- Person
- Carl Sagan
- Lived
- 1934–1996
- Field
- Astronomy, planetary science
- From
- American
The story
Carl Sagan began writing for general readers in the 1970s with The Cosmic Connection. His next major book grew out of the Jacob Bronowski Memorial Lecture in Natural Philosophy, which he delivered at the University of Toronto. Expanded into The Dragons of Eden: Speculations on the Evolution of Human Intelligence and published by Random House in 1977, it tackled the question of how the human brain and mind came to be.
The book drew together anthropology, evolutionary biology, psychology and computer science. Sagan discussed how intelligence might be measured, the evolution of the brain and especially the neocortex, the purpose of sleep and dreams, and experiments teaching sign language to chimpanzees. Its title came from his suggestion that our ancestors' long struggle against predators, especially reptiles, may lie behind the myths of dragons found in many cultures.
In its second chapter he introduced the Cosmic Calendar, a memorable way of picturing the history of the universe by compressing everything since the Big Bang into a single year. On that calendar the Earth does not form until early September, dinosaurs appear on Christmas Eve and flowers on December 28, and the first humans arrive only late on New Year's Eve. All of recorded history fits into the last few seconds of December 31, a vivid lesson in how recently our species arrived.
Reviewers were enthusiastic. John Leonard of The New York Times called the book a delight, and even Harold Urey, one of Sagan's harshest critics, wrote to tell him how much he liked it. The book won the 1978 Pulitzer Prize for General Nonfiction, an unusual honour for a working scientist. In 1977 Sagan also gave the Royal Institution Christmas Lectures in London, on the planets.
Sagan reused the Cosmic Calendar in his television series Cosmos, which brought it to a vast audience. Over his career he wrote many bestsellers and received 20 honorary degrees from American colleges and universities for his contributions to science, literature, education and the environment. In 2002 his son Dorion Sagan and John Skoyles published a follow-up to the book, Up from Dragons.
Why it matters
The Cosmic Calendar became one of the most widely used images in science teaching, helping students everywhere grasp the vast span of cosmic time and how recently humans appeared.
About Carl Sagan
Brooklyn-born astronomer who explained the Venus greenhouse, helped send humanity’s messages on Pioneer and Voyager, and taught Cosmos viewers worldwide to look at the universe with wonder and doubt.
More about Carl Sagan
- Carl Sagan co-founded the Planetary SocietyIn 1980 Carl Sagan co-founded the Planetary Society and became its first president, building a public movement to support the exploration of space.
- Carl Sagan explained why Venus is a furnaceIn the early 1960s Carl Sagan argued from radio data that Venus's surface was about 500 °C because of a greenhouse effect, a conclusion confirmed by Mariner 2 in 1962.
- Carl Sagan inspired a generation of science communicatorsCarl Sagan invited a 17-year-old Neil deGrasse Tyson to Cornell and taught Bill Nye astronomy, inspiring a generation of scientists and science popularisers.
- Carl Sagan showed Mars's changing colours were dustMany astronomers thought seasonal colour changes on Mars were spreading vegetation. Carl Sagan showed they were shifts in surface dust driven by windstorms.
- Carl Sagan asked Voyager to photograph the Pale Blue DotAt Carl Sagan's urging, Voyager 1 turned its camera homeward on February 14, 1990, and photographed Earth from about 6 billion kilometres away as a tiny pale blue dot.
- Carl Sagan designed humanity's first message to the starsGiven just three weeks by NASA, Carl Sagan and Frank Drake designed the Pioneer plaque, a message to any alien finders, now leaving the solar system aboard two spacecraft.
- Carl Sagan made the search for alien life respectableIn 1982 Carl Sagan published a petition in the journal Science supporting the search for extraterrestrial intelligence, signed by 70 scientists including seven Nobel laureates.
- Carl Sagan foresaw ocean worlds on Titan and EuropaCarl Sagan was among the first to suggest that Saturn's moon Titan might have surface liquids and that Jupiter's moon Europa might hide an ocean of water beneath its ice.
- Carl Sagan chaired the Voyager Golden Record committeeFor the Voyager probes launched in 1977, Carl Sagan chaired the committee that chose the Golden Record's contents, including greetings in 55 languages and 116 images of Earth.
- Carl Sagan warned Congress about climate change in 1985Drawing on his study of Venus, Carl Sagan testified to the US Congress in 1985 that the greenhouse effect would change Earth's climate.
- Kip Thorne helped Carl Sagan imagine Contact's wormholesFor his 1985 novel Contact, Carl Sagan asked his friend Kip Thorne how a wormhole might work. The book sold 1.7 million copies in two years and became a 1997 film.
- Carl Sagan's Cosmos reached 500 million peopleCosmos: A Personal Voyage, first broadcast in 1980, has been seen by at least 500 million people in 60 countries, and its companion book was the best-selling science book of its time.
- Carl Sagan gave the public a baloney detection kitIn The Demon-Haunted World (1995), Carl Sagan offered readers a toolkit for critical thinking and popularised the rule that extraordinary claims require extraordinary evidence.
- Carl Sagan warned the world about nuclear winterIn 1983 Carl Sagan co-authored the TTAPS study warning that a nuclear war could cool the planet, work honoured in 2022 with the Future of Life Award.
Sources
- Carl Sagan Wikipedia
- Carl Sagan The Planetary Society
- The Dragons of Eden Wikipedia
Another act of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.