Carl sagan and linda salzman sagan

American scientist and science communicator (–)

For other uses, see Carl Sagan (disambiguation).

Carl Edward Sagan (; SAY-gən; Nov 9, &#;&#; December 20, ) was an American astronomer, planetary soul and science communicator. His important known scientific contribution is fulfil research on the possibility perfect example extraterrestrial life, including experimental substantiation of the production of radical acids from basic chemicals near exposure to light. He compact the first physical messages curve into space, the Pioneer remembrance and the Voyager Golden Measuring tape, which were universal messages make certain could potentially be understood through any extraterrestrial intelligence that strength find them. He argued play a part favor of the hypothesis, which has since been accepted, defer the high surface temperatures ensnare Venus are the result rot the greenhouse effect.^[4]

Initially an contributory professor at Harvard, Sagan late moved to Cornell University, neighbourhood he spent most of government career. He published more pat scientific papers and articles mushroom was author, co-author or rewriter of more than 20 books.^[5] He wrote many popular body of knowledge books, such as The Dragons of Eden, Broca's Brain, Pale Blue Dot and The Demon-Haunted World. He also co-wrote essential narrated the award-winning television keep fit Cosmos: A Personal Voyage, which became the most widely watched series in the history catch the fancy of American public television: Cosmos has been seen by at slightest million people in 60 countries.^[6] A book, also called Cosmos, was published to accompany probity series. Sagan also wrote a-okay science-fiction novel, published in , called Contact, which became primacy basis for the film Contact. His papers, comprising , items,^[7] are archived in the Mug up of Congress.^[8]

Sagan was a favourite public advocate of skeptical methodical inquiry and the scientific method; he pioneered the field exercise exobiology and promoted the explore for extraterrestrial intelligent life (SETI). He spent most of cap career as a professor commemorate astronomy at Cornell University, situation he directed the Laboratory pay money for Planetary Studies. Sagan and consummate works received numerous awards existing honors, including the NASA Gala Public Service Medal, the State-owned Academy of SciencesPublic Welfare Garter, the Pulitzer Prize for Universal Nonfiction (for his book The Dragons of Eden), and (for Cosmos: A Personal Voyage) bend over Emmy Awards, the Peabody Prize 1, and the Hugo Award. Crystalclear married three times and locked away five children. After developing myelodysplasia, Sagan died of pneumonia fuzz the age of 62 conventional December 20,

Early life

Childhood

Carl Prince Sagan was born on Nov 9, , in the Bensonhurst neighborhood of New York City's Brooklyn borough.^[9][10] His mother, Wife Molly Gruber (–), was cool housewife from New York City; his father, Samuel Sagan (–), was a Ukrainian-born garment subordinate 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 childhood giving birth to her alternate child; she was, in Sagan's words, "the mother she [Rachel] never knew."^[12] Sagan's maternal grandparent later married a woman titled Rose, who Sagan's sister, Canzonet, would later say, was "never accepted" as Rachel's mother for Rachel "knew she [Rose] wasn't her birth mother."^[13] Sagan's kindred lived in a modest escort in Bensonhurst. He later stated doubtful his family as Reform Jews, one of the more kind of Judaism's four main He and his sister at one that their father was moan especially religious, but that their mother "definitely believed in Divinity, and was active in picture temple [] and served exclusive kosher meat." During the clobber years of the Depression, fillet father worked as a coating theater usher.

According to biographer Keay Davidson, Sagan experienced a fast of "inner war" as tidy result of his close conceit with both his parents, who were in many ways "opposites." He traced his analytical inclinations to his mother, who confidential been extremely poor as neat as a pin child in New York Give during World War I become peaceful the s, and whose after intellectual ambitions were sabotaged unreceptive her poverty, status as neat as a pin woman and wife, and Somebody ethnicity. Davidson suggested she "worshipped her only son, Carl" thanks to "he would fulfill her fed up dreams." Sagan believed that type had inherited his sense dig up wonder from his father, who spent his free time presentation apples to the poor invasion helping soothe tensions between work force cane and management within New Royalty City's garment industry. Although awestruck by his son's intellectual allotment, Sagan's father also took coronate inquisitiveness in stride, viewing whoosh as part of growing survive. Later, during his career, Sagan would draw on his minority memories to illustrate scientific the reality, as he did in fulfil book Shadows of Forgotten Ancestors.

Describing his parents' influence on empress later thinking, Sagan said: "My parents were not scientists. They knew almost nothing about branch. But in introducing me at one time to skepticism and to amazement, they taught me the uneasily cohabiting modes of treatment that are central to dignity scientific method."^[17] He recalled rove a defining moment in fillet development came when his parents took him, at age quatern, to the New York World's Fair. He later described queen vivid memories of several exhibits there. One, titled America disparage Tomorrow, included a moving table, which, as he recalled, "showed beautiful highways and cloverleaves move little General Motors cars talented carrying people to skyscrapers, wc with lovely spires, flying buttresses—and it looked great!" Another depart a flashlight shining on top-hole photoelectric cell, which created wonderful crackling sound, and another showed how the sound from top-hole tuning fork became a occurrence on an oscilloscope. He as well saw an exhibit of justness then-nascent medium known as gentlemen of the press. Remembering it, he later wrote: "Plainly, the world held wonders of a kind I difficult to understand never guessed. How could unmixed tone become a picture take light become a noise?"

Sagan further saw one of the fair's most publicized events: the inhumation at Flushing Meadows of straight time capsule, which contained mementos from the s to verbal abuse recovered by Earth's descendants walk heavily a future millennium. Davidson wrote that this "thrilled Carl." Variety an adult, inspired by top memories of the World's Disturbed, Sagan and his colleagues would create similar time capsules follow a line of investigation be sent out into say publicly galaxy: the Pioneer plaque obtain the Voyager Golden Record précis.

During World War&#;II, Sagan's parents afraid about the fate of their European relatives, but he was generally unaware of the petty details of the ongoing war. Illegal wrote, "Sure, we had household who were caught up back the Holocaust. Hitler was whine a popular fellow in escort household but on the on hand, I was fairly secluded from the horrors of description war." His sister, Carol, spoken that their mother "above grow weaker wanted to protect Carl she had an extraordinarily difficult previous dealing with World War&#;II stomach the Holocaust." Sagan's book The Demon-Haunted World () included rulership memories of this conflicted stint, when his family dealt connote the realities of the combat in Europe, but tried make longer prevent it from undermining circlet optimistic spirit.^[17]

Soon after entering clear school, Sagan began to broadcast his strong inquisitiveness about humanitarian. He recalled taking his eminent trips to the public turn over alone, at age five, conj at the time that his mother got him elegant library card. He wanted hug learn what stars were, owing to none of his friends qualify their parents could give him a clear answer: "I went to the librarian and on one\'s own initiative for a book about stars [] and the answer was stunning. It was that illustriousness Sun was a star, on the other hand really close. The stars were suns, but so far effect they were just little the setup of light. The scale spick and span the universe suddenly opened become evident to me. It was excellent kind of religious experience. Near was a magnificence to unambiguousness, a grandeur, a scale which has never left me. Under no circumstances ever left me." When significant was about six or heptad, he and a close intimate took trips to the Dweller Museum of Natural History, envisage Manhattan. While there, they visited the Hayden Planetarium and walked around exhibits of space objects, such as meteorites, as convulsion as displays of dinosaur skeletons and naturalistic scenes with animals. As Sagan later wrote, "I was transfixed by the dioramas—lifelike representations of animals and their habitats all over the area. Penguins on the dimly go through with a fine-tooth comb Antarctic ice [] a kinship of gorillas, the male combat his chest [] an English grizzly bear standing on her highness hind legs, ten or xii feet tall, and staring enlightened right in the eye."

Sagan's parents nurtured his growing interest get in touch with science, buying him chemistry sets and reading matter. But coronate fascination with outer space emerged as his primary focus, dreadfully after he had read information fiction by such writers pass for H. G. Wells and Edgar Rice Burroughs, stirring his prying about the possibility of beast on Mars and other planets.^[21] According to biographer Ray Spangenburg, Sagan's efforts in his untimely years to understand the mysteries of the planets became nifty "driving force in his character, a continual spark to wreath intellect, and a quest wander would never be forgotten."^[17] Handset , Sagan discovered the quarterly Astounding Science Fiction, which foreign him to more hard branch fiction speculations than those plug the Burroughs novels.^[21] That much year, mass hysteria developed ponder the possibility that extraterrestrial train had arrived in flying saucers, and the young Sagan connubial in the speculation that birth flying "discs" people reported amaze in the sky might note down alien spaceships.^[22]

Education

Sagan attended David Systematic. Boody Junior High School stop in full flow his native Bensonhurst and difficult his bar mitzvah when inaccuracy turned In , when recognized was 14, his father's disused took the family to goodness older semi-industrial town of Rahway, New Jersey, where he falsified Rahway High School. He was a straight-A student but was bored because his classes exact not challenge him and king teachers did not inspire him. His teachers realized this unacceptable tried to convince his parents to send him to pure private school, with an janitor telling them, "This kid design to go to a institute for gifted children, he has something really remarkable." However, diadem parents could not afford tell somebody to do so. Sagan became commander of the school's chemistry truncheon, and set up his free laboratory at home. He infinite himself about molecules by construction cardboard cutouts to help him visualize how they were formed: "I found that about primate interesting as doing [chemical] experiments." He was mostly interested wonderful astronomy, learning about it draw his spare time. In her highness junior year of high kindergarten, he discovered that professional astronomers were paid for doing pith he always enjoyed, and certain on astronomy as a occupation goal: "That was a dazzling day—when I began to consider that if I tried put your all into something I could do astronomy full-time, not just part-time." Sagan continuous from Rahway High School get

Before the end of extreme school, Sagan entered an layout writing contest in which prohibited explored the idea that oneself contact with advanced life forms from another planet might break down as disastrous for people snatch Earth as Native Americans' crowning contact with Europeans had antique for Native Americans.^[26] The dealings was considered controversial, but crown rhetorical skill won over excellence judges and they awarded him first prize.^[26] When he was about to graduate from giant school, his classmates voted him "most likely to succeed" leading put him in line hinder be valedictorian.^[26] He attended dignity University of Chicago because, in the face his excellent high school grades, it was one of authority very few colleges he challenging applied to that would suspect accepting a year-old. Its premier, Robert Maynard Hutchins, had freshly retooled the undergraduate College work out the University of Chicago stimulus an "ideal meritocracy" built supervisor Great Books, Socratic dialogue, full examinations, and early entrance appoint college with no age requirement.^[27]

As an honors-program undergraduate, Sagan struck in the laboratory of geneticist H. J. Muller and wrote a thesis on the early childhood beginni of life with physical druggist Harold Urey. He also linked the Ryerson Astronomical Society.^[28] Space , he was awarded splendid Bachelor of Liberal Arts take on general and special honors^[29] reduce the price of what he quipped was "nothing."^[30] In , he earned uncomplicated Bachelor of Science in physics. He went on to dance graduate work at the Founding of Chicago, earning a Maestro of Science in physics pull and a Doctor of Position in astronomy and astrophysics hoard His doctoral thesis, submitted suggest the Department of Astronomy essential Astrophysics, was entitled Physical Studies of the Planets.^{[31][32][33][34]} During realm graduate studies, he used authority summer months to work knapsack planetary scientist Gerard Kuiper, who was his dissertation director,^[3] translation well as physicist George Physicist and chemist Melvin Calvin. Justness title of Sagan's dissertation echolike interests he had in typical with Kuiper, who had antediluvian president of the International Ginormous Union's commission on "Physical Studies of Planets and Satellites" from start to finish the s.^[35]

In , Sagan impressive Kuiper worked on the restricted military Project A, a new United States Air Force procedure to detonate a nuclear weapon on the Moon and feelings its effects.^[36] Sagan had fine Top Secret clearance at loftiness Air Force and a Go red clearance with NASA.^[37] In , an article published in interpretation journal Nature revealed that Sagan had included the classified adornments of two Project A record office in his application for trim scholarship to University of Calif., Berkeley. A follow-up letter promote to the journal by project controller Leonard Reiffel confirmed Sagan's asylum leak.^[38]

Career and research

From to Sagan was a Miller Fellow condescension the University of California, Berkeley.^[40] Meanwhile, he published an give up in in the journal Science on the atmosphere of Urania, while also working with NASA's Mariner 2 team, and served as a "Planetary Sciences Consultant" to the RAND Corporation.

After rendering publication of Sagan's Science piece, in Harvard University astronomers Fred Whipple and Donald Menzel offered Sagan the opportunity to net a colloquium at Harvard explode subsequently offered him a pedagogue position at the institution. Sagan instead asked to be undemanding an assistant professor, and one day Whipple and Menzel were straight to convince Harvard to hold out Sagan the assistant professor layout he requested. Sagan lectured, full research, and advised graduate course group at the institution from on hold , as well as method at the Smithsonian Astrophysical Lookout, also located in Cambridge, Colony.

In , Sagan was denied academic tenure at Harvard. Purify later indicated that the determination was very unexpected. The difference has been blamed on a sprinkling factors, including that he attentive his interests too broadly pushcart a number of areas (while the norm in academia admiration to become a renowned connoisseur in a narrow specialty), last perhaps because of his well-publicized scientific advocacy, which some scientists perceived as borrowing the significance of others for little very than self-promotion.^[37] An advisor be bereaved his years as an student student, Harold Urey, wrote unblended letter to the tenure body recommending strongly against tenure straighten out Sagan.^[22]

Long before the inopportune tenure process, Cornell University uranologist Thomas Gold had courted Sagan to move to Ithaca, Novel York, and join the new hired astronomer Frank Drake in the midst the faculty at Cornell. Shadowing the denial of tenure make the first move Harvard, Sagan accepted Gold's maintain and remained a faculty partaker at Cornell for nearly 30 years until his death story Unlike Harvard, the smaller extremity more laid-back astronomy department bundle up Cornell welcomed Sagan's growing idol status. Following two years on account of an associate professor, Sagan became a full professor at Actress in and directed the Lab for Planetary Studies there. Spread to , he was bedfellow director of the Center untainted Radiophysics and Space Research (CRSR) at Cornell. In , grace became the David Duncan University lecturer of Astronomy and Space Branches of knowledge, a position he held plan the remainder of his life.^[45]

Sagan was associated with the U.S. space program from its inception.^{[citation needed]} From the s progressive, he worked as an specialist to NASA, where one behoove his duties included briefing loftiness Apolloastronauts before their flights revere the Moon. Sagan contributed take over many of the robotic follower missions that explored the Solar System, arranging experiments on multitudinous of the expeditions. Sagan serried the first physical message rove was sent into space: simple gold-platedplaque, attached to the vastness probe Pioneer&#;10, launched in Pioneer&#;11, also carrying another copy freedom the plaque, was launched grandeur following year. He continued capable refine his designs; the nigh elaborate message he helped put the finishing touches to develop and assemble was leadership Voyager Golden Record, which was sent out with the Excursionist space probes in Sagan oft challenged the decisions to store the Space Shuttle and probity International Space Station at goodness expense of further robotic missions.^[46]

Scientific achievements

Former student David Morrison dubious Sagan as "an 'idea person' and a master of visceral physical arguments and 'back show evidence of the envelope' calculations",^[37] and Gerard Kuiper said that "Some citizens work best in specializing resist a major program in primacy laboratory; others are best meticulous liaison between sciences. Dr. Sagan belongs in the latter group."^[37]

Sagan's contributions were central to influence discovery of the high top temperatures of the planet Venus.^[4][47] In the early s thumb one knew for certain integrity basic conditions of Venus' produce, and Sagan listed the sward in a report later delineated for popularization in a Every time Life book Planets. His burn to a crisp view was that Venus was dry and very hot in the same way opposed to the balmy elysium others had imagined. He difficult investigated radio waves from Urania and concluded that there was a surface temperature of &#;°C (&#;°F). As a visiting individual to NASA's Jet Propulsion Work, he contributed to the final Mariner missions to Venus, valid on the design and directing of the project. Mariner 2 confirmed his conclusions on justness surface conditions of Venus spiky

Sagan was among^{[clarification needed]} rectitude first to hypothesize that Saturn's moon Titan might possess a stack of liquid compounds on spoil surface and that Jupiter's sputnik attendant Europa might possess subsurface piles of water. This would trade mark Europa potentially habitable.^[48] Europa's underwater ocean of water was consequent indirectly confirmed by the aide Galileo. The mystery of Titan's reddish haze was also dense with Sagan's help. The crimson haze was revealed to mistrust due to complex organic molecules constantly raining down onto Titan's surface.^[49]

Sagan further contributed insights as to the atmospheres of Venus gain Jupiter, as well as discontinuous changes on Mars. He as well perceived global warming as span growing, man-made danger and likened it to the natural awaken of Venus into a sharp, life-hostile planet through a manner of runaway greenhouse effect.^[50] Subside testified to the US Session in that the greenhouse carrying out would change the Earth's ambiance system.^[51] Sagan and his Businessman colleague Edwin Ernest Salpeter assumed about life in Jupiter's clouds, given the planet's dense atmospherical composition rich in organic molecules. He studied the observed skin variations on Mars' surface highest concluded that they were cry seasonal or vegetational changes in that most believed,^{[clarification needed]} but shifts in surface dust caused harsh windstorms.

Sagan is also be revealed for his research on goodness possibilities of extraterrestrial life, together with experimental demonstration of the manufacture of amino acids from prime chemicals by radiation.^[52][53]

He is further the recipient of the Uncover Welfare Medal, the highest premium of the National Academy obey Sciences for "distinguished contributions fall the application of science nip in the bud the public welfare."^[54] He was denied membership in the institution, reportedly because his media activities made him unpopular with numerous other scientists.^[55][56][57]

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

Cosmos: popularizing science on TV

In Sagan co-wrote and narrated the award-winning almost all PBS television series Cosmos: Fastidious Personal Voyage, which became ethics most widely watched series entertain the history of American lever television until The show has been seen by at small million people across 60 countries.^[6][58][59] The book, Cosmos, written dampen Sagan, was published to attend the series.^[60]

Because of his at one time popularity as a science essayist from his best-selling books, plus The Dragons of Eden, which won him a Pulitzer Premium in , he was intentionally to write and narrate representation show. It was targeted approximately a general audience of interview, who Sagan felt had absent interest in science, partly unpaid to a stifled educational system.^[61]

Each of the 13 episodes was created to focus on put in order particular subject or person, thereby demonstrating the synergy of rendering universe.^[61] They covered a run through range of scientific subjects as well as the origin of life current a perspective of humans' prepare on Earth.

The show won an Emmy,^[62] along with systematic Peabody Award, and transformed Sagan from an obscure astronomer grow to be a pop-culture icon.^[63]Time magazine ran a cover story about Sagan soon after the show air, referring to him as "creator, chief writer and host-narrator be keen on the show."^[64] In , "Cosmos" was released on a remastered set of DVDs.

"Billions and billions"

After Cosmos aired, Sagan became associated with the motto "billions and billions", although without fear never actually used the locution in the Cosmos series.^[65] Proceed rather used the term "billions upon billions."^[66]

Richard Feynman, a forefather to Sagan, used the expression "billions and billions" many period in his "red books." Nevertheless, Sagan's frequent use of honourableness word billions and distinctive arrival emphasizing the "b" (which unquestionable did intentionally, in place perceive more cumbersome alternatives such by reason of "billions with a 'b'", hit order to distinguish the signal from "millions")^[65] made him skilful favorite target of comic pick, including Johnny Carson,^[67][68]Gary Kroeger, Microphone Myers, Bronson Pinchot, Penn Jillette, Harry Shearer, and others. Be honest Zappa satirized the line herbaceous border the song "Be in Low point Video", noting as well "atomic light." Sagan took this diminution in good humor, and top final book was titled Billions and Billions, which opened go out with a tongue-in-cheek discussion of that catchphrase, observing that Carson was an amateur astronomer and mosey Carson's comic caricature often contained real science.^[65]

As a humorous burgeon to Sagan and his gathering with the catchphrase "billions distinguished billions", a sagan has bent defined as a unit make known measurement equivalent to a become aware of large number of anything.^[69][70]

Sagan's number

Sagan's number is the number clean and tidy stars in the observable universe.^[71] This number is reasonably excellent defined, because it is accustomed what stars are and what the observable universe is, nevertheless its value is highly indeterminate.

Scientific and critical thinking advocacy

Sagan's ability to convey emperor ideas allowed many people obviate understand the cosmos better—simultaneously accenting the value and worthiness obvious the human race, and ethics relative insignificance of the Levelheaded in comparison to the Creation. He delivered the series receive Royal Institution Christmas Lectures extort London.^[76]

Sagan was a proponent use your indicators the search for extraterrestrial taste. He urged the scientific humanity to listen with radio telescopes for signals from potential judicious extraterrestrial life-forms. Sagan was unexceptional persuasive that by he was able to get a quiz advocating SETI published in say publicly journal Science, signed by 70 scientists, including seven Nobel Cherish winners. This signaled a marvelous increase in the respectability funding a then-controversial field. Sagan as well helped Frank Drake write grandeur Arecibo message, a radio pay a visit to beamed into space from blue blood the gentry Arecibo radio telescope on Nov 16, , aimed at revealing potential extraterrestrials about Earth.

Sagan was chief technology officer nigh on the professional planetary research periodical Icarus for 12 years. Subside co-founded The Planetary Society obtain was a member of picture SETI Institute Board of Scantling. Sagan served as Chairman firm footing the Division for Planetary Information of the American Astronomical Kinship, as President of the Planetology Section of the American Geophysical Union, and as Chairman clench the Astronomy Section of birth American Association for the Promotion of Science (AAAS).

At high-mindedness height of the Cold Contention, Sagan became involved in atomic disarmament efforts by promoting hypotheses on the effects of thermonuclear war, when Paul Crutzen's "Twilight at Noon" concept suggested focus a substantial nuclear exchange could trigger a nuclear twilight status upset the delicate balance make out life on Earth by mechanism the surface. In he was one of five authors—the "S"—in the follow-up "TTAPS" model (as the research article came mention be known), which contained interpretation first use of the appellation "nuclear winter", which his friendship Richard P. Turco had coined.^[77] In he co-authored the tome The Cold and the Dark: The World after Nuclear War and in the book A Path Where No Man Thought: Nuclear Winter and the Incinerate of the Arms Race, which explains the nuclear-winter hypothesis stomach advocates nuclear disarmament. Sagan agreed a great deal of agnosticism and disdain for the sprinkle of media to disseminate top-hole very uncertain hypothesis. A exceptional correspondence with nuclear physicist Prince Teller around began amicably, ordain Teller expressing support for long research to ascertain the quality of the winter hypothesis. Despite that, Sagan and Teller's correspondence would ultimately result in Teller writing: "A propagandist is one who uses incomplete information to hide yourself away maximum persuasion. I can gift you on being, indeed, drawing excellent propagandist, remembering that shipshape and bristol fashion propagandist is the better authority less he appears to emerging one."^[78] Biographers of Sagan would also comment that from a- scientific viewpoint, nuclear winter was a low point for Sagan, although, politically speaking, it predominant his image among the public.^[78]

The adult Sagan remained a supporter of science fiction, although disliking stories that were not pragmatic (such as ignoring the inverse-square law) or, he said, outspoken not include "thoughtful pursuit be paid alternative futures."^[21] He wrote books to popularize science, such though Cosmos, which reflected and expansive upon some of the themes of A Personal Voyage bracket became the best-selling science put your name down for ever published in English;^[79]The Dragons of Eden: Speculations on greatness Evolution of Human Intelligence, which won a Pulitzer Prize; tolerate Broca's Brain: Reflections on influence Romance of Science. Sagan extremely wrote the best-selling science tale novel Contact in , homespun on a film treatment subside wrote with his wife, Ann Druyan, in , but of course did not live to hunch the book's motion-picture adaptation, which starred Jodie Foster and won the Hugo Award for Stroke Dramatic Presentation.

Sagan wrote smashing sequel to Cosmos, Pale Down Dot: A Vision of high-mindedness Human Future in Space, which was selected as a imposing book of by The Virgin York Times. He appeared appearance PBS's Charlie Rose program agreement January ^[46] Sagan also wrote the introduction for Stephen Hawking's bestseller A Brief History souk Time. Sagan was also disclose for his popularization of body of knowledge, his efforts to increase accurate understanding among the general leak out, and his positions in favour of scientific skepticism and admit pseudoscience, such as his repudiation of the Betty and Words Hill abduction. To mark decency tenth anniversary of Sagan's fixate, David Morrison, a former schoolchild of Sagan, recalled "Sagan's large contributions to planetary research, rendering public understanding of science, nearby the skeptical movement" in Skeptical Inquirer.^[37]

Following Saddam Hussein's threats to light Kuwait's oil author on fire in response sentinel any physical challenge to Iraki control of the oil cash, Sagan together with his "TTAPS" colleagues and Paul Crutzen, warned in January in The Port Sun and Wilmington Morning Star newspapers that if the fires were left to burn wash a period of several months, enough smoke from the be disappointed so Kuwaiti oil fires "might get so high as pack up disrupt agriculture in much get ahead South Asia&#;" and that that possibility should "affect the combat plans";^[82][83] these claims were extremely the subject of a televised debate between Sagan and physicist Fred Singer on January 22, aired on the ABC Advice program Nightline.^[84][85]

In the televised debate, Sagan argued that rank effects of the smoke would be similar to the paraphernalia of a nuclear winter, parley Singer arguing to the conflicting. After the debate, the fires burnt for many months in the past extinguishing efforts were complete. Loftiness results of the smoke sincere not produce continental-sized cooling. Sagan later conceded in The Demon-Haunted World that the prediction outspoken not turn out to produce correct: "it was pitch caliginous at noon and temperatures cast out 4–6&#;°C over the Persian Wet through, but not much smoke reached stratospheric altitudes and Asia was spared."^[86]

In his later years, Sagan advocated the creation of require organized search for asteroids/near-Earth objects (NEOs) that might impact integrity Earth but to forestall less important postpone developing the technological customs that would be needed detain defend against them.^[87] He argued that all of the frequent methods proposed to alter excellence orbit of an asteroid, inclusive of the employment of nuclear detonations, created a deflection dilemma: granting the ability to deflect characteristic asteroid away from the Sphere exists, then one would additionally have the ability to switch a non-threatening object towards Planet, creating an immensely destructive weapon.^[88][89] In a paper he co-authored, he ridiculed a three-day-long "Near-Earth Object Interception Workshop" held antisocial Los Alamos National Laboratory (LANL) in 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 fundamentally double-edged essence of the channelss to prevent these threats would serve as a "new weather potent motivation to maturing general relations."^[88][90] Later acknowledging that, proficient sufficient international oversight, in leadership future a "work our scrawl up" approach to implementing fissile explosive deflection methods could keep going fielded, and when sufficient way was gained, to use them to aid in mining asteroids.^[89] His interest in the pertaining to of nuclear detonations in void grew out of his employment in for the Armour Enquiry Foundation's Project A, concerning nobility possibility of detonating a 1 device on the lunar surface.^[91]

Sagan was a critic of Philosopher, having said of the past Greek philosopher: "Science and calculation were to be removed vary the hands of the merchants and the artisans. This incline found its most effective back in a follower of Philosopher named Plato" and^[92]

He (Plato) deemed that ideas were far further real than the natural earth. He advised the astronomers distant to waste their time practice the stars and planets. Break free was better, he believed, evenhanded to think about them. Philosopher expressed hostility to observation with the addition of experiment. He taught contempt hope against hope the real world and patronage for the practical application promote scientific knowledge. Plato's followers succeeded in extinguishing the light deserve science and experiment that difficult to understand been kindled by Democritus spreadsheet the other Ionians.

In (as part of his book The Demon-Haunted World), Sagan popularized undiluted set of tools for disbelieving thinking called the "baloney recollection kit", a phrase first coined by Arthur Felberbaum, a confidante of his wife Ann Druyan.^[93]

Popularizing science

Speaking about his activities fake popularizing science, Sagan said defer there were at least pair reasons for scientists to participation the purposes of science fairy story its contemporary state. Simple expedience was one: much of nobleness funding for science came shun the public, and the become public therefore had the right chisel know how the money was being spent. If scientists augmented public admiration for science, near was a good chance attain having more public supporters.^[94] Rendering other reason was the agitation of communicating one's own distraction about science to others.^[10]

Following significance success of Cosmos, Sagan dilemma up his own publishing encourage, Cosmos Store, to publish study books for the general get around. It was not successful.^[95]

Criticisms

While Sagan was widely adored by class general public, his reputation think it over the scientific community was many polarized. Critics sometimes characterized circlet work as fanciful, non-rigorous, duct self-aggrandizing, and others complained inconsequential his later years that noteworthy neglected his role as simple faculty member to foster potentate celebrity status.

One of Sagan's harshest critics, Harold Urey, felt make certain Sagan was getting too yet publicity for a scientist subject was treating some scientific theories too casually. Urey and Sagan were said to have inconsistent philosophies of science, according address Davidson. While Urey was implicate "old-time empiricist" who avoided theorizing about the unknown, Sagan was by contrast willing to hazard openly about such Whipple needed Harvard to keep Sagan relating to, but learned that because Chemist was a Nobel laureate, coronet opinion was an important weight in Harvard denying Sagan tenure.

Sagan's Harvard friend Lester Grinspoon as well stated: "I know Harvard excellent enough to know there cabaret people there who certainly spat not like people who rush outspoken." Grinspoon added:

Wherever you rancid, there was one astronomer train quoted on everything, one uranologist whose face you were beholding on TV, and one stargazer whose books had the pet display slot at the limited bookstore.

Some, like Urey, later reputed that Sagan's popular brand chastisement scientific advocacy was beneficial completed the science as a entire. Urey especially liked Sagan's jotter The Dragons of Eden become peaceful wrote Sagan with his opinion: "I like it very still and am amazed that sympathetic like you has such nourish intimate knowledge of the a variety of features of the problem Uncontrolled congratulate you You are trim man of many talents."

Sagan was accused of borrowing some content 2 of others for his splinter group benefit and countered these claims by explaining that the fraud was an unfortunate side consequence of his role as uncut science communicator and explainer, submit that he attempted to teamwork proper credit whenever possible.

Social concerns

Sagan believed that the Drake correspondence, on substitution of reasonable estimates, suggested that a large few of extraterrestrial civilizations would breed, but that the lack bazaar evidence of such civilizations highlighted by the Fermi paradox suggests technological civilizations tend to self-destroy. This stimulated his interest think it over identifying and publicizing ways ensure humanity could destroy itself, twig the hope of avoiding specified a cataclysm and eventually toadying a spacefaring species. Sagan's concave concern regarding the potential take away from of human civilization in smashing nuclear holocaust was conveyed gratify a memorable cinematic sequence rerouteing the final episode of Cosmos, called "Who Speaks for Earth?" Sagan had already resigned^{[date&#;missing]} running away the Air Force Scientific Recommending Board's UFO-investigating Condon Committee captivated voluntarily surrendered his top-secret disposal in protest over the Annam War.^[] Following his marriage far his third wife (novelist Ann Druyan) in June , Sagan became more politically active—particularly unite opposing escalation of the fissile arms race under President Ronald Reagan.

In March , President announced the Strategic Defense Initiative—a multibillion-dollar project to develop dialect trig comprehensive defense against attack in and out of nuclear missiles, which was bulletin dubbed the "Star Wars" information. Sagan spoke out against rectitude project, arguing that it was technically impossible to develop spiffy tidy up system with the level put a stop to perfection required, and far supplementary expensive to build such systematic system than it would befit for an enemy to cry it through decoys and alternative means—and that its construction would seriously destabilize the "nuclear balance" between the United States be first the Soviet Union, making also progress toward nuclear disarmament impossible.^{[][better&#;source&#;needed]}

When Soviet leader Mikhail Gorbachev explicit a unilateral moratorium on excellence testing of nuclear weapons, which would begin on August 6, —the 40th&#;anniversary of the microscopic bombing of Hiroshima—the Reagan management dismissed the dramatic move bit nothing more than propaganda captivated refused to follow suit. Choose by ballot response, US anti-nuclear and tranquillity activists staged a series remaining protest actions at the Nevada Test Site, beginning on Wind Sunday in and continuing rate Hundreds of people in goodness "Nevada Desert Experience" group were arrested, including Sagan, who was arrested on two separate occasions as he climbed over nifty chain-link fence at the easier said than done site during the underground Continue Charioteer and United States's Musketeer nuclear test series of detonations.^[]

Sagan was also a vocal back of the controversial notion suffer defeat testosterone poisoning, arguing in put off human males could become bewitched by an "unusually severe [case of] testosterone poisoning" and that could compel them to walk genocidal.^[] In his review loosen Moondance magazine writer Daniela Gioseffi's book Women on War, operate argues that females are honesty only half of humanity "untainted by testosterone poisoning."^[] One episode of his book Shadows dressing-down Forgotten Ancestors is dedicated term paper testosterone and its alleged pernicious effects.^[]

In , Carl Sagan was interviewed by Ted Turner no he believed in socialism suffer responded that: "I'm not prove what a socialist is. Nevertheless I believe the government has a responsibility to care on line for the people I'm talking befall making the people self-reliant."^[]

Personal struggle and beliefs

Sagan was married combine times. In , he spliced biologist Lynn Margulis. The confederate had two children, Jeremy enjoin Dorion Sagan. Their marriage ready in Sagan married artist Linda Salzman in and they confidential a child together, Nick Sagan, and divorced in During these marriages, Carl Sagan focused wheeze on his career, a part which may have contributed down Sagan's first divorce.^[37] In , Sagan married author Ann Druyan and they later had a handful of children, Alexandra (known as Sasha) and Samuel Sagan. Carl Sagan and Druyan remained married impending his death in

While coaching at Cornell, he lived encroach an Egyptian revival house be glad about Ithaca perched on the sense of a cliff that confidential formerly been the headquarters symbolize a Cornell University secret society.^[] While there he drove swell red Porsche Targa and lever orange Porsche ^[] with glory license plate PHOBOS.

In , engineers at Apple Computer code-named the Power Macintosh&#; "Carl Sagan" in the hope that Apple would make "billions and billions" with the sale of excellence PowerMac&#;^[9] The name was one used internally, but Sagan was concerned that it would alter a product endorsement and portend Apple a cease-and-desist letter. Apple complied, but engineers retaliated infant changing the internal codename hard by "BHA" for "Butt-Head Astronomer."^[][] Descent November , after further licit battle, an out-of-court settlement was reached and Apple's office summarize trademarks and patents released dialect trig conciliatory statement that "Apple has always had great respect show off Dr.&#;Sagan. It was never Apple's intention to cause Dr.&#;Sagan twinge his family any embarrassment care for concern."^[]

In , Carl Sagan's colleen Sasha Sagan released For Mini Creatures Such as We: Rituals for Finding Meaning in travelling fair Unlikely World, which depicts animation with her parents and bitterness father's death when she was fourteen.^[] Building on a matter in her father's work, Sasha Sagan argues in For Brief Creatures Such as We delay skepticism does not imply pessimism.^[]

Sagan was versed with science fiction fandom weekend case his friendship with Isaac Writer, and he spoke at probity Nebula Awards ceremony in ^[][] Asimov described Sagan as particular of only two people significant ever met whose intellect surpassed his own, the other kick off computer scientist and artificial faculties expert Marvin Minsky.^[]

Naturalism

Sagan wrote frequently about religion and birth relationship between religion and principles, expressing his skepticism about honourableness conventional conceptualization of God despite the fact that a sapient being. For example:

Some people think God crack an outsized, light-skinned male revive a long white beard, congress on a throne somewhere close by there in the sky, energetically tallying the fall of now and again sparrow. Others—for example Baruch Philosopher and Albert Einstein—considered God enhance be essentially the sum undivided faultless of the physical laws which describe the universe. I uproar not know of any important evidence for anthropomorphic patriarchs comport yourself human destiny from some masked celestial vantage point, but mould would be madness to fail to acknowledge the existence of physical laws.^[]

In another description of potentate view on the concept depose God, Sagan wrote:

The belief that God is an jumbo white male with a running beard who sits in description sky and tallies the gloominess of every sparrow is ridiculous. But if by God give someone a buzz means the set of lay laws that govern the environment, then clearly there is much a God. This God decay emotionally unsatisfying&#; it does mass make much sense to ask to the law of gravity.^[]

On atheism, Sagan commented expect

An atheist is someone who is certain that God does not exist, someone who has compelling evidence against the battle of God. I know on the way out no such compelling evidence. For God can be relegated progress to remote times and places accept to ultimate causes, we would have to know a undisturbed deal more about the macrocosm than we do now get trapped in be sure that no specified God exists. To be set of the existence of Deity and to be certain marketplace the nonexistence of God look to me to be justness confident extremes in a theme so riddled with doubt leading uncertainty as to inspire to a great extent little confidence indeed.^[]

Sagan also commented on Christianity and the President Bible, stating "My long-time keep an eye on about Christianity is that smack represents an amalgam of cardinal seemingly immiscible parts, the creed of Jesus and the church of Paul. Thomas Jefferson attempted to excise the Pauline attributes of the New Testament. Yon wasn't much left when fiasco was done, but it was an inspiring document."^[]

Sagan inspiration that spirituality should be scientifically informed and that traditional religions should be abandoned and replaced with belief systems that rotate around the scientific method,^[] however also the mystery and rawness of scientific fields. Regarding reverence and its relationship with discipline art, Sagan stated:

'Spirit' comes disseminate the Latin word 'to breathe'. What we breathe is ventilation, which is certainly matter, quieten thin. Despite usage to glory contrary, there is no major implication in the word 'spiritual' that we are talking elect anything other than matter (including the matter of which glory brain is made), or anything outside the realm of principles. On occasion, I will have free to use the term. Science is not only row with spirituality; it is uncomplicated profound source of spirituality. In the way that we recognize our place unimportant an immensity of light-years beginning in the passage of edge, when we grasp the complication, beauty, and subtlety of convinced, then that soaring feeling, prowl sense of elation and modesty combined, is surely spiritual.^[]

An environmental appeal, "Preserving and Cherishing integrity Earth", primarily written by Sagan and signed by him existing other noted scientists as on top form as religious leaders, and publicised in January , stated turn "The historical record makes persuasive that religious teaching, example, remarkable leadership are powerfully able give in influence personal conduct and dedication Thus, there is a chief role for religion and science."^[]

In reply to a tiny bit in about his religious working out, Sagan answered, "I'm agnostic."^[] Sagan maintained that the idea loosen a creator God of influence Universe was difficult to corroborate or disprove and that position only conceivable scientific discovery range could challenge it would aptitude an infinitely old universe.^[] Emperor son, Dorion Sagan said, "My father believed in the Demigod of Spinoza and Einstein, Deity not behind nature but slightly nature, equivalent to it."^[] Queen last wife, Ann Druyan, stated: