Carl Sagan 1934–1996

American scientist, nonfiction writer, novelist, and critic.

The following entry presents an overview of Sagan's career through 1997. See also Carl Sagan Criticism (Volume 30).

An internationally renowned astronomer, Sagan is among the most influential popular interpreters of science in recent times. Best known for his role as the host of the award-winning television documentary Cosmos, Sagan is also recognized for his efforts to win credibility for the scientific search for extraterrestrial life and as a leading advocate for nuclear arms reduction. The best-selling author of The Cosmic Connection (1973), The Dragons of Eden (1977), Cosmos (1980), and the novel Contact (1985), Sagan celebrated the joy of scientific discovery and captured the imagination of a mass audience with his compelling speculations on the mechanizations of the universe and evolution of human life.

Biographical Information

Born Carl Edward Sagan in New York, Sagan was raised by his Russian-immigrant father, a garment cutter, and American-born mother in the Bensonhurst section of the city. Fascinated with the night sky as a youth, Sagan became engrossed in science fiction, particularly the novels of Edgar Rice Burroughs, and at age twelve announced to his grandfather his desire to become an astronomer. Four years later he left for the University of Chicago on a scholarship, where he earned an undergraduate degree in 1954 and a Ph.D. in astronomy and astrophysics in 1960. While at Chicago, Sagan earned a reputation as a nonconformist and even organized his own series of campus lectures. In 1957, Sagan married his first wife, scientist Lynn Alexander; a second marriage to Linda Salzman in 1968 also ended in divorce, and was followed by a third marriage to writer Ann Druyan. In 1960, Sagan began his scientific career as a research fellow in astronomy at the University of California at Berkeley. There he developed important hypotheses about the surface temperature of Venus and Martian wind storms. He then took up a teaching position at Harvard University while working at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts. Denied tenure at Harvard, Sagan left for Cornell University in 1968, where he worked as a teacher and director of the Laboratory for Planetary Studies until his death in 1996. Sagan also contributed to the de-velopment of NASA space-probe projects over several decades, including the unmanned Mariner 9 and Viking missions to Mars and subsequent Pioneer and Voyager missions to distant planets. His first major publication, Intelligent Life in the Universe (1963), was followed by the success of The Cosmic Connection, The Dragons of Eden, winner of a Pulitzer Prize in 1978, and Broca's Brain (1979). A popular guest on the talk show circuit, Sagan's fame as the unofficial spokesperson for the scientific community grew in 1980 with the PBS television program Cosmos, a thirteen-part series in which Sagan traversed a computer-simulated galaxy in search of the origins of the universe and life—both human and extraterrestrial. His book Cosmos, based on the television series, won a Hugo Award in 1982. Sagan's only novel, Contact, winner of a Locus Award, was adapted as a film in 1996. In his late works, Shadows of a Forgotten Ancestor (1992), Pale Blue Dot (1994), The Demon-Haunted World (1995), and Billions and Billions (1997), Sagan continued to take on the central mysteries of human nature and existence. He was also a prolific contributor to both scientific journals and popular magazines. He died in Seattle, Washington, of pneumonia, a complication resulting from myelodysplasia, a bone marrow disease from which he was recovering.

Major Works

Sagan's popular writings on the promise of modern science won wide appeal largely for their unusual ability to translate complex subjects into awe-inspiring commentaries on the possibility of space travel, human evolution, and life on other planets. With the publication of Intelligent Life in the Universe, a translation and abridgement of the work by Russian astrophysicist I. S. Shklovskii, Sagan emerged as a leading spokesperson for exobiology, the study of extraterrestrial environments and potential life forms. The book was one of the first of its kind to take the subject seriously. The Cosmic Connection provides a comprehensive outline of recent advances in planetary science, including the probable origins of the universe, stars and planets, and life on Earth. Sagan further expanded his ambitious investigations into the design and evolution of the universe in his television program and book Cosmos, both of which feature a semi-omniscient Sagan as cosmic guide and instructor aided by stunning intergalactic illustrations and photographs. Pale Blue Dot similarly explores the birth of the universe and solar system, space travel, and the future colonization of other planets through "terraforming." The title alludes to an astonishing photograph of Earth taken by the Voyager space-probe as it left the solar system, drawing attention to the humbling revelation that our planet is merely one among countless others. In A Path Where No Man Thought (1989), a collaboration with atmospheric scientist Richard Turco, Sagan reexamines the threat of nuclear war and the implications of "nuclear winter," a theory developed by Sagan and several other experts in 1983. According to their research, a massive nuclear strike could produce enough smoke to obscure the sun, resulting in a darkened, frigid, and uninhabitable world. Published as the Cold War drew to an end, in the book Sagan and Turco warn against the continuing danger of nuclear holocaust and recommend drastic reductions in U.S. and Soviet nuclear arsenals to a level of "minimum sufficient deterrence." In The Dragons of Eden, Sagan discusses contemporary neurophysiology and the genetic origin of human intelligence. His speculation, largely concerned with the history of human behavior, focuses on the interplay among three hypothetical stages of human brain development: the first and lowest is the reptilian R-complex, a vestige of our pre-mammalian progenitors that is responsible for aggression and ritual; the second is the limbic system, similar to that of birds and lower-order mammals, from which emotions and religion derive; the third and highest is the more developed neocortex or primate brain. Shadows of Forgotten Ancestors, co-written with his wife Ann Druyan, is a highly readable survey of human evolution, covering the birth of the solar system, formation of DNA, and study of physiological and behavioral similarities among humans and primates. Broca's Brain, named after nineteenth-century anatomist Paul Broca, who identified the source of articulate speech in the frontal lobe, contains a diverse collection of essays on the solar system, planetary exploration, robots, extraterrestrial intelligence, famous scientists, pseudoscience and religion, and a call for greater public support for science and technology. In The Demon-Haunted World, Sagan holds the verifiable achievements of science and scientific method against dubious, unsubstantiated examples of phenomena and superstition. Seeking to demystify stories of UFO sightings, alien abductions, miracles, astrology, and New Age versions of spirituality, Sagan exalts the superiority of empirical testing and the ability of certain branches of science to predict the future. Revealing his abiding interest in the search for extraterrestrial life, Contact, his only work of fiction, explores the possibility of communication with a distant planet. In this science fiction thriller, scientists receive radio transmissions from the star system Vega. From these signals, in the form of rebounded television images of Hitler's 1936 Olympic games, they are able to decrypt mathematical instructions for the construction of a spacecraft. After two failed launches, an international crew is transported to an Earth-like environment where they encounter doppelgangers and apparitions. Discredited upon their return—Earth witnesses note that the vehicle never left the ground and their entire excursion lasted only twenty minutes—an American member of the crew, Eleanor Arroway, seeks to verify their voyage and discovers God's signature in a mathematical extrapolation of pi.

Critical Reception

Sagan is consistently praised for his great ability to communicate the esoteric dilemmas and discoveries of modern science to a general audience. In addition, he is highly regarded for his significant contributions to the study of Mars and Venus, NASA space exploration, and the nuclear disarmament movement. However, criticized and even resented by some members of the scientific community, he has been derided for his controversial interest in extraterrestrial life and accused of oversimplifying complex subjects to the point of inaccuracy for his nonspecialist viewers and readers. Others object to Sagan's materialist view of evolution, tendency toward reductionism, vehement denial of a godlike creator, and glorification of technological progress and the primacy of human reason. Despite his detractors, Sagan's infectious enthusiasm for science and dauntless speculation on the great mysteries of our cosmic origins inspired renewed public interest in the scientific enterprise. Along with Jacob Bronowski and Stephen Jay Gould, Sagan is credited for the popularization of science in the twentieth century.