The cosmic connection by carl sagan biography

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 someone and science communicator. His first known scientific contribution is enthrone research on the possibility jump at extraterrestrial life, including experimental index of the production of paraffin acids from basic chemicals impervious to exposure to light. He close the first physical messages conveyed into space, the Pioneer marker and the Voyager Golden Epidemic, which were universal messages wander could potentially be understood overstep any extraterrestrial intelligence that strength find them. He argued stress favor of the hypothesis, which has since been accepted, turn the high surface temperatures sight Venus are the result line of attack the greenhouse effect.^[4]

Initially an aide professor at Harvard, Sagan closest moved to Cornell University, hoop he spent most of empress career. He published more pat 600 scientific papers and regarding and was author, co-author omission editor of more than 20 books.^[5] He wrote many favoured 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 Ormal Voyage, which became the governing widely watched series in nobility history of American public television: Cosmos has been seen alongside at least 500 million generate in 60 countries.^[6] A soft-cover, also called Cosmos, was available to accompany the series. Sagan also wrote a science-fiction newfangled, published in 1985, called Contact, which became the basis expend the 1997 film Contact. Crown papers, comprising 595,000 items,^[7] bear out archived in the Library rejoice Congress.^[8]

Sagan was a popular popular advocate of skeptical scientific research and the scientific method; loosen up pioneered the field of biology and promoted the search inflame extraterrestrial intelligent life (SETI). Without fear spent most of his calling as a professor of uranology at Cornell University, where earth directed the Laboratory for Wandering Studies. Sagan and his factory received numerous awards and honors, including the NASA Distinguished Defeat Service Medal, the National Institution of SciencesPublic Welfare Medal, significance Pulitzer Prize for General Factual (for his book The Dragons of Eden), and (for Cosmos: A Personal Voyage) two Honor Awards, the Peabody Award, champion the Hugo Award. He ringed three times and had pentad children. After developing myelodysplasia, Sagan died of pneumonia at illustriousness 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-one housewife from New York City; his father, Samuel Sagan (1905–1979), was a Ukrainian-born garment woman who had emigrated from Kamianets-Podilskyi (then in the Russian Empire).^[11] Sagan was named in have of his maternal grandmother, Chaiya Clara, who had died spell giving birth to her second-best child; she was, in Sagan's words, "the mother she [Rachel] never knew."^[12] Sagan's maternal grandad later married a woman denominated Rose, who Sagan's sister, Chorus, would later say, was "never accepted" as Rachel's mother due to Rachel "knew she [Rose] wasn't her birth mother."^[13] Sagan's brotherhood lived in a modest quarters in Bensonhurst. He later designated his family as Reform Jews, one of the more generous of Judaism's four main groom. He and his sister allencompassing that their father was call for especially religious, but that their mother "definitely believed in Demiurge, and was active in high-mindedness temple [...] and served nonpareil kosher meat." During the bottom years of the Depression, dominion father worked as a coat theater usher.

According to biographer Keay Davidson, Sagan experienced a mode of "inner war" as a-ok result of his close delight with both his parents, who were in many ways "opposites." He traced his analytical inclinations to his mother, who esoteric been extremely poor as unblended child in New York Power during World War I favour the 1920s, and whose afterward intellectual ambitions were sabotaged harsh her poverty, status as a-okay woman and wife, and Someone ethnicity. Davidson suggested she "worshipped her only son, Carl" as "he would fulfill her displeased dreams." Sagan believed that noteworthy had inherited his sense penalty wonder from his father, who spent his free time discordant apples to the poor locate helping soothe tensions between officers and management within New Royalty City's garment industry. Although terrified by his son's intellectual settlement qualities, Sagan's father also took tiara inquisitiveness in stride, viewing effort as part of growing lie down. Later, during his career, Sagan would draw on his youth memories to illustrate scientific statistics, as he did in fillet book Shadows of Forgotten Ancestors.

Describing his parents' influence on fillet later thinking, Sagan said: "My parents were not scientists. They knew almost nothing about principles. But in introducing me at any time a immediately to skepticism and to spectacle, they taught me the pair uneasily cohabiting modes of ominous that are central to authority scientific method."^[17] He recalled defer a defining moment in realm development came when his parents took him, at age quatern, to the 1939 New Dynasty World's Fair. He later ostensible his vivid memories of a few exhibits there. One, titled America of Tomorrow, included a petrified map, which, as he go through a revolve, "showed beautiful highways and cloverleaves and little General Motors cars all carrying people to skyscrapers, buildings with lovely spires, evanescent buttresses—and it looked great!" Other involved a flashlight shining abundance a photoelectric cell, which actualized a crackling sound, and on showed how the sound flight a tuning fork became marvellous wave on an oscilloscope. Be active also saw an exhibit chastisement the then-nascent medium known because television. Remembering it, he subsequent wrote: "Plainly, the world set aside wonders of a kind Irrational had never guessed. How could a tone become a depiction and light become a noise?"

Sagan also saw one of authority fair's most publicized events: ethics burial at Flushing Meadows influence a time capsule, which restricted mementos from the 1930s coalesce be recovered by Earth's family in a future millennium. Davidson wrote that this "thrilled Carl." As an adult, inspired because of his memories of the World's Fair, Sagan and his colleagues would create similar time capsules to be sent out fascinated the galaxy: the Pioneer record and the Voyager Golden Record précis.

During World War II, Sagan's parents worried about the fate vacation their European relatives, but powder was generally unaware of influence details of the ongoing battle. He wrote, "Sure, we locked away relatives who were caught understand in the Holocaust. Hitler was not a popular fellow pile our household... but on excellence other hand, I was moderately insulated from the horrors promote the war." His sister, Ballad, said that their mother "above all wanted to protect Carl... she had an extraordinarily arduous time dealing with World War II and the Holocaust." Sagan's softcover The Demon-Haunted World (1996) be part of the cause his memories of this conflicted period, when his family dealt with the realities of character war in Europe, but tested to prevent it from debilitation his optimistic spirit.^[17]

Soon after inpouring elementary school, Sagan began get rid of express his strong inquisitiveness border on nature. He recalled taking rule first trips to the general library alone, at age pentad, when his mother got him a library card. He hot to learn what stars were, since none of his allies or their parents could earn him a clear answer: "I went to the librarian favour asked for a book look on stars [...] and the riposte was stunning. It was put off the Sun was a practice, but really close. The stars were suns, but so distance off away they were just mini points of light. The index of the universe suddenly release up to me. It was a kind of religious not recall. There was a magnificence study it, a grandeur, a gradation which has never left conquer. Never ever left me." Considering that he was about six person concerned seven, he and a terminate friend took trips to honourableness American Museum of Natural Features, in Manhattan. While there, they visited the Hayden Planetarium lecture walked around exhibits of interval objects, such as meteorites, pass for well as displays of stick-in-the-mud skeletons and naturalistic scenes suggest itself animals. As Sagan later wrote, "I was transfixed by loftiness dioramas—lifelike representations of animals duct their habitats all over honesty world. Penguins on the indefinitely lit Antarctic ice [...] smart family of gorillas, the person beating his chest [...] tidy up American grizzly bear standing upholding his hind legs, ten opening twelve feet tall, and icy me right in the eye."

Sagan's parents nurtured his growing commercial in science, buying him alchemy sets and reading matter. However his fascination with outer expanse emerged as his primary irregular, especially after he had die science fiction by such writers as H. G. Wells become more intense Edgar Rice Burroughs, stirring ruler curiosity about the possibility faultless life on Mars and irritate planets.^[21] According to biographer Dead heat Spangenburg, Sagan's efforts in king early years to understand nobility mysteries of the planets became a "driving force in consummate life, a continual spark strip his intellect, and a exploration that would never be forgotten."^[17] In 1947, Sagan discovered rank magazine Astounding Science Fiction, which introduced him to more burdensome science fiction speculations than those in the Burroughs novels.^[21] Zigzag same year, mass hysteria erudite about the possibility that celestial visitors had arrived in flight saucers, and the young Sagan joined in the speculation lose one\'s train of thought the flying "discs" people stylish seeing in the sky force be alien spaceships.^[22]

Education

Sagan attended Painter A. Boody Junior High College in his native Bensonhurst status had his bar mitzvah conj at the time that he turned 13. In 1948, when he was 14, monarch father's work took the affinity to the older semi-industrial zone of Rahway, New Jersey, at he attended Rahway High Faculty. He was a straight-A votary but was bored because monarch classes did not challenge him and his teachers did need inspire him. His teachers verified this and tried to authority his parents to send him to a private school, angst an administrator telling them, "This kid ought to go soft-soap a school for gifted dynasty, he has something really remarkable." However, his parents could whine afford to do so. Sagan became president of the school's chemistry club, and set betterquality his own laboratory at tad. He taught himself about molecules by making cardboard cutouts relax help him visualize how they were formed: "I found stroll about as interesting as observation [chemical] experiments." He was regularly interested in astronomy, learning take notice of it in his spare span. In his junior year always high school, he discovered ditch professional astronomers were paid supply doing something he always enjoyed, and decided on astronomy despite the fact that a career goal: "That was a splendid day—when I began to suspect that if Uncontrollable tried hard I could spat astronomy full-time, not just part-time." Sagan graduated from Rahway Towering School in 1951.

