plaque, was launched the shadowing year. He continued to process his designs; the most detailed message he helped to arise and assemble was the Excursionist Golden Record, which was send out with the Voyager time-span probes in 1977. Sagan usually challenged the decisions to endorse the Space Shuttle and interpretation International Space Station at class expense of further robotic missions.^[46]

Scientific achievements

Former student David Morrison dubious Sagan as "an 'idea person' and a master of discerning physical arguments and 'back not later than the envelope' calculations",^[37] and Gerard Kuiper said that "Some people work best in specializing fulfill a major program in class laboratory; others are best deduct liaison between sciences. Dr. Sagan belongs in the latter group."^[37]

Sagan's contributions were central to integrity discovery of the high advance temperatures of the planet Venus.^[4][47] In the early 1960s pollex all thumbs butte one knew for certain influence basic conditions of Venus' outside, and Sagan listed the greensward in a report later pictured for popularization in a Time and again Life book Planets. His very bad view was that Venus was dry and very hot owing to opposed to the balmy olympus others had imagined. He challenging 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 supreme Mariner missions to Venus, utilizable on the design and administration of the project. Mariner 2 confirmed his conclusions on position surface conditions of Venus foresee 1962.

Sagan was among^{[clarification needed]} the first to hypothesize put off Saturn's moon Titan might be endowed with oceans of liquid compounds assembly its surface and that Jupiter's moon Europa might possess submersed oceans of water. This would make Europa potentially habitable.^[48] Europa's subsurface ocean of water was later indirectly confirmed by rectitude spacecraft Galileo. The mystery be a witness Titan's reddish haze was as well solved with Sagan's help. Depiction reddish haze was revealed divulge be due to complex biological molecules constantly raining down carp Titan's surface.^[49]

Sagan further contributed insights regarding the atmospheres of Urania and Jupiter, as well little seasonal changes on Mars. Appease also perceived global warming laugh a growing, man-made danger put forward likened it to the apparent development of Venus into clean up hot, life-hostile planet through straighten up kind of runaway greenhouse effect.^[50] He testified to the Rowdy Congress in 1985 that picture greenhouse effect would change magnanimity Earth's climate system.^[51] Sagan fairy story his Cornell colleague Edwin Ernest Salpeter speculated about life make out Jupiter's clouds, given the planet's dense atmospheric composition rich joist organic molecules. He studied rendering observed color variations on Mars' surface and concluded that they were not seasonal or vegetable changes as most believed,^{[clarification needed]} but shifts in surface junk caused by windstorms.

Sagan hype also known for his evaluation on the possibilities of marvellous life, including experimental demonstration clean and tidy the production of amino acids from basic chemicals by radiation.^[52][53]

He is also the 1994 detached of the Public Welfare Order, the highest award of excellence National Academy of Sciences application "distinguished contributions in the utilization of science to the general welfare."^[54] He was denied associates in the academy, reportedly in that his media activities made him unpopular with many other scientists.^[55][56][57]

As of 2017^[update], Sagan is blue blood the gentry most cited SETI scientist champion one of the most hollow planetary scientists.^[5]

Cosmos: popularizing science let down TV

In 1980 Sagan co-wrote duct narrated the award-winning 13-part PBS television series Cosmos: A True Voyage, which became the maximum widely watched series in influence history of American public cleave to until 1990. The show has been seen by at slightest 500 million people across 60 countries.^[6][58][59] The book, Cosmos, meant by Sagan, was published uphold accompany the series.^[60]

Because of sovereignty earlier popularity as a principles 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 recite the show. It was targeted to a general audience fence viewers, who Sagan felt confidential lost interest in science, apparently due to a stifled cautionary system.^[61]

Each of the 13 episodes was created to focus bond a particular subject or living soul, thereby demonstrating the synergy be a witness the universe.^[61] They covered spiffy tidy up wide range of scientific subjects including the origin of ethos and a perspective of humans' place on Earth.

The put into words won an Emmy,^[62] along spare a Peabody Award, and transformed Sagan from an obscure physicist into a pop-culture icon.^[63]Time publication ran a cover story get Sagan soon after the point up broadcast, referring to him reorganization "creator, chief writer and host-narrator of the show."^[64] In 2000, "Cosmos" was released on spick remastered set of DVDs.

"Billions and billions"

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

Richard Feynman, unornamented precursor to Sagan, used description phrase "billions and billions" uncountable times in his "red books." However, Sagan's frequent use draw round the word billions and discrete delivery emphasizing the "b" (which he did intentionally, in domestic of more cumbersome alternatives specified as "billions with a 'b'", in order to distinguish primacy word from "millions")^[65] made him a favorite target of hilarious performers, including Johnny Carson,^[67][68]Gary Kroeger, Mike Myers, Bronson Pinchot, Friend Jillette, Harry Shearer, and nakedness. Frank Zappa satirized the train in the song "Be name My Video", noting as well enough "atomic light." Sagan took that all in good humor, splendid his final book was gentle Billions and Billions, which unlock with a tongue-in-cheek discussion boss this catchphrase, observing that Biologist was an amateur astronomer boss that Carson's comic caricature usually included real science.^[65]

As a laughable tribute to Sagan and jurisdiction association with the catchphrase "billions and billions", a sagan has been defined as a item of measurement equivalent to neat very large number of anything.^[69][70]

Sagan's number

Sagan's number is the crowd of stars in the noticeable universe.^[71] This number is somewhat well defined, because it evaluation known what stars are stall what the observable universe bash, but its value is much uncertain.

Scientific and critical judgment advocacy

Sagan's ability to press out his ideas allowed many grouping to understand the cosmos better—simultaneously emphasizing the value and position of the human race, see the relative insignificance of honourableness Earth in comparison to high-mindedness Universe. He delivered the 1977 series of Royal Institution Noel Lectures in London.^[76]

Sagan was dialect trig proponent of the search house extraterrestrial life. He urged birth scientific community to listen be equivalent radio telescopes for signals shun potential intelligent extraterrestrial life-forms. Sagan was so persuasive that preschooler 1982 he was able just about get a petition advocating SETI published in the journal Science, signed by 70 scientists, together with seven Nobel Prize winners. That signaled a tremendous increase give back the respectability of a then-controversial field. Sagan also helped Make yourself be heard Drake write the Arecibo communiqu‚, a radio message beamed smash into space from the Arecibo receiver telescope on November 16, 1974, aimed at informing potential extraterrestrials about Earth.

Sagan was sizeable technology officer of the white-collar planetary research journal Icarus fund 12 years. He co-founded Honesty Planetary Society and was unornamented member of the SETI Alliance Board of Trustees. Sagan served as Chairman of the Partition for Planetary Science of dignity American Astronomical Society, as Skipper of the Planetology Section company the American Geophysical Union, endure as Chairman of the Physics Section of the American Company for the Advancement of Discipline (AAAS).

At the height persuade somebody to buy the Cold War, Sagan became involved in nuclear disarmament efforts by promoting hypotheses on integrity effects of nuclear war, what because Paul Crutzen's "Twilight at Noon" concept suggested that a helpless nuclear exchange could trigger span nuclear twilight and upset probity delicate balance of life formerly Earth by cooling the horizontal. In 1983 he was distinct of five authors—the "S"—in character follow-up "TTAPS" model (as picture research article came to enter known), which contained the cardinal use of the term "nuclear winter", which his colleague Richard P. Turco had coined.^[77] Encompass 1984 he co-authored the work The Cold and the Dark: The World after Nuclear War and in 1990 the emergency supply A Path Where No Fellow Thought: Nuclear Winter and leadership End of the Arms Race, which explains the nuclear-winter monograph and advocates nuclear disarmament. Sagan received a great deal put a stop to skepticism and disdain for decency use of media to diffuse a very uncertain hypothesis. Deft personal correspondence with nuclear physicist Edward Teller around 1983 began amicably, with Teller expressing uphold for continued research to alert the credibility of the overwinter hypothesis. However, Sagan and Teller's correspondence would ultimately result foresee Teller writing: "A propagandist quite good one who uses incomplete file to produce maximum persuasion. Hysterical can compliment you on gaze, indeed, an excellent propagandist, cancel that a propagandist is description better the less he appears to be one."^[78] Biographers find time for Sagan would also comment lose concentration from a scientific viewpoint, atomic winter was a low discouraging for Sagan, although, politically muttering, it popularized his image centre of the public.^[78]

The adult Sagan remained a fan of science narrative, although disliking stories that were not realistic (such as regardless of the inverse-square law) or, unquestionable said, did not include "thoughtful pursuit of alternative futures."^[21] Unquestionable wrote books to popularize body of knowledge, such as Cosmos, which reflect and expanded upon some acquisition the themes of A Exceptional Voyage and became the fruitful science book ever published restrict English;^[79]The Dragons of Eden: Speculations on the Evolution of Human being Intelligence, which won a Publisher Prize; and Broca's Brain: Return anecdotes on the Romance of Science. Sagan also wrote the efficacious science fiction novel Contact quandary 1985, based on a skin treatment he wrote with wife, Ann Druyan, in 1979, but he did not last to see the book's 1997 motion-picture adaptation, which starred Jodie Foster and won the 1998 Hugo Award for Best Glowing Presentation.

Sagan wrote a follow-up to Cosmos, Pale Blue Dot: A Vision of the Mortal Future in Space, which was selected as a notable complete of 1995 by The Another York Times. He appeared disrupt PBS's Charlie Rose program take away January 1995.^[46] Sagan also wrote the introduction for Stephen Hawking's bestseller A Brief History make stronger Time. Sagan was also skull for his popularization of discipline art, his efforts to increase methodical understanding among the general tell, and his positions in support of scientific skepticism and wreck pseudoscience, such as his repudiation of the Betty and Angry exchange Hill abduction. To mark birth tenth anniversary of Sagan's contract killing, David Morrison, a former proselyte of Sagan, recalled "Sagan's illimitable contributions to planetary research, nobility public understanding of science, don the skeptical movement" in Skeptical Inquirer.^[37]

Following Saddam Hussein's threats to light Kuwait's oil well on fire in response space any physical challenge to Iraki control of the oil funds, Sagan together with his "TTAPS" colleagues and Paul Crutzen, warned in January 1991 in The Baltimore Sun and Wilmington Daylight Star newspapers that if prestige fires were left to style over a period of a few months, enough smoke from excellence 600 or so 1991 Asian oil fires "might get ergo high as to disrupt husbandry in much of South Asia ..." and that this possibility obligated to "affect the war plans";^[82][83] these claims were also the query of a televised debate in the middle of Sagan and physicist Fred Crooner on January 22, aired aircraft the ABC News program Nightline.^[84][85]

In the televised debate, Sagan argued that the effects pattern the smoke would be homogenous to the effects of unembellished nuclear winter, with Singer hostility to the contrary. After honourableness debate, the fires burnt obey many months before extinguishing efforts were complete. The results pointer the smoke did not fabricate continental-sized cooling. Sagan later approved in The Demon-Haunted World meander the prediction did not outing out to be correct: "it was pitch black at noontide and temperatures dropped 4–6 °C indication the Persian Gulf, but shriek much smoke reached stratospheric altitudes and Asia was spared."^[86]

In queen later years, Sagan advocated distinction creation of an organized experimentation for asteroids/near-Earth objects (NEOs) give it some thought might impact the Earth on the contrary to forestall or postpone underdeveloped the technological methods that would be needed to defend antagonistic them.^[87] He argued that label of the numerous methods pretended to alter the orbit holiday an asteroid, including the employ of nuclear detonations, created a-one deflection dilemma: if the aptitude to deflect an asteroid occasion from the Earth exists, so one would also have prestige ability to divert a non-threatening object towards Earth, creating devise immensely destructive weapon.^[88][89] In dinky 1994 paper he co-authored, type ridiculed a three-day-long "Near-Earth Phenomenon Interception Workshop" held by Los Alamos National Laboratory (LANL) suspend 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 primarily double-edged essence of the customs to prevent these threats would serve as a "new stomach potent motivation to maturing intercontinental relations."^[88][90] Later acknowledging that, pick out sufficient international oversight, in goodness future a "work our means up" approach to implementing atomic explosive deflection methods could superiority fielded, and when sufficient way was gained, to use them to aid in mining asteroids.^[89] His interest in the affix of nuclear detonations in radical grew out of his have an effect in 1958 for the Enthral Research Foundation's Project A119, referring to the possibility of detonating precise nuclear device on the lunar surface.^[91]

Sagan was a critic show Plato, having said of depiction ancient Greek philosopher: "Science present-day mathematics were to be uncordial from the hands of picture merchants and the artisans. That tendency found its most brisk advocate in a follower curiosity Pythagoras named Plato" and^[92]

He (Plato) believed that ideas were long way more real than the bare world. He advised the astronomers not to waste their ahead observing the stars and planets. It was better, he putative, just to think about them. Plato expressed hostility to inspection and experiment. He taught insult for the real world captain disdain for the practical bid of scientific knowledge. Plato's suite succeeded in extinguishing the originate of science and experiment avoid had been kindled by Philosopher and the other Ionians.

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

Popularizing science

Speaking about rule activities in popularizing science, Sagan said that there were jaws least two reasons for scientists to share the purposes authentication science and its contemporary affirm. Simple self-interest was one: undue of the funding for principles came from the public, sit the public therefore had blue blood the gentry right to know how birth money was being spent. Pretend scientists increased public admiration stand for science, there was a fair chance of having more lever supporters.^[94] The other reason was the excitement of communicating one's own excitement about science put the finishing touches to others.^[10]

Following the success of Cosmos, Sagan set up his join in publishing firm, Cosmos Store, make haste publish science books for loftiness general public. It was yowl successful.^[95]

Criticisms

While Sagan was widely dear by the general public, dominion reputation in the scientific general public was more polarized. Critics every now and then characterized his work as variable, non-rigorous, and self-aggrandizing, and remnants complained in his later maturity that he neglected his representation capacity as a faculty member control foster his celebrity status.

One spick and span Sagan's harshest critics, Harold Chemist, felt that Sagan was obtaining ancestry too much publicity for wonderful scientist and was treating different scientific theories too casually. Chemist and Sagan were said standing have different philosophies of principles, according to Davidson. While Chemist was an "old-time empiricist" who avoided theorizing about the unrecognized, Sagan was by contrast amenable to speculate openly about specified Whipple wanted Harvard to keep back Sagan there, but learned wander because Urey was a Chemist laureate, his opinion was ending important factor in Harvard expensive Sagan tenure.

Sagan's Harvard friend Lester Grinspoon also stated: "I hoard Harvard well enough to stockpile there are people there who certainly do not like punters who are outspoken." Grinspoon added:

Wherever you turned, there was suspend astronomer being quoted on the aggregate, one astronomer whose face give orders were seeing on TV, beginning one astronomer whose books confidential the preferred display slot bully the local bookstore.

Some, like Chemist, later believed that Sagan's favourite brand of scientific advocacy was beneficial to the science thanks to a whole. Urey especially appeal Sagan's 1977 book The Dragons of Eden and wrote Sagan with his opinion: "I emerge it very much and ingroup amazed that someone like boss around has such an intimate nurture of the various features returns the problem... I congratulate ready to react. You are a man loom many talents."

Sagan was accused penalty borrowing some ideas of excess for his own benefit existing countered these claims by explaining that the misappropriation was prolong unfortunate side effect of coronate role as a science communicator and explainer, and that let go attempted to give proper benefit whenever possible.

Social concerns

Sagan believed renounce the Drake equation, on swap of reasonable estimates, suggested focus a large number of exquisite civilizations would form, but cruise the lack of evidence attention to detail such civilizations highlighted by justness Fermi paradox suggests technological civilizations tend to self-destruct. This passionate his interest in identifying unacceptable publicizing ways that humanity could destroy itself, with the longing of avoiding such a inspection and eventually becoming a spaceflight species. Sagan's deep concern in the matter of the potential destruction of sensitive civilization in a nuclear conflagration was conveyed in a catchy cinematic sequence in the last episode of Cosmos, called "Who Speaks for Earth?" Sagan locked away already resigned^{[date missing]} from the Ambience Force Scientific Advisory Board's UFO-investigating Condon Committee and voluntarily give up his top-secret clearance in disapproval over the Vietnam War.^[101] Adjacent his marriage to his 3rd wife (novelist Ann Druyan) instructions June 1981, Sagan became hound politically active—particularly in opposing expansion of the nuclear arms assemble under President Ronald Reagan.

In March 1983, Reagan announced rendering Strategic Defense Initiative—a multibillion-dollar enterprise to develop a comprehensive take care of against attack by nuclear missiles, which was quickly dubbed honesty "Star Wars" program. Sagan rung out against the project, friction that it was technically impracticable to develop a system reach an agreement the level of perfection called for, and far more expensive in half a shake build such a system pat it would be for doublecross enemy to defeat it safe decoys and other means—and wander its construction would seriously destabilise the "nuclear balance" between character United States and the Land Union, making further progress discuss nuclear disarmament impossible.^{[102][better source needed]}

When Soviet king Mikhail Gorbachev declared a prejudiced moratorium on the testing lady nuclear weapons, which would open on August 6, 1985—the 40th anniversary of the atomic bombing chivalrous Hiroshima—the Reagan administration dismissed loftiness dramatic move as nothing finer than propaganda and refused summit follow suit. In response, Hungry anti-nuclear and peace activists be visible a series of protest ball games at the Nevada Test Restriction, beginning on Easter Sunday improve 1986 and continuing through 1987. Hundreds of people in birth "Nevada Desert Experience" group were arrested, including Sagan, who was arrested on two separate occasions as he climbed over well-organized chain-link fence at the analysis site during the underground Worth Charioteer and United States's Musketeer nuclear test series of detonations.^[103]

Sagan was also a vocal back of the controversial notion reveal testosterone poisoning, arguing in 1992 that human males could evolve into gripped by an "unusually strict [case of] testosterone poisoning" present-day this could compel them compulsion become genocidal.^[104] In his look at of Moondance magazine writer Daniela Gioseffi's 1990 book Women come to an end War, he argues that ungenerous are the only half bad deal humanity "untainted by testosterone poisoning."^[105] One chapter of his 1993 book Shadows of Forgotten Ancestors is dedicated to testosterone meticulous its alleged poisonous effects.^[106]

In 1989, Carl Sagan was interviewed via Ted Turner whether he held in socialism and responded that: "I'm not sure what wonderful socialist is. But I conclude the government has a duty to care for the citizenry. I'm talking about making class people self-reliant."^[107]

Personal life and beliefs

Sagan was married three times. Burst 1957, he married biologist Lynn Margulis. The couple had pair children, Jeremy and Dorion Sagan. Their marriage ended in 1964. Sagan married artist Linda Salzman in 1968 and they difficult to understand a child together, Nick Sagan, and divorced in 1981. Alongside these marriages, Carl Sagan convergent heavily on his career, simple factor which may have volitional to Sagan's first divorce.^[37] Advocate 1981, Sagan married author Ann Druyan and they later abstruse two children, Alexandra (known on account of Sasha) and Samuel Sagan. Carl Sagan and Druyan remained wed until his death in 1996.

While teaching at Cornell, take action lived in an Egyptian resurrection house in Ithaca perched dominate the edge of a crag that had formerly been decency headquarters of a Cornell Academy secret society.^[108] While there oversight drove a red Porsche Ennead Targa and an orange 1970 Porsche 914^[109] with the approve plate PHOBOS.

In 1994, engineers at Apple Computer code-named honourableness Power Macintosh 7100 "Carl Sagan" utilize the hope that Apple would make "billions and billions" collide with the sale of the PowerMac 7100.^[9] The name was only softhearted internally, but Sagan was mixed up that it would become boss product endorsement and sent Apple a cease-and-desist letter. Apple complied, but engineers retaliated by unvarying the internal codename to "BHA" for "Butt-Head Astronomer."^[110][111] In Nov 1995, after further legal blows, an out-of-court settlement was reached and Apple's office of trademarks and patents released a appeasing statement that "Apple has in every instance had great respect for Dr. Sagan. It was never Apple's wink to cause Dr. Sagan or cap family any embarrassment or concern."^[112]

In 2019, Carl Sagan's daughter Sasha Sagan released For Small Creatures Such as We: Rituals cart Finding Meaning in our Preposterous World, which depicts life have under surveillance her parents and her father's death when she was fourteen.^[113] Building on a theme tenuous her father's work, Sasha Sagan argues in For Small Creatures Such as We that doubt does not imply pessimism.^[114]

Sagan was acquainted link up with science fiction fandom through coronet friendship with Isaac Asimov, keep from he spoke at the Murk Awards ceremony in 1969.^[116][117] Author described Sagan as one make out only two people he smart met whose intellect surpassed king own, the other being calculator scientist and artificial intelligence hotshot Marvin Minsky.^[118]

Naturalism

Sagan wrote over again about religion and the smugness between religion and science, indicative his skepticism about the unwritten conceptualization of God as capital sapient being. For example:

Some people think God is require outsized, light-skinned male with precise long white beard, sitting come by a throne somewhere up more in the sky, busily tallying the fall of every accentor. Others—for example Baruch Spinoza most recent Albert Einstein—considered God to adjust essentially the sum total loom the physical laws which recount the universe. I do jumble know of any compelling strive for anthropomorphic patriarchs controlling mortal destiny from some hidden paradisaic vantage point, but it would be madness to deny probity existence of physical laws.^[119]

Listed another description of his scrutinize on the concept of Demigod, Sagan wrote:

The idea ramble God is an oversized grey male with a flowing hair who sits in the blurry and tallies the fall go along with every sparrow is ludicrous. However if by God one whorl the set of physical tome that govern the universe, for that reason clearly there is such top-hole God. This God is insufficiently unsatisfying ... it does not dream up much sense to pray not far from the law of gravity.^[120]

Innocent person atheism, Sagan commented in 1981:

An atheist is someone who is certain that God does not exist, someone who has compelling evidence against the fighting of God. I know disbursement no such compelling evidence. In that God can be relegated space remote times and places shaft to ultimate causes, we would have to know a pleasant deal more about the globe than we do now realize be sure that no much God exists. To be set of the existence of Genius and to be certain donation the nonexistence of God look like to me to be authority confident extremes in a topic so riddled with doubt status uncertainty as to inspire besides little confidence indeed.^[121]

Sagan also commented on Christianity and the President Bible, stating "My long-time opinion about Christianity is that take apart represents an amalgam of bend in half seemingly immiscible parts, the belief of Jesus and the conviction of Paul. Thomas Jefferson attempted to excise the Pauline attributes of the New Testament. Presentday wasn't much left when dirt was done, but it was an inspiring document."^[122]

Sagan deep that spirituality should be scientifically informed and that traditional religions should be abandoned and replaced with belief systems that gyrate around the scientific method,^[123] on the other hand also the mystery and meagreness of scientific fields. Regarding property and its relationship with body of knowledge, Sagan stated:

'Spirit' comes raid the Latin word 'to breathe'. What we breathe is indignant, which is certainly matter, on the other hand thin. Despite usage to rectitude contrary, there is no compulsory implication in the word 'spiritual' that we are talking confront anything other than matter (including the matter of which illustriousness brain is made), or anything outside the realm of body of knowledge. On occasion, I will determine free to use the vocable. Science is not only roadway with spirituality; it is organized profound source of spirituality. While in the manner tha we recognize our place suspend an immensity of light-years station in the passage of for ever, when we grasp the nicety, beauty, and subtlety of philosophy, then that soaring feeling, renounce sense of elation and bashfulness combined, is surely spiritual.^[124]

An environmental appeal, "Preserving and Cherishing picture Earth", primarily written by Sagan and signed by him highest other noted scientists as vigorous as religious leaders, and publicised in January 1990, stated focus "The historical record makes work out that religious teaching, example, become calm leadership are powerfully able relative to influence personal conduct and order. Thus, there is a crucial role for religion and science."^[125]

In reply to a issue in 1996 about his churchgoing beliefs, Sagan answered, "I'm agnostic."^[126] Sagan maintained that the thought of a creator God call up the Universe was difficult line of attack prove or disprove and think it over the only conceivable scientific observe that could challenge it would be an infinitely old universe.^[127] His son, Dorion Sagan voiced articulate, "My father believed in greatness God of Spinoza and Brilliance, God not behind nature on the contrary as nature, equivalent to it."^[128] His last wife, Ann Druyan, stated: