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Carl Sagan
Born	November 9, 1934(1934-11-09) Brooklyn, New York
Died	December 20, 1996 (aged 62) Seattle, Washington, U.S.
Residence	United States[1]
Nationality	American
Fields	Astronomy and planetary science
Institutions	Cornell University Harvard University
Alma mater	University of Chicago
Known for	Search for Extra-Terrestrial Intelligence (SETI) Cosmos: A Personal Voyage Cosmos Voyager Golden Record Pioneer plaque Contact Pale Blue Dot
Notable awards	Oersted Medal (1990) NASA Distinguished Public Service Medal (twice) Pulitzer Prize for General Non-Fiction (1978) National Academy of Sciences Public Welfare Medal (1994)

Carl Edward Sagan (November 9, 1934 – December 20, 1996) was an American astronomer, astrophysicist, author, and highly successful popularizer of astronomy, astrophysics and other natural sciences. He pioneered exobiology and promoted the Search for Extra-Terrestrial Intelligence (SETI).

He is world-famous for writing popular science books and for co-writing and presenting the award-winning 1980 television series Cosmos: A Personal Voyage, which has been seen by more than 500 million people in over 60 countries.^[2] A book to accompany the program was also published. He also wrote the novel Contact, the basis for the 1997 film of the same name. During his lifetime, Sagan published more than 600 scientific papers and popular articles and was author, co-author, or editor of more than 20 books. In his works, he was known for frequently advocating skeptical inquiry, secular humanism, and the scientific method.

Education and scientific career

Carl Sagan was born in Brooklyn, New York,^[3] to a Russian Jewish family. His father, Sam Sagan, was a Russian immigrant garment worker; his mother, Rachel Molly Gruber, a housewife. Carl was named in honor of Rachel's biological mother, Chaiya Clara, "the mother she never knew", in Sagan's words. Sagan graduated from Rahway High School in Rahway, New Jersey in 1951.^[4] He attended the University of Chicago, where he participated in the Ryerson Astronomical Society,^[5] received an A.B. with general and special honors (1954), an S.B. (1955) and an S.M. (1956) in physics, before earning a Ph.D. degree (1960) in astronomy and astrophysics.^[6] During his time as an undergraduate, Sagan spent some time working in the laboratory of the geneticist H. J. Muller. From 1960 to 1962 he was a Miller Fellow at the University of California, Berkeley. From 1962 to 1968, Sagan worked at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts.

Sagan lectured and did research annually at Harvard University until 1968, when he moved to Cornell University in New York. He became a full Professor at Cornell in 1971, and he directed the Laboratory for Planetary Studies there. From 1972 to 1981, Sagan was the Associate Director of the Center for Radio Physics and Space Research at Cornell.

Sagan was associated with the American space program from its inception. From the 1950s onward, he worked as an advisor to NASA, where one of his many duties included briefing the Apollo astronauts before their flights to the Moon. Sagan contributed to many of the robotic spacecraft missions that explored the solar system during his lifetime, arranging experiments on many of the expeditions. He conceived the idea of adding an unalterable and universal message on spacecraft destined to leave the solar system that could potentially be understood by any extraterrestrial intelligence that might find it. Sagan assembled the first physical message that was sent into space: a gold-anodized plaque, attached to the space probe Pioneer 10, launched in 1972. Pioneer 11, also carrying another copy of the plaque, was launched the following year. He continued to refine his designs; the most elaborate message he helped to develop and assemble was the Voyager Golden Record that was sent out with the Voyager space probes in 1977. Sagan often challenged the decisions to fund the Space Shuttle and Space Station at the expense of further robotic missions.^[7]

Sagan taught a course on critical thinking at Cornell University until he died in 1996 from pneumonia a few weeks after finding that he was in remission of a rare bone marrow disease.

Scientific achievements

Sagan's contributions were central to the discovery of the high surface temperatures of the planet Venus. In the early 1960s no one knew for certain the basic conditions of that planet's surface, and Sagan listed the possibilities in a report later depicted for popularization in a Time-Life book, Planets. His own view was that Venus was dry and very hot as opposed to the balmy paradise others had imagined. He had investigated radio emissions from Venus and concluded that there was a surface temperature of 500 °C (900 °F). As a visiting scientist to NASA's Jet Propulsion Laboratory, he contributed to the first Mariner missions to Venus, working on the design and management of the project. Mariner 2 confirmed his conclusions on the surface conditions of Venus in 1962.

Sagan was among the first to hypothesize that Saturn's moon Titan might possess oceans of liquid compounds on its surface and that Jupiter's moon Europa might possess subsurface oceans of water. This would make Europa potentially habitable for life.^[8] Europa's subsurface ocean of water was later indirectly confirmed by the spacecraft Galileo. Sagan also helped solve the mystery of the reddish haze seen on Titan, revealing that it is composed of complex organic molecules constantly raining down onto the moon's surface.

He further contributed insights regarding the atmospheres of Venus and Jupiter as well as seasonal changes on Mars. Sagan established that the atmosphere of Venus is extremely hot and dense with pressures increasing steadily all the way down to the surface. He also perceived global warming as a growing, man-made danger and likened it to the natural development of Venus into a hot, life-hostile planet through a kind of runaway greenhouse effect. Sagan and his Cornell colleague Edwin Ernest Salpeter speculated about life in Jupiter's clouds, given the planet's dense atmospheric composition rich in organic molecules. He studied the observed color variations on Mars’ surface and concluded that they were not seasonal or vegetational changes as most believed but shifts in surface dust caused by windstorms.

Sagan is best known, however, for his research on the possibilities of extraterrestrial life, including experimental demonstration of the production of amino acids from basic chemicals by radiation.^[9]

He is also the 1994 recipient of the Public Welfare Medal, the highest award of the National Academy of Sciences for "distinguished contributions in the application of science to the public welfare."^[10]

Scientific advocacy

Planetary Society members at the organization's founding. Carl Sagan is seated on the right.

Sagan's ability to convey his ideas allowed many people to better understand the cosmos—simultaneously emphasizing the value and worthiness of the human race, and the relative insignificance of the earth in comparison to the universe. He delivered the 1977 series of Royal Institution Christmas Lectures at the Royal Institution in London. He hosted and, with Ann Druyan, co-wrote and co-produced the highly popular thirteen-part PBS television series Cosmos: A Personal Voyage modeled on Jacob Bronowski's The Ascent of Man.

Sagan was a proponent of the search for extraterrestrial life. He urged the scientific community to listen with radio telescopes for signals from intelligent extraterrestrial life-forms. So persuasive was he that by 1982 he was able to get a petition advocating SETI published in the journal Science and signed by 70 scientists including seven Nobel Prize winners. This was a tremendous turnaround in the respectability of this controversial field. Sagan also helped Dr. Frank Drake write the Arecibo message, a radio message beamed into space from the Arecibo radio telescope on November 16, 1974, aimed at informing extraterrestrials about Earth.

Sagan was chief technology officer of the professional planetary research journal Icarus for twelve years. He co-founded the Planetary Society, the largest space-interest group in the world, with over 100,000 members in more than 149 countries, and was a member of the SETI Institute Board of Trustees. Sagan served as Chairman of the Division for Planetary Science of the American Astronomical Society, as President of the Planetology Section of the American Geophysical Union, and as Chairman of the Astronomy Section of the American Association for the Advancement of Science.

At the height of the Cold War, Sagan became involved in public awareness efforts for the effects of nuclear war when a mathematical climate model suggested that a substantial nuclear exchange could upset the delicate balance of life on Earth. He was one of five authors—the "S" of the "TTAPS" report as the research paper came to be known. He eventually co-authored the scientific paper hypothesizing a global nuclear winter following nuclear war.^[11] He also co-authored the book A Path Where No Man Thought: Nuclear Winter and the End of the Arms Race, a comprehensive examination of the phenomenon of nuclear winter.

Cosmos covered a wide range of scientific subjects including the origin of life and a perspective of our place in the universe. The series was first broadcast by the Public Broadcasting Service in 1980, winning an Emmy and a Peabody Award. It has been broadcast in more than 60 countries and seen by over 500 million people,^[2][12] making it the most widely watched PBS program in history.^[13]

Sagan also wrote books to popularize science, such as Cosmos, which reflected and expanded upon some of the themes of A Personal Voyage, and became the best-selling science book ever published in English;^[14] The Dragons of Eden: Speculations on the Evolution of Human Intelligence, which won a Pulitzer Prize; and Broca's Brain: Reflections on the Romance of Science. Sagan also wrote the best-selling science fiction novel Contact, but did not live to see the book's 1997 motion picture adaptation, which starred Jodie Foster and won the 1998 Hugo Award.

Pale Blue Dot: Earth is a bright pixel when photographed from "Voyager 1" six billion kilometres out (past Pluto). Sagan encouraged NASA to generate this image.

He wrote a sequel to Cosmos, Pale Blue Dot: A Vision of the Human Future in Space, which was selected as a notable book of 1995 by The New York Times. He appeared on PBS' Charlie Rose program in January 1995.^[15] Sagan also wrote an introduction for the bestselling book by Stephen Hawking, A Brief History of Time. Sagan was also known for his popularization of science, his efforts to increase scientific understanding among the general public, and his positions in favor of scientific skepticism and against pseudoscience, such as his debunking of the Betty and Barney Hill abduction. To mark the tenth anniversary of Sagan's passing, David Morrison, a former student of Sagan, recalled "Sagan's immense contributions to planetary research, the public understanding of science, and the skeptical movement" in Skeptical Inquirer.^[16]

Sagan hypothesized in January 1991 that enough smoke from the 1991 Kuwaiti oil fires "might get so high as to disrupt agriculture in much of South Asia…" He later conceded in The Demon-Haunted World that this prediction did not turn out to be correct: "it was pitch black at noon and temperatures dropped 4°–6°C over the Persian Gulf, but not much smoke reached stratospheric altitudes and Asia was spared."^[17] A 2007 study noted that modern computer models have been applied to the Kuwait oil fires, finding that individual smoke plumes are not able to loft smoke into the stratosphere, but that smoke from fires covering a large area, like some forest fires or the burning of cities that would be expected to follow a nuclear strike, would loft significant amounts of smoke into the stratosphere.^{[18][19][20][21]}

In his later years Sagan advocated the creation of an organized search for near Earth objects that might impact the Earth.^[22] When others suggested creating large nuclear bombs that could be used to alter the orbit of a NEO that was predicted to hit the Earth, Sagan proposed the Deflection Dilemma: If we create the ability to deflect an asteroid away from the Earth, then we also create the ability to deflect an asteroid towards the Earth—providing an evil power with a true doomsday bomb.^[23][24]

Billions and billions

Sagan with a model of the Viking Lander probes which would land on Mars. Sagan examined possible landing sites for Viking along with Mike Carr and Hal Masursky.

From Cosmos and his frequent appearances on The Tonight Show, Sagan became associated with the catch phrase "billions and billions". Sagan stated that he never actually used the phrase in the Cosmos series.^[25] The closest that he ever came was in the book Cosmos, where he talked of "billions upon billions":^[26]

A galaxy is composed of gas and dust and stars—billions upon billions of stars.

—Carl Sagan, Cosmos, chapter 1, page 3^[27]

However, his frequent use of the word billions, and distinctive delivery emphasizing the "b" (which he did intentionally, in place of more cumbersome alternatives such as "billions with a 'b'", in order to distinguish the word from "millions" in viewers' minds^[25]), made him a favorite target of comic performers including Johnny Carson, Gary Kroeger, Mike Myers,^[28] Bronson Pinchot, Penn Jillette, Harry Shearer, and others. Frank Zappa satirized the line in the song Be In My Video, noting as well 'atomic light.' Sagan took this all in good humor, and his final book was entitled Billions and Billions which opened with a tongue-in-cheek discussion of this catch phrase, observing that Carson himself was an amateur astronomer and that Carson's comic caricature often included real science.^[25]

The popular perception of his characterization of large cosmic quantities continued to be a sense of wonderment at the vastness of space and time, as in his phrase "The total number of stars in the Universe is larger than all the grains of sand on all the beaches of the planet Earth". However, this famous saying was widely misunderstood, as he was in fact referring to the world being at a "critical branch point in history" as in the following quote from Cosmos: A Personal Voyage, Episode 8: "Journeys in Space and Time":

Those worlds in space are as countless as all the grains of sand on all the beaches of the earth. Each of those worlds is as real as ours and every one of them is a succession of incidents, events, occurrences which influence its future. Countless worlds, numberless moments, an immensity of space and time. And our small planet at this moment, here we face a critical branch point in history: what we do with our world, right now, will propagate down through the centuries and powerfully affect the destiny of our descendants. It is well within our power to destroy our civilization and perhaps our species as well.

Sagan units

As a humorous tribute to him, a Sagan has been defined as a humorous unit of measurement equal to at least four billion, since the lower bound of a number conforming to the constraint of billions and billions must be two billion plus two billion.^[29][30] Assuming one uses the short scale definition for billion, there are nearly 100 Sagan (400,000,000,000) stars in the Milky Way galaxy.

Apple Computer

In 1994, Apple Computer began developing the Power Macintosh 7100. They code-named some computers after astronomers, such as Copernicus, and for the 7100 chose the internal code name "Carl Sagan", a possible inference being that the mid-range PowerMac 7100 should make Apple "billions and billions."^[3]

Though the internal project name was never used in public marketing, it did come up in Usenet postings and news of the name grew from there. When Sagan learned of this he sued Apple Computer to force the use of a different project name. Other models released conjointly had code names such as "Cold fusion" and "Piltdown Man", and Sagan was displeased at being associated with what he considered pseudoscience. (He was at the time writing a book discrediting pseudoscience.)^[31]

Though Sagan lost the lawsuit Apple engineers complied with his demands anyway and renamed the project "BHA" (for Butt-Head Astronomer). Sagan promptly sued Apple for libel over the new name, claiming that it subjected him to contempt and ridicule, but he lost this lawsuit as well. Still, the 7100 saw another name change: it was finally referred to internally as "LAW" (Lawyers Are Wimps).^[32][33]

Social concerns

Sagan believed that the Drake equation, on substitution of reasonable estimates, suggested that a large number of extraterrestrial civilizations would form, but that the lack of evidence of such civilizations highlighted by the Fermi paradox suggests technological civilizations tend to destroy themselves rather quickly. This stimulated his interest in identifying and publicizing ways that humanity could destroy itself, with the hope of avoiding such a cataclysm and eventually becoming a spacefaring species. Sagan's deep concern regarding the potential destruction of human civilization in a nuclear holocaust was conveyed in a memorable cinematic sequence in the final episode of Cosmos, called "Who Speaks for Earth?" Sagan had already resigned from the Air Force Scientific Advisory Board and voluntarily surrendered his top-security clearance in protest over the Vietnam War.^[34] Following his marriage to his third wife (novelist Ann Druyan) in June 1981, Sagan became more politically active—particularly in opposing escalation of the nuclear arms race under President Ronald Reagan.

In March 1983, Reagan announced the Strategic Defense Initiative—a multi-billion dollar project to develop a comprehensive defense against attack by nuclear missiles, which was quickly dubbed the "Star Wars" program. Sagan spoke out against the project, arguing that it was technically impossible to develop a system with the level of perfection required, and far more expensive to build than for an enemy to defeat through decoys and other means—and that its construction would seriously destabilize the nuclear balance between the United States and the Soviet Union, making further progress toward nuclear disarmament impossible.

When Soviet leader Mikhail Gorbachev declared a unilateral moratorium on the testing of nuclear weapons, which would begin on August 6, 1985—the 40th anniversary of the atomic bombing of Hiroshima—the Reagan administration dismissed the dramatic move as nothing more than propaganda, and refused to follow suit. In response, American anti-nuclear and peace activists staged a series of protest actions at the Nevada Test Site, beginning on Easter Sunday in 1986 and continuing through 1987. Hundreds of people were arrested, including Sagan, who was arrested on two separate occasions as he climbed over a chain-link fence at the test site.

Personal life and beliefs

Sagan married three times: in 1957, to biologist Lynn Margulis, mother of Dorion Sagan and Jeremy Sagan; in 1968, to artist Linda Salzman, mother of Nick Sagan; and in 1981, to author Ann Druyan, mother of Alexandra Rachel (Sasha) Sagan and Samuel Democritus Sagan. His marriage to Druyan continued until his death in 1996.

Isaac Asimov described Sagan as one of only two people he ever met whose intellect surpassed his own. The other, he claimed, was the computer scientist and artificial intelligence expert Marvin Minsky.^[35]

Sagan wrote frequently about religion and the relationship between religion and science, expressing his skepticism about the conventional conceptualization of God as a sapient being. For example:

Some people think God is an outsized, light-skinned male with a long white beard, sitting on a throne somewhere up there in the sky, busily tallying the fall of every sparrow. Others—for example Baruch Spinoza and Albert Einstein—considered God to be essentially the sum total of the physical laws which describe the universe. I do not know of any compelling evidence for anthropomorphic patriarchs controlling human destiny from some hidden celestial vantage point, but it would be madness to deny the existence of physical laws.^[36]

Sagan, however, denied that he was an atheist: "An atheist has to know a lot more than I know."^[37] In reply to a question in 1996 about his religious beliefs, Sagan answered, "I'm agnostic."^[38] Sagan maintained that the idea of a creator of the universe was difficult to prove or disprove and that the only conceivable scientific discovery that could challenge it would be an infinitely old universe.^[39]

In 2006, Ann Druyan edited Sagan's 1985 Glasgow Gifford Lectures in Natural Theology into a book, The Varieties of Scientific Experience: A Personal View of the Search for God, in which he elaborates on his views of divinity in the natural world.

Sagan is also widely regarded as a freethinker or skeptic; one of his most famous quotations, in Cosmos, was, "Extraordinary claims require extraordinary evidence."^[40] This was based on a nearly identical statement by fellow founder of the Committee for the Scientific Investigation of Claims of the Paranormal founder Marcello Truzzi, "Extraordinary claims require extraordinary proof."^[41] This idea originated with Pierre-Simon Laplace (1749-1827), a French mathematician and astronomer who said, "The weight of evidence for an extraordinary claim must be proportioned to its strangeness."^[42] Sagan nominated three areas within paranormal research that he considered to have sufficient experimental support, albeit dubious, to warrant serious study. These related to thoughts barely affecting random number generators (psychokinesis); projection of images from one person to another (telepathy); and young children sometimes reporting verifiable details of previous lives (reincarnation research). He was at pains to point out that he was not convinced by the validity of these contentions, merely that they might be true.^[43]

Late in his life, Sagan's books elaborated on his skeptical, naturalistic view of the world. In The Demon-Haunted World: Science as a Candle in the Dark, he presented tools for testing arguments and detecting fallacious or fraudulent ones, essentially advocating wide use of critical thinking and the scientific method. The compilation Billions and Billions: Thoughts on Life and Death at the Brink of the Millennium, published in 1997 after Sagan's death, contains essays written by Sagan, such as his views on abortion, and his widow Ann Druyan's account of his death as a skeptic, agnostic, and freethinker.

Sagan warned against humans' tendency to anthropocentrism. He was the faculty adviser for the Cornell Students for the Ethical Treatment of Animals. In the Cosmos chapter "Blues For a Red Planet", Sagan wrote, "If there is life on Mars, I believe we should do nothing with Mars. Mars then belongs to the Martians, even if the Martians are only microbes."^[44]

Sagan was a user of marijuana. Under the pseudonym "Mr. X", he contributed an essay about smoking cannabis to the 1971 book Marihuana Reconsidered.^[45][46] The essay explained that marijuana use had helped to inspire some of Sagan's works and enhance sensual and intellectual experiences. After Sagan's death, his friend Lester Grinspoon disclosed this information to Sagan's biographer, Keay Davidson. The publishing of the biography, Carl Sagan: A Life, in 1999 brought media to this aspect of Sagan's life.^[47][48][49]

In 1966, Sagan was asked to contribute an interview about the possibility of extraterrestrials to a proposed introduction to the film 2001: A Space Odyssey. Sagan reportedly asked for control and a percentage of the film's box office receipts in return; these terms were rejected.^[50]

Sagan and UFOs

Sagan had some interest in UFO reports from at least 1964 when he had several conversations on the subject with Jacques Vallee.^[51] Though quite skeptical of any extraordinary answer to the UFO question, Sagan thought scientists should study the phenomenon, at least because there was widespread public interest in UFO reports.

Stuart Appelle notes that Sagan "wrote frequently on what he perceived as the logical and empirical fallacies regarding UFOs and the abduction experience. Sagan rejected an extraterrestrial explanation for the phenomenon but felt there were both empirical and pedagogical benefits for examining UFO reports and that the subject was, therefore, a legitimate topic of study."^[52]

In 1966, Sagan was a member of the Ad Hoc Committee to Review Project Blue Book, the U.S. Air Force's UFO investigation project. The committee concluded Blue Book had been lacking as a scientific study, and recommended a university-based project to give the UFO phenomenon closer scientific scrutiny. The result was the Condon Committee (1966–1968), led by physicist Edward Condon, and in their final report they formally concluded that UFOs, regardless of what any of them actually were, did not behave in a manner consistent with a threat to national security.

Ron Westrum writes that "The high point of Sagan's treatment of the UFO question was the AAAS's symposium in 1969. A wide range of educated opinions on the subject were offered by participants, including not only proponents such as James McDonald and J. Allen Hynek but also skeptics like astronomers William Hartmann and Donald Menzel. The roster of speakers was balanced, and it is to Sagan's credit that this event was presented in spite of pressure from Edward Condon".^[51] With physicist Thornton Page, Sagan edited the lectures and discussions given at the symposium; these were published in 1972 as UFOs: A Scientific Debate. Some of Sagan's many books examine UFOs (as did one episode of Cosmos) and he claimed a religious undercurrent to the phenomenon.

Sagan again revealed his views on interstellar travel in his 1980 Cosmos series. In one of his last written works, Sagan argued that the chances of extraterrestrial spacecraft visiting Earth are vanishingly small. However, Sagan did think it plausible that Cold War concerns contributed to governments misleading their citizens about UFOs, and that "some UFO reports and analyses, and perhaps voluminous files, have been made inaccessible to the public which pays the bills ... It's time for the files to be declassified and made generally available." He cautioned against jumping to conclusions about suppressed UFO data and stressed that there was no strong evidence that aliens were visiting the Earth either in the past or present.^[53]

Death

Stone dedicated to Carl Sagan in the Celebrity Path of the Brooklyn Botanic Garden

After a long and difficult fight with myelodysplasia, which included three bone marrow transplants, Sagan died of pneumonia at the age of 62 at the Fred Hutchinson Cancer Research Center in Seattle, Washington, on December 20, 1996. After landing, the unmanned Mars Pathfinder spacecraft was renamed the Carl Sagan Memorial Station on July 5, 1997. Asteroid 2709 Sagan is also named in his honor. He was buried at Lakeview Cemetery in Ithaca, New York.

Trivia

The 1997 movie Contact, based on Sagan's novel of the same name and finished after his death, ends with the dedication "For Carl".

On November 9, 2001, on what would have been Sagan's 67th birthday, the NASA Ames Research Center dedicated the site for the Carl Sagan Center for the Study of Life in the Cosmos. "Carl was an incredible visionary, and now his legacy can be preserved and advanced by a 21st century research and education laboratory committed to enhancing our understanding of life in the universe and furthering the cause of space exploration for all time", said NASA Administrator Daniel Goldin. Ann Druyan was at the Center as it opened its doors on October 22, 2006.

Sagan's son, Nick Sagan, wrote several episodes in the Star Trek franchise. In an episode of Star Trek: Enterprise entitled "Terra Prime", a quick shot is shown of the relic rover Sojourner, part of the Mars Pathfinder mission, placed by a historical marker at Carl Sagan Memorial Station on the Martian surface. The marker displays a quote from Sagan: "Whatever the reason you're on Mars, I'm glad you're there, and I wish I was with you." Sagan's student Steve Squyres led the team that landed the Spirit Rover and Opportunity Rover successfully on Mars in 2004.

Sagan has at least three awards named in his honor:

• The Carl Sagan Memorial Award presented jointly since 1997 by the American Astronautical Society (AAS) and the Planetary Society,
• The Carl Sagan Medal for Excellence in Public Communication in Planetary Science presented since 1998 by the American Astronomical Society's Division for Planetary Sciences (AAS/DPS) for outstanding communication by an active planetary scientist to the general public — Carl Sagan was one of the original organizing committee members of the DPS, and
• The Carl Sagan Award for Public Understanding of Science presented by the Council of Scientific Society Presidents (CSSP) — Sagan himself was the first recipient of the CSSP award in 1993.^[54]

In 2006, the Carl Sagan Medal was awarded to astrobiologist and author David Grinspoon, the son of Sagan's friend Lester Grinspoon.

On December 20, 2006, the tenth anniversary of Sagan's death, a blogger, Joel Schlosberg, organized a Carl Sagan "blog-a-thon" to commemorate Sagan's death, and the idea was supported by Nick Sagan.^[55] Many members of the blogging community participated.

In 2008, Benn Jordan, also known as The Flashbulb, released the album "Pale Blue Dot: A Tribute to Carl Sagan".

In 2009, clips from Carl Sagan's Cosmos were used as the basis for A Glorious Dawn, the first video produced for the Symphony of Science, an educational music video production by composer John Boswell. Musician Jack White later released this song as a vinyl single under his record label Third Man Records.^[56] Additional clips were used in several followup videos which featured Sagan alongside other noted scientists and proponents of rational thinking, such as Richard Dawkins, Richard Feynman, Lawrence M. Krauss, Bill Nye, and Neil deGrasse Tyson. So far, Sagan is the only scientist featured in every Symphony of Science video.

Also in 2009, the 75th anniversary of Carl Sagan's birth, the First "Carl Sagan Day" has been celebrated on November 7.^[57]

Awards and honors

NASA Distinguished Public Service Medal

• Annual Award for Television Excellence - 1981 - Ohio State University - PBS series Cosmos
• Apollo Achievement Award - National Aeronautics and Space Administration
• NASA Distinguished Public Service Medal - National Aeronautics and Space Administration (twice)
• Emmy - Outstanding Individual Achievement - 1981 - PBS series Cosmos
• Emmy - Outstanding Informational Series - 1981 - PBS series Cosmos
• Exceptional Scientific Achievement Medal - National Aeronautics and Space Administration
• Helen Caldicott Leadership Award - Women's Action for Nuclear Disarmament
• Hugo Award - 1981 - Cosmos
• Humanist of the Year - 1981 - Awarded by the American Humanist Association
• In Praise of Reason Award - 1987 - Committee for the Scientific Investigation of Claims of the Paranormal
• Isaac Asimov Award - 1994 - Committee for the Scientific Investigation of Claims of the Paranormal
• John F. Kennedy Astronautics Award - American Astronautical Society
• John W. Campbell Memorial Award - 1974 - Cosmic Connection: An Extraterrestrial Perspective
• Joseph Priestley Award - "For distinguished contributions to the welfare of mankind"
• Klumpke-Roberts Award of the Astronomical Society of the Pacific - 1974
• Konstantin Tsiolkovsky Medal - Awarded by the Soviet Cosmonauts Federation
• Locus Award 1986 - Contact
• Lowell Thomas Award - Explorers Club - 75th Anniversary
• Masursky Award - American Astronomical Society
• Miller Research Fellowship - Miller Institute (1960–1962)
• New Jersey Hall of Fame - 2009 inductee ^[58]
• Oersted Medal - 1990 - American Association of Physics Teachers
• Peabody Award - 1980 - PBS series Cosmos
• Prix Galbert - The international prize of Astronautics
• Public Welfare Medal - 1994 - National Academy of Sciences
• Pulitzer Prize for General Non-Fiction - 1978 - The Dragons of Eden
• SF Chronicle Award - 1998 - Contact
• Named the "99th Greatest American" on the June 5, 2005, Greatest American show on the Discovery Channel

Publications

• Planets (LIFE Science Library), Sagan, Carl, Jonathon Norton Leonard and editors of Life, Time, Inc., 1966
• Intelligent Life in the Universe, I.S. Shklovskii coauthor, Random House, 1966, 509 pgs
• UFO's: A Scientific Debate, Thornton Page coauthor, Cornell University Press, 1972, 310 pgs
• Communication with Extraterrestrial Intelligence. MIT Press, 1973, 428 pgs
• Mars and the Mind of Man, Sagan, Carl, et al., Harper & Row, 1973, 143 pgs
• Cosmic Connection: An Extraterrestrial Perspective, Jerome Agel coauthor, Anchor Press, 1973, ISBN 0-521-78303-8, 301 pgs
• Other Worlds. Bantam Books, 1975
• Murmurs of Earth: The Voyager Interstellar Record, Sagan, Carl, et al., Random House, ISBN 0-394-41047-5, 1978
• The Dragons of Eden: Speculations on the Evolution of Human Intelligence. Ballantine Books, 1978, ISBN 0-345-34629-7, 288 pgs
• Broca's Brain: Reflections on the Romance of Science. Ballantine Books, 1979, ISBN 0-345-33689-5, 416 pgs
• Cosmos. Random house, 1980. Random House New Edition, May 7, 2002, ISBN 0-375-50832-5, 384 pgs
• The Cold and the Dark: The World after Nuclear War, Sagan, Carl et al., Sidgwick & Jackson, 1985
• Comet, Ann Druyan coauthor, Ballantine Books, 1985, ISBN 0-345-41222-2, 496 pgs
• Contact. Simon and Schuster, 1985; Reissued August 1997 by Doubleday Books, ISBN 1-56865-424-3, 352 pgs
• A Path Where No Man Thought: Nuclear Winter and the End of the Arms Race, Richard Turco coauthor, Random House, 1990, ISBN 0-394-58307-8, 499 pgs
• Shadows of Forgotten Ancestors: A Search for Who We Are, Ann Druyan coauthor, Ballantine Books, October 1993, ISBN 0-345-38472-5, 528 pgs
• Pale Blue Dot: A Vision of the Human Future in Space. Random House, November 1994, ISBN 0-679-43841-6, 429 pgs
• The Demon-Haunted World: Science as a Candle in the Dark. Ballantine Books, March 1996, ISBN 0-345-40946-9, 480 pgs (note: the book was first published and copyrighted in 1995 with an errata slip inserted)
• Billions and Billions: Thoughts on Life and Death at the Brink of the Millennium, Ann Druyan coauthor, Ballantine Books, June 1997, ISBN 0-345-37918-7, 320 pgs
• The Varieties of Scientific Experience: A Personal View of the Search for God, Carl Sagan (writer) & Ann Druyan (editor), 1985 Gifford lectures, Penguin Press HC, November 2006, ISBN 1-59420-107-2, 304 pgs

References

Further reading

• Davidson, Keay (1999). Carl Sagan: A Life. New York: John Wiley & Sons. pp. 33–41. ISBN 0471252867. 
• Head, Tom (ed.) (2005). Conversations with Carl Sagan. Jackson, Mississippi: University Press of Mississippi. ISBN 1578067367. 
• Poundstone, William (1999). Carl Sagan: A Life in the Cosmos. New York: Henry Holt & Company. ISBN 0805057668. 
• Morrison, David (2006). "Carl Sagan: The People's Astronomer" (PDF). AmeriQuests 3 (2). http://ejournals.library.vanderbilt.edu/ameriquests/include/getdoc.php?id=402&article=93&mode=pdf. 
• Achenbach, Joel (1999). Captured by Aliens: the search for life and truth in a very large universe. New York: Simon & Schuster. ISBN 0-684-84856-2. [Includes detailed account of Sagan's role in the search for extraterrestrial life. Lay summary]. 

External links

• The Carl Sagan Portal
• Carl Sagan at the Internet Movie Database
• Works by or about Carl Sagan in libraries (WorldCat catalog)
• Carl Sagan at Find a Grave
• Carl Sagan Prize for Science Popularization
• Carl Sagan Medal for Excellence in Public Communication in Planetary Science, presented by the American Astronomical Society's Division for Planetary Sciences (AAS/DPS)

Carl Sagan Books Mars and the Mind of Man · The Dragons of Eden: Speculations on the Evolution of Human Intelligence · Broca's Brain: Reflections on the Romance of Science · Cosmos · The Nuclear Winter: The World After Nuclear War · Contact · Comet · A Path Where No Man Thought: Nuclear Winter and the End of the Arms Race · Shadows of Forgotten Ancestors: A Search for Who We Are · Pale Blue Dot: A Vision of the Human Future in Space · The Demon-Haunted World: Science as a Candle in the Dark · Billions and Billions: Thoughts on Life and Death at the Brink of the Millennium Media Cosmos: A Personal Voyage · Contact See also SETI · Pioneer plaque · Voyager Golden Record · Pale Blue Dot · Linda Salzman Sagan · Nick Sagan  · Ann Druyan

From Wikiquote

We make our world significant by the courage of our questions and by the depth of our answers.

Carl Edward Sagan (9 November 1934 – 20 December 1996) was an American astronomer and popular science writer.

Sourced

• It seems to me what is called for is an exquisite balance between two conflicting needs: the most skeptical scrutiny of all hypotheses that are served up to us and at the same time a great openness to new ideas … If you are only skeptical, then no new ideas make it through to you … On the other hand, if you are open to the point of gullibility and have not an ounce of skeptical sense in you, then you cannot distinguish the useful ideas from the worthless ones.
  • "The Burden of Skepticism" (1987)

• Humans — who enslave, castrate, experiment on, and fillet other animals — have had an understandable penchant for pretending animals do not feel pain. A sharp distinction between humans and 'animals' is essential if we are to bend them to our will, make them work for us, wear them, eat them — without any disquieting tinges of guilt or regret. It is unseemly of us, who often behave so unfeelingly toward other animals, to contend that only humans can suffer. The behavior of other animals renders such pretensions specious. They are just too much like us.
  • "Shadows of Forgotten Ancestors" (1992) (co-written with Dr. Ann Druyan)

The truth may be puzzling. It may take some work to grapple with. It may be counterintuitive. It may contradict deeply held prejudices. It may not be consonant with what we desperately want to be true. But our preferences do not determine what's true.

• The truth may be puzzling. It may take some work to grapple with. It may be counterintuitive. It may contradict deeply held prejudices. It may not be consonant with what we desperately want to be true. But our preferences do not determine what's true. We have a method, and that method helps us to reach not absolute truth, only asymptotic approaches to the truth — never there, just closer and closer, always finding vast new oceans of undiscovered possibilities. Cleverly designed experiments are the key.
  • "Wonder and Skepticism", Skeptical Enquirer Volume 19, Issue 1, (January-February 1995)

• We have designed our civilization based on science and technology and at the same time arranged things so that almost no one understands anything at all about science and technology. This is a clear prescription for disaster.
  • Interview with Anne Kalosh, 1995

• I would love to believe that when I die I will live again, that some thinking, feeling, remembering part of me will continue. But much as I want to believe that, and despite the ancient and worldwide cultural traditions that assert an afterlife, I know of nothing to suggest that it is more than wishful thinking.
  The world is so exquisite with so much love and moral depth, that there is no reason to deceive ourselves with pretty stories for which there's little good evidence. Far better it seems to me, in our vulnerability, is to look death in the eye and to be grateful every day for the brief but magnificent opportunity that life provides.
  • "In the Valley of the Shadow" PARADE magazine (10 March 1996)

If you wish to make an apple pie from scratch, you must first invent the universe.

• I try not to think with my gut. If I'm serious about understanding the world, thinking with anything besides my brain, as tempting as that might be, is likely to get me into trouble.

• ...that kind of skeptical questioning, don't accept what authority tells you -attitude of science- is also nearly identical to the attitude of mind necessary for a functioning democracy. Science and democracy have very consonant values and approaches, and I don't think you can have one without the other.
  • Talk of the Nation, 3 May 1996

• Who is more humble? The scientist who looks at the universe with an open mind and accepts whatever the universe has to teach us, or somebody who says everything in this book must be considered the literal truth and never mind the fallibility of all the human beings involved?
  • Interview with Charlie Rose, 1996

• In science it often happens that scientists say, "You know that's a really good argument; my position is mistaken," and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion.
  • Keynote address at CSICOP conference, 1987

Mr. X (1969)

• I am convinced that there are genuine and valid levels of perception available with cannabis (and probably with other drugs) which are, through the defects of our society and our educational system, un-available to us without such drugs.
  • published in Dr. Lester Grinspoon's Marihuana Reconsidered (1971)

• ...The illegality of cannabis is outrageous, an impediment to full utilization of a drug which helps produce the serenity and insight, sensitivity and fellowship so desperately needed in this increasingly mad and dangerous world.
  • published in Dr. Lester Grinspoon's Marihuana Reconsidered (1971)

• There is a myth about such highs: the user has an illusion of great insight, but it does not survive scrutiny in the morning. I am convinced that this is an error, and that the devastating insights achieved when high are real insights; the main problem is putting these insights in a form acceptable to the quite different self that we are when we're down the next day.
  • published in Dr. Lester Grinspoon's Marihuana Reconsidered (1971)

Cosmos (1980)

• In the vastness of space and the immensity of time, it is my joy to share a planet and an epoch with Annie.
  • Dedication

• The Cosmos is all that is or ever was or ever will be. Our feeblest contemplations of the Cosmos stir us — there is a tingling in the spine, a catch in the voice, a faint sensation of a distant memory, as if we were falling from a great height. We know we are approaching the greatest of mysteries.
  • Page 4

• The size and age of the Cosmos are beyond ordinary human understanding. Lost somewhere between immensity and eternity is our tiny planetary home. In a cosmic perspective, most human concerns seem insignificant, even petty. And yet our species is young and curious and brave and shows much promise. In the last few millennia we have made the most astonishing and unexpected discoveries about the Cosmos and our place within it, explorations that are exhilarating to consider. They remind us that humans have evolved to wonder, that understanding is a joy, that knowledge is prerequisite to survival. I believe our future depends on how well we know this Cosmos in which we float like a mote of dust in the morning sky.
  • Page 4

• Imagination will often carry us to worlds that never were. But without it we go nowhere.
  • Page 4

• We are like butterflies who flutter for a day and think it's forever.
  • Page 20 [1]

• For most of human history we have searched for our place in the cosmos. Who are we? What are we? We find that we inhabit an insignificant planet of a hum-drum star lost in a galaxy tucked away in some forgotten corner of a universe in which there are far more galaxies than people. This perspective is a courageous continuation of our penchant for constructing and testing mental models of the skies; the Sun as a red-hot stone, the stars as a celestial flame, the Galaxy as the backbone of night.
  • Page 193

• If we long for our planet to be important, there is something we can do about it. We make our world significant by the courage of our questions and by the depth of our answers.
  • Page 193

We are made of star stuff...

• We embarked on our cosmic voyage with a question first framed in the childhood of our species and in each generation asked anew with undiminished wonder: What are the stars? Exploration is in our nature. We began as wanderers, and we are wanderers still. We have lingered long enough on the shores of the cosmic ocean. We are ready at last to set sail for the stars.
  • Page 193

• If you wish to make an apple pie from scratch, you must first create the universe.
  • Page 218

• A googolplex is precisely as far from infinity as is the number 1... no matter what number you have in mind, infinity is larger.
  • Page 220

• We are made of star stuff. For the most part, atoms heavier than hydrogen were created in the interiors of stars and then expelled into space to be incorporated into later stars. The Sun is probably a third generation star.

• Books permit us to voyage through time, to tap the wisdom of our ancestors. The library connects us with the insights and knowledge, painfully extracted from Nature, of the greatest minds that ever were, with the best teachers, drawn from the entire planet and from all of our history, to instruct us without tiring, and to inspire us to make our own contribution to the collective knowledge of the human species. Public libraries depend on voluntary contributions. I think the health of our civilization, the depth of our awareness about the underpinnings of our culture and our concern for the future can all be tested by how well we support our libraries.
  • Page 282

As the ancient myth makers knew, we are children equally of the earth and the sky.

• The choice is with us still, but the civilization now in jeopardy is all humanity. As the ancient myth makers knew, we are children equally of the earth and the sky. In our tenure of this planet we've accumulated dangerous evolutionary baggage — propensities for aggression and ritual, submission to leaders, hostility to outsiders — all of which puts our survival in some doubt. But we've also acquired compassion for others, love for our children and desire to learn from history and experience, and a great soaring passionate intelligence — the clear tools for our continued survival and prosperity. Which aspects of our nature will prevail is uncertain, particularly when our visions and prospects are bound to one small part of the small planet Earth. But up there in the immensity of the Cosmos, an inescapable perspective awaits us. There are not yet any obvious signs of extraterrestrial intelligence and this makes us wonder whether civilizations like ours always rush implacably, headlong, toward self-destruction. National boundaries are not evident when we view the Earth from space. Fanatical ethnic or religious or national chauvinisms are a little difficult to maintain when we see our planet as a fragile blue crescent fading to become an inconspicuous point of light against the bastion and citadel of the stars. Travel is broadening."
  • Page 318

• We have heard the rationales offered by the nuclear superpowers. We know who speaks for the nations. But who speaks for the human species? Who speaks for Earth?
  • Page 329

• Those afraid of the universe as it really is, those who pretend to nonexistent knowledge and envision a Cosmos centered on human beings will prefer the fleeting comforts of superstition. They avoid rather than confront the world. But those with the courage to explore the weave and structure of the Cosmos, even where it differs profoundly from their wishes and prejudices, will penetrate its deepest mysteries.
  • Page 333

Human history can be viewed as a slowly dawning awareness that we are members of a larger group.

• Human history can be viewed as a slowly dawning awareness that we are members of a larger group. Initially our loyalties were to ourselves and our immediate family, next, to bands of wandering hunter-gatherers, then to tribes, small settlements, city-states, nations. We have broadened the circle of those we love. We have now organized what are modestly described as super-powers, which include groups of people from divergent ethnic and cultural backgrounds working in some sense together — surely a humanizing and character building experience. If we are to survive, our loyalties must be broadened further, to include the whole human community, the entire planet Earth. Many of those who run the nations will find this idea unpleasant. They will fear the loss of power. We will hear much about treason and disloyalty. Rich nation-states will have to share their wealth with poor ones. But the choice, as H. G. Wells once said in a different context, is clearly the universe or nothing.
  • Page 339

• Every one of us is precious in the cosmic perspective. If a human disagrees with you, let him live. In a hundred billion galaxies, you will not find another.
  • Page 339

• History is full of people who out of fear, or ignorance, or lust for power have destroyed knowledge of immeasurable value which truly belongs to us all. We must not let it happen again.

• We are star stuff which has taken its destiny into its own hands. The loom of time and space works the most astonishing transformations of matter.

• Extraordinary claims require extraordinary evidence.

• Observation: I can't see a thing. Conclusion: Dinosaurs.

• We are a way for the universe to know itself.
  • From the Cosmos documentary

Contact (1985)

Look, all I'm asking is for you to just have the tiniest bit of vision. You know, to just sit back for one minute and look at the big picture...

• Science fiction. You're right, it's crazy. In fact, it's even worse than that, it's nuts. You wanna hear something really nutty? I heard of a couple guys who wanna build something called an airplane, you know you get people to go in, and fly around like birds, it's ridiculous, right? And what about breaking the sound barrier, or rockets to the moon? Atomic energy, or a mission to Mars? Science fiction, right? Look, all I'm asking is for you to just have the tiniest bit of vision. You know, to just sit back for one minute and look at the big picture. To take a chance on something that just might end up being the most profoundly impactful moment for humanity, for the history… of history.

• In the fabric of space and in the nature of matter, as in a great work of art, there is, written small, the artist's signature.

• For small creatures such as we the vastness is bearable only through love.

• You can't convince a believer of anything; for their belief is not based on evidence, it's based on a deep seated need to believe.
  • Dr. Arroway

• A celibate clergy is an especially good idea, because it tends to suppress any hereditary propensity toward fanaticism.
  • Page 244

• "Let's see if I've got this straight," he returned. It was a phrase of hers that he had adopted "It's a lazy Saturday afternoon, and there's this couple lying naked in bed reading the Enclyclopaedia Britannica to each other, and arguing about whether the Andromeda Galaxy is more 'numinous' than the Resurrection. Do they know how to have a good time or don't they?"
  • Page 154

• The major religions on the Earth contradict each other left and right. You can't all be correct. And what if all of you are wrong? It's a possibility, you know. You must care about the truth, right? Well, the way to winnow through all the differing contentions is to be skeptical. I'm not any more skeptical about your religious beliefs than I am about every new scientific idea I hear about. But in my line of work, they're called hypotheses, not inspiration and not revelation.
  • Dr. Arroway, Page 162

• What I'm saying is, if God wanted to send us a message, and ancient writings were the only way he could think of doing it, he could have done a better job.
  • Dr. Arroway, Page 164

• Anything you don't understand, Mr. Rankin, you attribute to God. God for you is where you sweep away all the mysteries of the world, all the challenges to our intelligence. You simply turn your mind off and say God did it.
  • Dr. Arroway, Page 166

• You see, the religious people — most of them — really think this planet is an experiment. That's what their beliefs come down to. Some god or other is always fixing and poking, messing around with tradesmen's wives, giving tablets on mountains, commanding you to mutilate your children, telling people what words they can say and what words they can't say, making people feel guilty about enjoying themselves, and like that. Why can't the gods leave well enough alone? All this intervention speaks of incompetence. If God didn't want Lot's wife to look back, why didn't he make her obedient, so she'd do what her husband told her? Or if he hadn't made Lot such a shithead, maybe she would've listened to him more. If God is omnipotent and omniscient, why didn't he start the universe out in the first place so it would come out the way he wants? Why's he constantly repairing and complaining? No, there's one thing the Bible makes clear: The biblical God is a sloppy manufacturer. He's not good at design, he's not good at execution. He'd be out of business if there was any competition.
  • Sol Hadden, page 285

Cosmos: A Personal Voyage (1990 Update) is a thirteen-part television program television series

Episode 1: The Shores of the Cosmic Ocean

03 min 55 sec

05 min 20 sec

53 min 15 sec

56 min 20 sec

57 min 0 sec

Episode 3: The Harmony of the Worlds

55 min 0 sec

Episode 4: Heaven and Hell

33 min 20 sec

Episode 7: The Backbone of Night

0 min 40 sec

37 min 45 sec

38 min 10 sec

40 min 35 sec

Episode 8: Journeys in Space and Time

54 min 55 sec

Episode 11: The Persistence of Memory

42 min 33 sec

Episode 12: Encyclopedia Galactica

0 min 45 sec

1 min 10 sec

7 min 25 sec

(Back reference to UFO abduction claims)

55 min 40 sec

Text Quote

Extract of entry in fictional 'Encyclopaedia Galactica' for Earth

Episode 13: Who Speaks for Earth?

0 min 40 sec

Episode opening voiceover; quote from The Bible, Deuteronomy 30:19 , American Standard Version

4 min 40 sec

6 min 10 sec

17 min 40 sec

22 min 35 sec

25 Min 10 Sec

28 min 30 sec

36 min 20 sec

54 min 25 sec

55 min 20 sec

Cosmos Update 1990.

Carl Sagan's final piece to camera for the series.

Pale Blue Dot (1994)

Pale Blue Dot: A Vision of the Human Future in Space

Look again at that dot That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives...

• Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there-on a mote of dust suspended in a sunbeam.

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds.

Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe:, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.

The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.

It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we've ever known.

Pages 8-9, Supplemental image at randi.org

The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate... Like it or not, for the moment the Earth is where we make our stand.

• Ann Druyan suggest an experiment: Look back again at the pale blue dot of the preceding chapter. Take a good long look at it. Stare at the dot for any length of time and then try to convince yourself that God created the whole Universe for one of the 10 million or so species of life that inhabit that speck of dust. Now take it a step further: Imagine that everything was made just for a single shade of that species, or gender, or ethnic or religious subdivision. If this doesn't strike you as unlikely, pick another dot. Imagine it to be inhabited by a different form of intelligent life. They, too, cherish the notion of a God who has created everything for their benefit. How seriously do you take their claim?
  • Page 11

• It took the Church until 1832 to remove Galileo's work from its list of books which Catholics were forbidden to read at the risk of dire punishment of their immortal souls.
  • Page 43

• We've tended in our cosmologies to make things familiar. Despite all our best efforts, we've not been very inventive. In the West, Heaven is placid and fluffy, and Hell is like the inside of a volcano. In many stories, both realms are governed by dominance hierarchies headed by gods or devils. Monotheists talked about the king of kings. In every culture we imagined something like our own political system running the Universe. Few found the similarity suspicious.
  • Page 46

• In some respects, science has far surpassed religion in delivering awe. How is it that hardly any major religion has looked at science and concluded, "This is better than we thought! The Universe is much bigger than our prophets said, grander, more subtle, more elegant. God must be even greater than we dreamed"? Instead they say, "No, no, no! My god is a little god, and I want him to stay that way."
  • Page 50

• Once we overcome our fear of being tiny, we find ourselves on the threshold of a vast and awesome Universe that utterly dwarfs — in time, in space, and in potential — the tidy anthropocentric proscenium of our ancestors. We gaze across billions of light-years of space to view the Universe shortly after the Big Bang, and plumb the fine structure of matter. We peer down into the core of our planet, and the blazing interior of our star. We read the genetic language in which is written the diverse skills and propensities of every being on Earth. We uncover hidden chapters in the record of our origins, and with some anguish better understand our nature and prospects. We invent and refine agriculture, without which almost all of us would starve to death. We create medicines and vaccines that save the lives of billions. We communicate at the speed of light, and whip around the Earth in an hour and a half. We have sent dozens of ships to more than seventy worlds, and four spacecraft to the stars. We are right to rejoice in our accomplishments, to be proud that our species has been able to see so far, and to judge our merit in part by the very science that has so deflated our pretensions.
  • Page 53-54

It is sometimes said that scientists are unromantic...

• It is sometimes said that scientists are unromantic, that their passion to figure out robs the world of beauty and mystery. But is it not stirring to understand how the world actually works — that white light is made of colors, that color is the way we perceive the wavelengths of light, that transparent air reflects light, that in so doing it discriminates among the waves, and that the sky is blue for the same reason that the sunset is red? It does no harm to the romance of the sunset to know a little bit about it.
  • Pages 159-160

• Those who are skeptical about carbon dioxide greenhouse warming might profitably note the massive greenhouse effect on Venus. No one proposes that Venus's greenhouse effect derives from imprudent Venusians who burned too much coal, drove fuel-inefficient autos, and cut down their forests. My point is different. The climatological history of our planetary neighbor, an otherwise Earthlike planet on which the surface became hot enough to melt tin or lead, is worth considering — especially by those who say that the increasing greenhouse effect on Earth will be self-correcting, that we don't really have to worry about it, or (you can see this in the publications of some groups that call themselves conservative) that the greenhouse effect is a "hoax".
  • Page 227

Since, in the long run, every planetary society will be endangered by impacts from space, every surviving civilization is obliged to become spacefaring — not because of exploratory or romantic zeal, but for the most practical reason imaginable: staying alive.

• A scientific colleague tells me about a recent trip to the New Guinea highlands where she visited a stone age culture hardly contacted by Western civilization. They were ignorant of wristwatches, soft drinks, and frozen food. But they knew about Apollo 11. They knew that humans had walked on the Moon. They knew the names of Armstrong and Aldrin and Collins. They wanted to know who was visiting the Moon these days.
  • Page 281

• Since, in the long run, every planetary society will be endangered by impacts from space, every surviving civilization is obliged to become spacefaring — not because of exploratory or romantic zeal, but for the most practical reason imaginable: staying alive.
  • Page 371

• Imagine we could accelerate continuously at 1 g — what we're comfortable with on good old terra firma — to the midpoint of our voyage, and decelerate continuously at 1 g until we arrive at our destination. It would take a day to get to Mars, a week and a half to Pluto, a year to the Oort Cloud, and a few years to the nearest stars.
  • Page 395

A religion old or new, that stressed the magnificence of the universe as revealed by modern science, might be able to draw forth reserves of reverence and awe hardly tapped by the conventional faiths. Sooner or later, such a religion will emerge.

• The vast distances that separate the stars are providential. Beings and worlds are quarantined from one another. The quarantine is lifted only for those with sufficient self-knowledge and judgement to have safely traveled from star to star.
  • Page 398

'From unidentified pages"

• The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.

• Modern science has been a voyage into the unknown, with a lesson in humility waiting at every stop. Many passengers would rather have stayed home.

• If we crave some cosmic purpose, then let us find ourselves a worthy goal.

• How is it that hardly any major religion has looked at science and concluded, 'This is better than we thought! The Universe is much bigger than our prophets said, grander, more subtle, more elegant?' Instead they say, 'No, no, no! My god is a little god, and I want him to stay that way.' A religion old or new, that stressed the magnificence of the universe as revealed by modern science, might be able to draw forth reserves of reverence and awe hardly tapped by the conventional faiths.
  Sooner or later, such a religion will emerge.

The Demon-Haunted World (1995)

The Demon-Haunted World: Science as a Candle in the Dark

• Advances in medicine and agriculture have saved vastly more lives than have been lost in all the wars in history.
  • Chapter 1, "The Most Precious Thing"

• I worry that, especially as the Millennium edges nearer, pseudo-science and superstition will seem year by year more tempting, the siren song of unreason more sonorous and attractive. Where have we heard it before? Whenever our ethnic or national prejudices are aroused, in times of scarcity, during challenges to national self-esteem or nerve, when we agonize about our diminished cosmic place and purpose, or when fanaticism is bubbling up around us-then, habits of thought familiar from ages past reach for the controls. The candle flame gutters. Its little pool of light trembles. Darkness gathers. The demons begin to stir.
  • Chapter 2, "Science and Hope"

• If we long to believe that the stars rise and set for us, that we are the reason there is a Universe, does science do us a disservice in deflating our conceits?

• It is far better to grasp the Universe as it really is than to persist in delusion, however satisfying and reassuring.

• Credulity kills.

• Think of how many religions attempt to validate themselves with prophecy. Think of how many people rely on these prophecies, however vague, however unfulfilled, to support or prop up their beliefs. Yet has there ever been a religion with the prophetic accuracy and reliability of science? ... No other human institution comes close.

• Education on the value of free speech and the other freedoms reserved by the Bill of Rights, about what happens when you don't have them, and about how to exercise and protect them, should be an essential prerequisite for being an American citizen — or indeed a citizen of any nation, the more so to the degree that such rights remain unprotected. If we can't think for ourselves, if we're unwilling to question authority, then we're just putty in the hands of those in power. But if the citizens are educated and form their own opinions, then those in power work for us. In every country, we should be teaching our children the scientific method and the reasons for a Bill of Rights. With it comes a certain decency, humility and community spirit. In the demon-haunted world that we inhabit by virtue of being human, this may be all that stands between us and the enveloping darkness.
  • Chapter 25, "Real Patriots Ask Questions"

• Humans may crave absolute certainty; they may aspire to it; they may pretend, as partisans of certain religions do, to have attained it. But the history of science — by far the most successful claim to knowledge accessible to humans — teaches that the most we can hope for is successive improvement in our understanding, learning from our mistakes, an asymptotic approach to the Universe, but with the proviso that absolute certainty will always elude us.
  • Page 28

• appeal to ignorance — the claim that whatever has not been proved false must be true, and vice versa (e.g. There is no compelling evidence that UFOs are not visiting the Earth; therefore UFOs exist — and there is intelligent life elsewhere in the universe. Or: There may be seventy kazillion other worlds, but not one is known to have the moral advancement of the Earth, so we're still central to the Universe.) This impatience with ambiguity can be criticized in the phrase: absence of evidence is not evidence of absence.
  • Chapter 12, "The Fine Art of Baloney Detection", page 221

Billions and Billions (1997)

Billions and Billions: Thoughts of Life and Death at the Brink of the Millenium

• I never said it. Honest. Oh, I said there are maybe 100 billion galaxies and 10 billion trillion stars. It's hard to talk about the Cosmos without using big numbers. I said 'billion' many times on the Cosmos television series, which was seen by a great many people. But I never said 'billions and billions.' For one thing, it's imprecise. How many billions are 'billions and billions'? A few billion? Twenty billion? A hundred billion? 'Billions and billions' is pretty vague... For a while, out of childish pique, I wouldn't utter the phrase, even when asked to. But I've gotten over that. So, for the record, here it goes: 'Billions and billions.'
  • List of misquotations

• If we keep on with business as usual, the Earth will be warmed more every year; drought and floods will be endemic; many more cities, provinces, and whole nations will be submerged beneath the waves - unless heroic worldwide engineering countermeasures are taken. In the longer run, still more dire consequences may follow, including the collapse of the West Antarctic ice sheet, and the inundation of almost all the coastal cities on the planet.
  • Chapter 11, "Ambush: The Warming of the World"

• A central lesson of science is that to understand complex issues (or even simple ones), we must try to free our minds of dogma and to guarantee the freedom to publish, to contradict, and to experiment. Arguments from authority are unacceptable.
  • Chapter 14, "The Common Enemy".

• Widespread intellectual and moral docility may be convenient for leaders in the short term, but it is suicidal for nations in the long term. One of the criteria for national leadership should therefore be a talent for understanding, encouraging, and making constructive use of vigorous criticism.
  • Chapter 14, "The Common Enemy"

Debate transcript

"[The nuclear arms race is like] two sworn enemies standing waist deep in gasoline, one with three matches, the other with five." [2]

"I am agnostic" [3]

Misattributed

• If we are alone in the Universe, it sure seems like an awful waste of space.
  • Actual quote: "A sad spectacle. If they be inhabited, what a scope for misery and folly. If they be not inhabited, what a waste of space."
    • Thomas Carlyle, on other stars
    • Attributed by Carl Sagan at a November 20, 1972 symposium on "Life Beyond Earth and the Mind of Man", held at Boston University
    • Berendzen, Richard, ed. (1973). Life Beyond Earth and the Mind of Man. Washington, DC: NASA Scientific and Technical Information Office. LCCN 73-600150.  
    • "Life Beyond Earth and the Mind of Man 1975" c. 0:02:50. Google Video. Retrieved on 2006-09-11. Edited version of symposium, released by National Archives, under Google Video partnership.

• Atheism is more than just the knowledge that gods do not exist, and that religion is either a mistake or a fraud. Atheism is an attitude, a frame of mind that looks at the world objectively, fearlessly, always trying to understand all things as a part of nature.
  • Appears in this essay:
    • Emmett F. Fields. "Atheism: An Affirmative View (1980)".

External links

Wikipedia has an article about:

Carl Sagan

Wikimedia Commons has media related to:

Carl Sagan

• The Carl Sagan Portal
• Carl Sagan at the Internet Movie Database
• Can We Know the Universe? – 1979 essay by Carl Sagan, taken from his book Broca's Brain
• Talk of the Nation – Ira Flatow interviews Sagan on his book The Demon-Haunted World: Science as a Candle in the Dark (May 3, 1996)
• Skeptical Inquirer: Carl Sagan's Life & Legacy (Jan./Feb. 2007)
• We Are Here: The Pale Blue Dot – A short film narrated by Carl Sagan (40 min extended version)
• Charlie Rose interviews
• Carl Sagan – Quotes on Religion
• Profile at Findagrave.com