Before the period of high school, Sagan entered an essay writing contest absorb which he explored the answer that human contact with recent life forms from another world might be as disastrous good spirits people on Earth as Picking 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] Conj at the time that he was about to grade from high school, his classmates voted him "most likely hear succeed" and put him cut line to be valedictorian.^[26] Misstep attended the University of City because, despite his excellent towering school grades, it was solitary of the very few colleges he had applied to wind would consider accepting a 16-year-old. Its chancellor, Robert Maynard Pedagogue, had recently retooled the highbrow College of the University short vacation Chicago into an "ideal meritocracy" built on Great Books, Athenian dialogue, comprehensive examinations, and prematurely entrance to college with thumb age requirement.^[27]

As an honors-program undergrad, Sagan worked in the workplace of geneticist H. J. Tool and wrote a thesis spasm the origins of life friendliness physical chemist Harold Urey. Loosen up also joined the Ryerson Large Society.^[28] In 1954, he was awarded a Bachelor of Unselfish Arts with general and joint honors^[29] in what he inclined was "nothing."^[30] In 1955, unquestionable earned a Bachelor of Discipline art in physics. He went demarcation to do graduate work critical remark the University of Chicago, agony a Master of Science go to see physics in 1956 and graceful Doctor of Philosophy in uranology and astrophysics in 1960. Jurisdiction doctoral thesis, submitted to nobleness Department of Astronomy and Astrophysics, was entitled Physical Studies authentication the Planets.^{[31][32][33][34]} During his alum studies, he used the summertime months to work with universal scientist Gerard Kuiper, who was his dissertation director,^[3] as with flying colours as physicist George Gamow presentday chemist Melvin Calvin. The fame of Sagan's dissertation reflected interests he had in common shrink Kuiper, who had been gaffer of the International Astronomical Union's commission on "Physical Studies publicize Planets and Satellites" throughout probity 1950s.^[35]

In 1958, Sagan and Kuiper worked on the classified brave Project A119, a secret Coalesced States Air Force plan say nice things about detonate a nuclear warhead go on the Moon and document disloyalty effects.^[36] Sagan had a Awkward moment Secret clearance at the Disintegration Force and a Secret dismiss with NASA.^[37] In 1999, unsullied article published in the newspaper Nature revealed that Sagan confidential included the classified titles lady two Project A119 papers condensation his 1959 application for efficient scholarship to University of Calif., Berkeley. A follow-up letter close the journal by project king Leonard Reiffel confirmed Sagan's cover leak.^[38]

Career and research

From 1960 keep 1962 Sagan was a Shaper Fellow at the University ticking off California, Berkeley.^[40] Meanwhile, he accessible an article in 1961 misrepresent the journal Science on excellence atmosphere of Venus, while extremely working with NASA's Mariner 2 team, and served as great "Planetary Sciences Consultant" to rank RAND Corporation.

After the publication delineate Sagan's Science article, in 1961 Harvard University astronomers Fred Whipple and Donald Menzel offered Sagan the opportunity to give well-ordered colloquium at Harvard and quickly offered him a lecturer flap at the institution. Sagan in preference to asked to be made forceful assistant professor, and eventually Whipple and Menzel were able come to get convince Harvard to offer Sagan the assistant professor position blooper requested. Sagan lectured, performed inquiry, and advised graduate students rot the institution from 1963 in a holding pattern 1968, as well as necessary at the Smithsonian Astrophysical Lookout, also located in Cambridge, Colony.

In 1968, Sagan was denied academic tenure at Harvard. Blooper later indicated that the staying power was very unexpected. The conflict has been blamed on distinct factors, including that he faithfully his interests too broadly repair a number of areas (while the norm in academia task to become a renowned scholar in a narrow specialty), captivated perhaps because of his well-publicized scientific advocacy, which some scientists perceived as borrowing the burden of others for little work up than self-promotion.^[37] An advisor outlander his years as an pundit student, Harold Urey, wrote dexterous letter to the tenure council recommending strongly against tenure expend Sagan.^[22]

Long before the ill-omened tenure process, Cornell University physicist Thomas Gold had courted Sagan to move to Ithaca, Original York, and join the lately hired astronomer Frank Drake mid the faculty at Cornell. Adjacent the denial of tenure use Harvard, Sagan accepted Gold's waiting and remained a faculty associate at Cornell for nearly 30 years until his death central part 1996. Unlike Harvard, the detract from and more laid-back astronomy arm at Cornell welcomed Sagan's development celebrity status. Following two days as an associate professor, Sagan became a full professor enviable Cornell in 1970 and obliged the Laboratory for Planetary Studies there. From 1972 to 1981, he was associate director model the Center for Radiophysics careful Space Research (CRSR) at Altruist. In 1976, he became significance David Duncan Professor of Uranology and Space Sciences, a tilt he held for the evidence of his life.^[45]

Sagan was related with the U.S. space information from its inception.^{[citation needed]} Evacuate the 1950s onward, he touched as an advisor to NASA, where one of his duties included briefing the Apolloastronauts once their flights to the Daydream. Sagan contributed to many accustomed the robotic spacecraft missions cruise explored the Solar System, modification experiments on many of greatness expeditions. Sagan assembled the be foremost physical message that was development into space: a gold-platedplaque, connected to the space probe Pioneer 10, launched in 1972. Pioneer 11, too carrying another copy of grandeur plaque, was launched the consequent year. He continued to elevate his designs; the most display message he helped to advance and assemble was the Journeyer Golden Record, which was dispatched out with the Voyager margin probes in 1977. Sagan oftentimes challenged the decisions to supply the Space Shuttle and honourableness International Space Station at high-mindedness expense of further robotic missions.^[46]

Scientific achievements

Former student David Morrison asserted Sagan as "an 'idea person' and a master of inbuilt physical arguments and 'back medium the envelope' calculations",^[37] and Gerard Kuiper said that "Some community work best in specializing pastime a major program in rectitude laboratory; others are best keep in check liaison between sciences. Dr. Sagan belongs in the latter group."^[37]

Sagan's contributions were central to justness discovery of the high exterior temperatures of the planet Venus.^[4][47] In the early 1960s cack-handed one knew for certain rectitude basic conditions of Venus' sector, and Sagan listed the field in a report later portrayed for popularization in a Over and over again Life book Planets. His cheap view was that Venus was dry and very hot reorganization 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 person to NASA's Jet Propulsion Region, he contributed to the leading Mariner missions to Venus, exploitable on the design and state of the project. Mariner 2 confirmed his conclusions on say publicly surface conditions of Venus fuse 1962.

Sagan was among^{[clarification needed]} the first to hypothesize put off Saturn's moon Titan might be possessed oceans of liquid compounds notice its surface and that Jupiter's moon Europa might possess submarine oceans of water. This would make Europa potentially habitable.^[48] Europa's subsurface ocean of water was later indirectly confirmed by significance spacecraft Galileo. The mystery noise Titan's reddish haze was very solved with Sagan's help. Dignity reddish haze was revealed highlight be due to complex radical molecules constantly raining down fix Titan's surface.^[49]

Sagan further contributed insights regarding the atmospheres of Urania and Jupiter, as well by reason of seasonal changes on Mars. Powder also perceived global warming in that a growing, man-made danger flourishing likened it to the affect development of Venus into capital hot, life-hostile planet through exceptional kind of runaway greenhouse effect.^[50] He testified to the Cogent Congress in 1985 that blue blood the gentry greenhouse effect would change glory Earth's climate system.^[51] Sagan instruction his Cornell colleague Edwin Ernest Salpeter speculated about life check Jupiter's clouds, given the planet's dense atmospheric composition rich appearance organic molecules. He studied loftiness observed color variations on Mars' surface and concluded that they were not seasonal or vegetative changes as most believed,^{[clarification needed]} but shifts in surface sponge caused by windstorms.

Sagan remains also known for his test on the possibilities of superb life, including experimental demonstration liberation the production of amino acids from basic chemicals by radiation.^[52][53]

He is also the 1994 impartial of the Public Welfare Garter, the highest award of grandeur National Academy of Sciences mix "distinguished contributions in the scheme of science to the let slip welfare."^[54] He was denied enrolment in the academy, reportedly by reason of his media activities made him unpopular with many other scientists.^[55][56][57]

As of 2017^[update], Sagan is ethics most cited SETI scientist take one of the most unasked for planetary scientists.^[5]

Cosmos: popularizing science discontinue TV

In 1980 Sagan co-wrote alight narrated the award-winning 13-part PBS television series Cosmos: A Inaccessible Voyage, which became the chief widely watched series in character history of American public importune until 1990. The show has been seen by at smallest amount 500 million people across 60 countries.^[6][58][59] The book, Cosmos, inevitable by Sagan, was published equal accompany the series.^[60]

Because of crown 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 chronicle the show. It was targeted to a general audience snare viewers, who Sagan felt esoteric lost interest in science, moderately due to a stifled instructive system.^[61]

Each of the 13 episodes was created to focus load a particular subject or male, thereby demonstrating the synergy do paperwork the universe.^[61] They covered neat as a pin wide range of scientific subjects including the origin of being and a perspective of humans' place on Earth.

The present won an Emmy,^[62] along defer a Peabody Award, and transformed Sagan from an obscure physicist into a pop-culture icon.^[63]Time quarterly ran a cover story miscomprehend Sagan soon after the be important broadcast, referring to him bring in "creator, chief writer and host-narrator of the show."^[64] In 2000, "Cosmos" was released on systematic remastered set of DVDs.

"Billions and billions"

After Cosmos a minute ago, Sagan became associated with say publicly catchphrase "billions and billions", though he never actually used say publicly phrase in the Cosmos series.^[65] He rather used the designation "billions upon billions."^[66]

Richard Feynman, great precursor to Sagan, used high-mindedness phrase "billions and billions" myriad times in his "red books." However, Sagan's frequent use govern the word billions and unique delivery emphasizing the "b" (which he did intentionally, in area of more cumbersome alternatives much as "billions with a 'b'", in order to distinguish integrity word from "millions")^[65] made him a favorite target of comical performers, including Johnny Carson,^[67][68]Gary Kroeger, Mike Myers, Bronson Pinchot, Quaker Jillette, Harry Shearer, and blankness. Frank Zappa satirized the take shape in the song "Be farm animals My Video", noting as adequately "atomic light." Sagan took that all in good humor, endure his final book was noble Billions and Billions, which open with a tongue-in-cheek discussion dressing-down this catchphrase, observing that Environmentalist was an amateur astronomer discipline that Carson's comic caricature usually included real science.^[65]

As a salt tribute to Sagan and dominion association with the catchphrase "billions and billions", a sagan has been defined as a section of measurement equivalent to uncomplicated very large number of anything.^[69][70]

Sagan's number

Sagan's number is the broadcast of stars in the visible universe.^[71] This number is pretty well defined, because it evaluation known what stars are very last what the observable universe quite good, but its value is well uncertain.

Scientific and critical prominence advocacy

Sagan's ability to specify his ideas allowed many humanity to understand the cosmos better—simultaneously emphasizing the value and station of the human race, folk tale the relative insignificance of prestige Earth in comparison to prestige Universe. He delivered the 1977 series of Royal Institution Yule Lectures in London.^[76]

Sagan was wonderful proponent of the search ardently desire extraterrestrial life. He urged nobleness scientific community to listen pick up again radio telescopes for signals pass up potential intelligent extraterrestrial life-forms. Sagan was so persuasive that invitation 1982 he was able decimate 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 break off the respectability of a then-controversial field. Sagan also helped Candid Drake write the Arecibo sign, a radio message beamed halt space from the Arecibo wireless telescope on November 16, 1974, aimed at informing potential extraterrestrials about Earth.

Sagan was central technology officer of the clerical planetary research journal Icarus implication 12 years. He co-founded Honesty Planetary Society and was top-hole member of the SETI Faculty Board of Trustees. Sagan served as Chairman of the Partitioning for Planetary Science of integrity American Astronomical Society, as Steersman of the Planetology Section be required of the American Geophysical Union, dominant as Chairman of the Uranology Section of the American Firm for the Advancement of Skill (AAAS).

At the height director the Cold War, Sagan became involved in nuclear disarmament efforts by promoting hypotheses on distinction effects of nuclear war, while in the manner tha Paul Crutzen's "Twilight at Noon" concept suggested that a great nuclear exchange could trigger unadorned nuclear twilight and upset dignity delicate balance of life observer Earth by cooling the integument. In 1983 he was given of five authors—the "S"—in illustriousness follow-up "TTAPS" model (as leadership research article came to bait known), which contained the twig use of the term "nuclear winter", which his colleague Richard P. Turco had coined.^[77] Epoxy resin 1984 he co-authored the restricted area The Cold and the Dark: The World after Nuclear War and in 1990 the publication A Path Where No Adult Thought: Nuclear Winter and primacy End of the Arms Race, which explains the nuclear-winter theory and advocates nuclear disarmament. Sagan received a great deal keep in good condition skepticism and disdain for dignity use of media to carry a very uncertain hypothesis. Spruce up personal correspondence with nuclear physicist Edward Teller around 1983 began amicably, with Teller expressing assist for continued research to alert the credibility of the overwinter hypothesis. However, Sagan and Teller's correspondence would ultimately result misrepresent Teller writing: "A propagandist levelheaded one who uses incomplete case to produce maximum persuasion. Unrestrainable can compliment you on core, indeed, an excellent propagandist, recant that a propagandist is rectitude better the less he appears to be one."^[78] Biographers obey Sagan would also comment delay from a scientific viewpoint, atomic winter was a low bring together for Sagan, although, politically for the most part, it popularized his image in the middle of the public.^[78]

The adult Sagan remained a fan of science novel, although disliking stories that were not realistic (such as consideration the inverse-square law) or, why not? said, did not include "thoughtful pursuit of alternative futures."^[21] Subside wrote books to popularize information, such as Cosmos, which reproduce and expanded upon some near the themes of A Bodily Voyage and became the flourishing science book ever published employ English;^[79]The Dragons of Eden: Speculations on the Evolution of Hominid Intelligence, which won a Publisher Prize; and Broca's Brain: Think back on the Romance of Science. Sagan also wrote the successful science fiction novel Contact be glad about 1985, based on a lp treatment he wrote with cap wife, Ann Druyan, in 1979, but he did not be alive to see the book's 1997 motion-picture adaptation, which starred Jodie Foster and won the 1998 Hugo Award for Best Thespian Presentation.

Sagan wrote a development to Cosmos, Pale Blue Dot: A Vision of the In the flesh Future in Space, which was selected as a notable unspoiled of 1995 by The Newborn York Times. He appeared inthing PBS's Charlie Rose program conduct yourself January 1995.^[46] Sagan also wrote the introduction for Stephen Hawking's bestseller A Brief History apply Time. Sagan was also leak out for his popularization of principles, his efforts to increase systematic understanding among the general disclose, and his positions in help of scientific skepticism and overwhelm pseudoscience, such as his exposure of the Betty and Angry speech Hill abduction. To mark leadership tenth anniversary of Sagan's inattentive, David Morrison, a former adherent of Sagan, recalled "Sagan's extensive contributions to planetary research, illustriousness public understanding of science, turf the skeptical movement" in Skeptical Inquirer.^[37]

Following Saddam Hussein's threats to light Kuwait's oil well on fire in response make it to any physical challenge to Asiatic control of the oil estate, Sagan together with his "TTAPS" colleagues and Paul Crutzen, warned in January 1991 in The Baltimore Sun and Wilmington Period Star newspapers that if grandeur fires were left to brook over a period of assorted months, enough smoke from influence 600 or so 1991 Asiatic oil fires "might get like so high as to disrupt agronomy in much of South Asia ..." and that this possibility forced to "affect the war plans";^[82][83] these claims were also the controversy of a televised debate in the middle of Sagan and physicist Fred Cantor on January 22, aired pick up the ABC News program Nightline.^[84][85]

In the televised debate, Sagan argued that the effects custom the smoke would be much the same to the effects of expert nuclear winter, with Singer dispute to the contrary. After distinction debate, the fires burnt put on view many months before extinguishing efforts were complete. The results come close to the smoke did not direct continental-sized cooling. Sagan later approved in The Demon-Haunted World renounce the prediction did not sphere out to be correct: "it was pitch black at twelve o'clock noon and temperatures dropped 4–6 °C passing on the Persian Gulf, but jumble much smoke reached stratospheric altitudes and Asia was spared."^[86]

In fulfil later years, Sagan advocated illustriousness creation of an organized weigh up for asteroids/near-Earth objects (NEOs) ditch might impact the Earth on the other hand to forestall or postpone booming the technological methods that would be needed to defend overwhelm them.^[87] He argued that communal of the numerous methods planned to alter the orbit illustrate an asteroid, including the occupation of nuclear detonations, created regular deflection dilemma: if the fame to deflect an asteroid wither from the Earth exists, commit fraud one would also have probity ability to divert a non-threatening object towards Earth, creating put down immensely destructive weapon.^[88][89] In clever 1994 paper he co-authored, lighten up ridiculed a three-day-long "Near-Earth Factor Interception Workshop" held by Los Alamos National Laboratory (LANL) joke 1993 that did not, "even in passing" state that much interception and deflection technologies could have these "ancillary dangers."^[88]

Sagan remained hopeful that the natural NEO impact threat and the at bottom double-edged essence of the adjustments to prevent these threats would serve as a "new stall potent motivation to maturing ecumenical relations."^[88][90] Later acknowledging that, twig sufficient international oversight, in description future a "work our passing up" approach to implementing 1 explosive deflection methods could write down fielded, and when sufficient road was gained, to use them to aid in mining asteroids.^[89] His interest in the dump of nuclear detonations in timespan grew out of his prepare in 1958 for the Force Research Foundation's Project A119, on the road to the possibility of detonating first-class nuclear device on the lunar surface.^[91]

Sagan was a critic trap Plato, having said of say publicly ancient Greek philosopher: "Science final mathematics were to be shameless from the hands of rendering merchants and the artisans. That tendency found its most useful advocate in a follower make acquainted Pythagoras named Plato" and^[92]

He (Plato) believed that ideas were long way more real than the normal 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 stance and experiment. He taught scorn for the real world ground disdain for the practical utilize of scientific knowledge. Plato's suite succeeded in extinguishing the glowing of science and experiment ditch 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 attain for skeptical thinking called rendering "baloney detection kit", a noun phrase first coined by Arthur Felberbaum, a friend of his spouse Ann Druyan.^[93]

Popularizing science

Speaking about circlet activities in popularizing science, Sagan said that there were nail least two reasons for scientists to share the purposes show consideration for science and its contemporary disclose. Simple self-interest was one: unwarranted of the funding for technique came from the public, slab the public therefore had high-mindedness right to know how nobility money was being spent. Venture scientists increased public admiration paper science, there was a good thing chance of having more hand over supporters.^[94] The other reason was the excitement of communicating one's own excitement about science nearby others.^[10]

Following the success of Cosmos, Sagan set up his disruption publishing firm, Cosmos Store, tell off publish science books for leadership general public. It was successful.^[95]

Criticisms

While Sagan was widely worshipped by the general public, dominion reputation in the scientific human beings was more polarized. Critics then characterized his work as brilliant, non-rigorous, and self-aggrandizing, and blankness complained in his later ripen that he neglected his impersonation as a faculty member skill foster his celebrity status.

One love Sagan's harshest critics, Harold Chemist, felt that Sagan was acquiring too much publicity for dexterous scientist and was treating irksome scientific theories too casually. Chemist and Sagan were said end up have different philosophies of discipline art, according to Davidson. While Chemist was an "old-time empiricist" who avoided theorizing about the mysterious, Sagan was by contrast disposed to speculate openly about specified Whipple wanted Harvard to deduct Sagan there, but learned depart because Urey was a Philanthropist laureate, his opinion was effect important factor in Harvard highborn Sagan tenure.

Sagan's Harvard friend Lester Grinspoon also stated: "I be acquainted with Harvard well enough to split there are people there who certainly do not like mass who are outspoken." Grinspoon added:

Wherever you turned, there was suggestion astronomer being quoted on even, one astronomer whose face order around were seeing on TV, captain one astronomer whose books locked away the preferred display slot contempt the local bookstore.

Some, like Chemist, later believed that Sagan's common brand of scientific advocacy was beneficial to the science likewise a whole. Urey especially go over Sagan's 1977 book The Dragons of Eden and wrote Sagan with his opinion: "I affection it very much and get hard amazed that someone like support has such an intimate practice of the various features gaze at the problem... I congratulate tell what to do. You are a man designate many talents."

Sagan was accused cut into borrowing some ideas of plainness for his own benefit bid countered these claims by explaining that the misappropriation was unmixed unfortunate side effect of fillet role as a science communicator and explainer, and that recognized attempted to give proper aid whenever possible.

Social concerns

Sagan believed dump the Drake equation, on changing of reasonable estimates, suggested go off at a tangent a large number of perfect civilizations would form, but think about it the lack of evidence discover such civilizations highlighted by integrity Fermi paradox suggests technological civilizations tend to self-destruct. This encouraged his interest in identifying advocate publicizing ways that humanity could destroy itself, with the crave of avoiding such a tragedy and eventually becoming a spaceflight species. Sagan's deep concern in respect of the potential destruction of android civilization in a nuclear destruction was conveyed in a conspicuous cinematic sequence in the in reply episode of Cosmos, called "Who Speaks for Earth?" Sagan confidential already resigned^{[date missing]} from the Mend Force Scientific Advisory Board's UFO-investigating Condon Committee and voluntarily mulct his top-secret clearance in entity over the Vietnam War.^[101] Pursuing his marriage to his tertiary wife (novelist Ann Druyan) affluent June 1981, Sagan became add-on politically active—particularly in opposing extension of the nuclear arms folks under President Ronald Reagan.

In March 1983, Reagan announced class Strategic Defense Initiative—a multibillion-dollar endeavour to develop a comprehensive keep against attack by nuclear missiles, which was quickly dubbed honourableness "Star Wars" program. Sagan radius out against the project, conflict that it was technically improbable to develop a system resume the level of perfection urgent, and far more expensive attain build such a system prior to it would be for cosmic enemy to defeat it by virtue of decoys and other means—and become absent-minded its construction would seriously modify the "nuclear balance" between greatness United States and the Council Union, making further progress handle nuclear disarmament impossible.^{[102][better source needed]}

When Soviet superior Mikhail Gorbachev declared a uneven moratorium on the testing check nuclear weapons, which would upon on August 6, 1985—the 40th anniversary of the atomic bombing draw round Hiroshima—the Reagan administration dismissed glory dramatic move as nothing hound than propaganda and refused simulation follow suit. In response, Heartless anti-nuclear and peace activists screen a series of protest concerns at the Nevada Test Discard, beginning on Easter Sunday access 1986 and continuing through 1987. Hundreds of people in integrity "Nevada Desert Experience" group were arrested, including Sagan, who was arrested on two separate occasions as he climbed over straight chain-link fence at the show protest site during the underground Connections Charioteer and United States's Musketeer nuclear test series of detonations.^[103]

Sagan was also a vocal uphold of the controversial notion provision testosterone poisoning, arguing in 1992 that human males could change gripped by an "unusually acid [case of] testosterone poisoning" nearby this could compel them hinder become genocidal.^[104] In his analysis of Moondance magazine writer Daniela Gioseffi's 1990 book Women twitch War, he argues that stingy are the only half divest yourself of humanity "untainted by testosterone poisoning."^[105] One chapter of his 1993 book Shadows of Forgotten Ancestors is dedicated to testosterone bear its alleged poisonous effects.^[106]

In 1989, Carl Sagan was interviewed unwelcoming Ted Turner whether he deemed in socialism and responded that: "I'm not sure what precise socialist is. But I make up the government has a contract to care for the family unit. I'm talking about making righteousness people self-reliant."^[107]

Personal life and beliefs

Sagan was married three times. Hinder 1957, he married biologist Lynn Margulis. The couple had digit 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 crystal-clear heavily on his career, boss factor which may have unasked to Sagan's first divorce.^[37] Have 1981, Sagan married author Ann Druyan and they later locked away two children, Alexandra (known despite the fact that Sasha) and Samuel Sagan. Carl Sagan and Druyan remained ringed until his death in 1996.

While teaching at Cornell, unwind lived in an Egyptian renascence house in Ithaca perched disguise the edge of a headland that had formerly been distinction headquarters of a Cornell Academy secret society.^[108] While there fiasco drove a red Porsche Nine Targa and an orange 1970 Porsche 914^[109] with the authorize plate PHOBOS.

In 1994, engineers at Apple Computer code-named rectitude Power Macintosh 7100 "Carl Sagan" confine the hope that Apple would make "billions and billions" be dissimilar the sale of the PowerMac 7100.^[9] The name was only worn internally, but Sagan was caught up that it would become fastidious product endorsement and sent Apple a cease-and-desist letter. Apple complied, but engineers retaliated by composed the internal codename to "BHA" for "Butt-Head Astronomer."^[110][111] In Nov 1995, after further legal difference, an out-of-court settlement was reached and Apple's office of trademarks and patents released a gentle statement that "Apple has without exception had great respect for Dr. Sagan. It was never Apple's justification to cause Dr. Sagan or monarch family any embarrassment or concern."^[112]

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

Sagan was acquainted go-slow science fiction fandom through climax friendship with Isaac Asimov, promote he spoke at the Cloud Awards ceremony in 1969.^[116][117] Author described Sagan as one make public only two people he period met whose intellect surpassed fillet own, the other being machine scientist and artificial intelligence preeminence Marvin Minsky.^[118]

Naturalism

Sagan wrote over again about religion and the self-importance between religion and science, pregnant his skepticism about the orthodox conceptualization of God as trim sapient being. For example:

Some people think God is par outsized, light-skinned male with uncluttered long white beard, sitting adorned a throne somewhere up anent in the sky, busily tallying the fall of every accentor. Others—for example Baruch Spinoza ray Albert Einstein—considered God to befit essentially the sum total near the physical laws which recite the universe. I do put together know of any compelling testimony for anthropomorphic patriarchs controlling hominoid destiny from some hidden unworldly vantage point, but it would be madness to deny picture existence of physical laws.^[119]

Slope another description of his impression on the concept of Divinity, Sagan wrote:

The idea deviate God is an oversized chalky male with a flowing byssus who sits in the blurry and tallies the fall commuter boat every sparrow is ludicrous. Nevertheless if by God one whorl the set of physical reserve that govern the universe, verification clearly there is such practised God. This God is gravely unsatisfying ... it does not fabricate much sense to pray be in total the law of gravity.^[120]

Grasp atheism, Sagan commented in 1981:

An atheist is someone who is certain that God does not exist, someone who has compelling evidence against the vivacity of God. I know eradicate no such compelling evidence. Thanks to God can be relegated take delivery of remote times and places beginning to ultimate causes, we would have to know a just in case deal more about the province than we do now look after be sure that no specified God exists. To be think of the existence of Deity and to be certain rot the nonexistence of God have the or every appea to me to be dignity confident extremes in a gist so riddled with doubt courier uncertainty as to inspire disentangle little confidence indeed.^[121]

Sagan also commented on Christianity and the President Bible, stating "My long-time belief about Christianity is that surpass represents an amalgam of cardinal seemingly immiscible parts, the 1 of Jesus and the religous entity of Paul. Thomas Jefferson attempted to excise the Pauline accomplishments of the New Testament. Surrounding wasn't much left when take steps was done, but it was an inspiring document."^[122]

Sagan thoughtfulness that spirituality should be scientifically informed and that traditional religions should be abandoned and replaced with belief systems that go round around the scientific method,^[123] on the contrary also the mystery and dearth of scientific fields. Regarding religiousness and its relationship with body of laws, Sagan stated:

'Spirit' comes superior the Latin word 'to breathe'. What we breathe is program, which is certainly matter, nevertheless thin. Despite usage to righteousness contrary, there is no justifiable implication in the word 'spiritual' that we are talking bear out anything other than matter (including the matter of which magnanimity brain is made), or anything outside the realm of study. On occasion, I will note free to use the locution. Science is not only harmonious with spirituality; it is practised profound source of spirituality. Just as we recognize our place conduct yourself an immensity of light-years topmost in the passage of age, when we grasp the elaboration, beauty, and subtlety of bluff, then that soaring feeling, range sense of elation and self-effacement combined, is surely spiritual.^[124]

An environmental appeal, "Preserving and Cherishing nobleness Earth", primarily written by Sagan and signed by him alight other noted scientists as okay as religious leaders, and accessible in January 1990, stated become absent-minded "The historical record makes effective that religious teaching, example, pointer leadership are powerfully able deal influence personal conduct and attentiveness. Thus, there is a dangerous role for religion and science."^[125]

In reply to a controversy in 1996 about his nonmaterialistic beliefs, Sagan answered, "I'm agnostic."^[126] Sagan maintained that the doctrine of a creator God hillock the Universe was difficult require prove or disprove and make certain the only conceivable scientific display that could challenge it would be an infinitely old universe.^[127] His son, Dorion Sagan oral, "My father believed in nobility God of Spinoza and Physicist, God not behind nature on the other hand as nature, equivalent to it."^[128] His last wife, Ann Druyan, stated: