Biography

American astronomer and astrophysicist (1934–1996), Carl Sagan is celebrated for bringing science to the general public. His television series *Cosmos* (1980) reached hundreds of millions of viewers worldwide.

Carl Sagan(1934 — 1996)

Carl Sagan

États-Unis

9 min read

SciencesLiteratureCultureAstronomeÉcrivain(e)20th CenturyCold War, space race, rise of science communication

Frequently asked questions

Carl Sagan (1934-1996) was an American astronomer and astrophysicist who revolutionized science communication. What is worth remembering is that he made science accessible to hundreds of millions of people through his series Cosmos (1980). Unlike many researchers of his time, Sagan believed that sharing knowledge with the general public was just as important as research itself.

Famous Quotes

« We are made of star-stuff.»
« Absence of evidence is not evidence of absence.»
« The Earth is a very small stage in a vast cosmic arena.»

Key Facts

  • 1934: born in Brooklyn, New York
  • 1968: professor at Cornell University, specialist in planetary atmospheres
  • 1980: broadcast of the series *Cosmos: A Personal Voyage*, watched by 500 million people
  • 1985: publication of the novel *Contact*, adapted for the cinema in 1997
  • 1994: Pulitzer Prize for *The Demon-Haunted World* (a defense of rational thinking)

Works & Achievements

The Dragons of Eden: Speculations on the Evolution of Human Intelligence (1977)

A popular science book on the evolution of the human brain, which earned Sagan the Pulitzer Prize in 1978. This book illustrates his ability to make complex scientific and philosophical questions accessible to a very wide audience.

Cosmos: A Personal Voyage (television series) (1980)

A 13-episode documentary series co-written and hosted by Sagan, tracing the history of the universe and of human science. Watched by more than 500 million people in 60 countries, it remains one of the greatest works of science communication of the 20th century.

Cosmos (book) (1980)

The companion book to the television series, weaving together astronomy, physics, and the history of science into a poetic and accessible narrative. It sold more than 5 million copies and remained at the top of bestseller lists in the United States for several years.

Contact (novel) (1985)

A science fiction novel in which an astronomer receives a message from an extraterrestrial civilization. Adapted for film in 1997, it explores themes of science, religion, and the search for extraterrestrial intelligence with a scientific rigor rare in the genre.

Pale Blue Dot: A Vision of the Human Future in Space (1994)

Inspired by the famous photograph of Earth taken by Voyager 1, this book makes the case for space exploration and argues that humanity must become a multi-planetary species in order to ensure its long-term survival.

The Demon-Haunted World: Science as a Candle in the Dark (1995)

Sagan's last major work, published a year before his death, defending scientific thinking and critiquing pseudoscience and superstition. Regarded as his intellectual testament and one of the defining texts in defense of reason in the 20th century.

Anecdotes

Carl Sagan was one of the designers of the Pioneer plaques (1972) and the Voyager Golden Records (1977), sent aboard space probes in the hope of contacting potential extraterrestrial civilizations. These objects contained information about humanity, its position in the universe, as well as sounds, music, and images of Earth.

In 1983, Sagan was one of the authors of the scientific study on “nuclear winter”: the researchers demonstrated that a nuclear conflict would generate dust clouds capable of blocking sunlight for years, threatening all life on Earth. This publication had a considerable impact on international disarmament negotiations.

His television series Cosmos: A Personal Voyage (1980) was watched by more than 500 million people in over 60 countries, becoming at the time the most widely broadcast documentary series in the history of American television. Sagan presented astronomy with a contagious passion that inspired entire generations of scientists.

In 1990, Sagan convinced NASA to turn the camera of the Voyager 1 probe — then more than 6 billion kilometers from Earth — to photograph our planet. In this image, Earth appears as nothing more than a tiny bluish dot in the vastness of space — what Sagan called the “Pale Blue Dot,” a symbol of humanity’s fragility and solitude in the cosmos.

Carl Sagan testified before the United States Congress on multiple occasions to advocate for space research funding and to warn lawmakers about the dangers of the nuclear arms race. He was also one of the co-founders of the Planetary Society in 1980, an organization dedicated to space exploration and the search for extraterrestrial life.

Primary Sources

Cosmos — companion book to the television series (1980)
The cosmos is all that is or ever was or ever will be. Our feeblest contemplations, our grandest loves, our most shattering religious ecstasies, our deepest thoughts — all are mere vibrations of air, atoms interacting in the dark recesses of your skull.
Pale Blue Dot: A Vision of the Human Future in Space (1994)
Look again at that dot. That's here. That's home. That's us. Everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives on a mote of dust suspended in a sunbeam.
Nuclear Winter: Global Consequences of Multiple Nuclear Explosions (Science journal, vol. 222) (1983)
Calculations show that nuclear exchanges in the megaton range would plunge the Earth into prolonged darkness and cold, capable of destroying most agricultural crops in the Northern Hemisphere, with potentially catastrophic consequences for the world population.
The Demon-Haunted World: Science as a Candle in the Dark (1995)
Science is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, able to tell us the truth about the world — self-correcting, never finished.
Testimony before the U.S. Senate on the dangers of nuclear armament (1983)
We have produced weapons of mass destruction in quantities sufficient to destroy human civilization many times over. The most elementary prudence requires that we seriously consider the long-term consequences of our nuclear arsenal.

Key Places

Brooklyn, New York, United States

Carl Sagan was born on November 9, 1934, in Brooklyn, into a Jewish immigrant family. It was during a childhood visit to the Hayden Planetarium in Manhattan that he developed his passion for astronomy and the universe.

Cornell University, Ithaca, New York, United States

Sagan joined Cornell in 1968 as a professor of astronomy and director of the Laboratory for Planetary Studies. Cornell became the center of his academic career, his research into extraterrestrial life, and his family life until his death.

Jet Propulsion Laboratory (JPL), Pasadena, California, United States

Sagan worked closely with this NASA facility on the Pioneer, Viking, and Voyager missions. There he designed messages intended for extraterrestrial beings and took part in analyzing the planetary data returned by the probes.

University of Chicago, Illinois, United States

Sagan earned his bachelor's degree, master's degree, and doctorate in astronomy and astrophysics here (1960). Trained by leading scientists, he developed his earliest insights into the possibility of life elsewhere in the universe.

Seattle, Washington, United States

Carl Sagan died on December 20, 1996, in Seattle at the Fred Hutchinson Cancer Research Center, from pneumonia complications related to myelodysplasia diagnosed in 1994.

See also