CARL EDWARD SAGAN (/ˈseɪɡən/ ; November 9, 1934 – December 20, 1996) was an American astronomer , cosmologist , astrophysicist , astrobiologist , author, science popularizer, and science communicator in astronomy and other natural sciences. He is best known for his work as a science popularizer and communicator. His best known scientific contribution is research on extraterrestrial life , including experimental demonstration of the production of amino acids from basic chemicals by radiation . Sagan assembled the first physical messages sent into space: the Pioneer plaque and the Voyager Golden Record , universal messages that could potentially be understood by any extraterrestrial intelligence that might find them. Sagan argued the now accepted hypothesis that the high surface temperatures of Venus can be attributed to and calculated using the greenhouse effect .
Sagan published more than 600 scientific papers and articles and was author, co-author or editor of more than 20 books. He wrote many popular science books, such as _ The Dragons of Eden _, _Broca\'s Brain _ and _ Pale Blue Dot _, and narrated and co-wrote the award-winning 1980 television series _Cosmos: A Personal Voyage _. The most widely watched series in the history of American public television , _Cosmos_ has been seen by at least 500 million people across 60 different countries. The book _ Cosmos _ was published to accompany the series. He also wrote the science fiction novel _Contact _, the basis for a 1997 film of the same name . His papers, containing 595,000 items, are archived at The Library of Congress .
Sagan advocated scientific skeptical inquiry and the scientific method , pioneered exobiology and promoted the Search for Extra-Terrestrial Intelligence ( SETI ). He spent most of his career as a professor of astronomy at Cornell University , where he directed the Laboratory for Planetary Studies . Sagan and his works received numerous awards and honors, including the NASA Distinguished Public Service Medal , the National Academy of Sciences Public Welfare Medal , the Pulitzer Prize for General Non-Fiction for his book _The Dragons of Eden_, and, regarding _Cosmos: A Personal Voyage_, two Emmy Awards , the Peabody Award and the Hugo Award . He married three times and had five children. After suffering from myelodysplasia , Sagan died of pneumonia at the age of 62, on December 20, 1996.
* 1 Early life
* 1.1 1939 World\'s Fair * 1.2 World War II * 1.3 Inquisitiveness about nature * 1.4 High school years
* 2 Education * 3 Scientific career * 4 Scientific achievements
* 5 _Cosmos_: popularizing science on TV
* 5.1 "Billions and billions"
* 6 Scientific and critical thinking advocacy
* 6.1 Popularizing science * 6.2 Criticisms
* 7 Social concerns * 8 Personal life and beliefs * 9 Sagan and UFOs * 10 Death * 11 Posthumous recognition * 12 Awards and honors * 13 Publications * 14 See also * 15 Notes * 16 References * 17 Further reading * 18 External links
Carl Sagan was born in Brooklyn , New York. His father, Samuel Sagan, was an immigrant garment worker from Kamianets-Podilskyi , then in the Russian Empire , in today's Ukraine . His mother, Rachel Molly Gruber, was a housewife from New York. Carl was named in honor of Rachel's biological mother , Chaiya Clara, in Sagan's words, "the mother she never knew."
He had a sister, Carol, and the family lived in a modest apartment near the Atlantic Ocean, in Bensonhurst , a Brooklyn neighborhood. According to Sagan, they were Reform Jews , the most liberal of North American Judaism's four main groups. Both Sagan and his sister agreed that their father was not especially religious, but that their mother "definitely believed in God, and was active in the temple ... and served only kosher meat." :12 During the depths of the Depression , his father worked as a theater usher.
According to biographer Keay Davidson, Sagan's "inner war" was a result of his close relationship with both of his parents, who were in many ways "opposites." Sagan traced his later analytical urges to his mother, a woman who had been extremely poor as a child in New York City during World War I and the 1920s. :2 As a young woman she had held her own intellectual ambitions, but they were frustrated by social restrictions: her poverty, her status as a woman and a wife, and her Jewish ethnicity. Davidson notes that she therefore "worshipped her only son, Carl. He would fulfill her unfulfilled dreams." :2
However, he claimed that his sense of wonder came from his father. In his free time he gave apples to the poor or helped soothe labor-management tensions within New York's garment industry. :2 Although he was awed by Carl's intellectual abilities, he took his son's inquisitiveness in stride and saw it as part of his growing up. :2 In his later years as a writer and scientist, Sagan would often draw on his childhood memories to illustrate scientific points, as he did in his book, _Shadows of Forgotten Ancestors _. :9 Sagan describes his parents' influence on his later thinking: My parents were not scientists. They knew almost nothing about science. But in introducing me simultaneously to skepticism and to wonder, they taught me the two uneasily cohabiting modes of thought that are central to the scientific method.
1939 WORLD\'S FAIR
Sagan recalls that one of his most defining moments was when his parents took him to the 1939 New York World\'s Fair when he was four years old. The exhibits became a turning point in his life. He later recalled the moving map of the _America of Tomorrow _ exhibit: "It showed beautiful highways and cloverleaves and little General Motors cars all carrying people to skyscrapers, buildings with lovely spires, flying buttresses—and it looked great!" :14 At other exhibits, he remembered how a flashlight that shone on a photoelectric cell created a crackling sound, and how the sound from a tuning fork became a wave on an oscilloscope . He also witnessed the future media technology that would replace radio: television. Sagan wrote: Plainly, the world held wonders of a kind I had never guessed. How could a tone become a picture and light become a noise? :14
He also saw one of the Fair's most publicized events, the burial of a time capsule at Flushing Meadows , which contained mementos of the 1930s to be recovered by Earth's descendants in a future millennium. "The time capsule thrilled Carl," writes Davidson. As an adult, Sagan and his colleagues would create similar time capsules—capsules that would be sent out into the galaxy; these were the Pioneer plaque and the _ Voyager Golden Record _ précis, all of which were spinoffs of Sagan's memories of the World's Fair. :15
WORLD WAR II
During World War II Sagan's family worried about the fate of their European relatives. Sagan, however, was generally unaware of the details of the ongoing war. He wrote, "Sure, we had relatives who were caught up in the Holocaust . Hitler was not a popular fellow in our household... But on the other hand, I was fairly insulated from the horrors of the war." His sister, Carol, said that their mother "above all wanted to protect Carl... She had an extraordinarily difficult time dealing with World War II and the Holocaust." :15 Sagan's book, _ The Demon-Haunted World _ (1996), included his memories of this conflicted period, when his family dealt with the realities of the war in Europe but tried to prevent it from undermining his optimistic spirit.
INQUISITIVENESS ABOUT NATURE
Soon after entering elementary school he began to express a strong inquisitiveness about nature. Sagan recalled taking his first trips to the public library alone, at the age of five, when his mother got him a library card. He wanted to learn what stars were, since none of his friends or their parents could give him a clear answer: I went to the librarian and asked for a book about stars ... And the answer was stunning. It was that the Sun was a star but really close. The stars were suns, but so far away they were just little points of light ... The scale of the universe suddenly opened up to me. It was a kind of religious experience. There was a magnificence to it, a grandeur, a scale which has never left me. Never ever left me. :18
At about age six or seven, he and a close friend took trips to the American Museum of Natural History across the East River in Manhattan . While there, they went to the Hayden Planetarium and walked around the museum's exhibits of space objects, such as meteorites , and displays of dinosaurs and animals in natural settings. Sagan writes about those visits: I was transfixed by the dioramas—lifelike representations of animals and their habitats all over the world. Penguins on the dimly lit Antarctic ice; ...a family of gorillas , the male beating his chest, ...an American grizzly bear standing on his hind legs, ten or twelve feet tall, and staring me right in the eye. :18
His parents helped nurture his growing interest in science by buying him chemistry sets and reading materials. His interest in space, however, was his primary focus, especially after reading science fiction stories by writers such as H. G. Wells and Edgar Rice Burroughs , which stirred his imagination about life on other planets such as Mars . According to biographer Ray Spangenburg, these early years as Sagan tried to understand the mysteries of the planets became a "driving force in his life, a continual spark to his intellect, and a quest that would never be forgotten."
In 1947 he discovered _ Astounding Science Fiction _ magazine, which introduced him to more hard science fiction speculations than those in Burroughs's novels. That same year inaugurated the "flying saucer " mass hysteria with the young Carl suspecting the "discs" might be alien spaceships.
HIGH SCHOOL YEARS
Sagan had lived in Bensonhurst where he went to David A. Boody Junior High School. He had his bar mitzvah in Bensonhurst when he turned 13. :23 The following year, 1948, his family moved to the nearby town of Rahway, New Jersey for his father's work, where Sagan then entered Rahway High School . He graduated in 1951. :23 Rahway was an older industrial town, and the Sagans were among its few Jewish families. :23 Photo of Sagan from high school yearbook, 1951
Sagan was a straight-A student but was bored due to unchallenging classes and uninspiring teachers. :23 His teachers realized this and tried to convince his parents to send him to a private school, the administrator telling them, "This kid ought to go to a school for gifted children, he has something really remarkable." :24 This they couldn't do, partly because of the cost.
Sagan was made president of the school's chemistry club, and at home he set up his own laboratory. He taught himself about molecules by making cardboard cutouts to help him visualize how molecules were formed: "I found that about as interesting as doing experiments," he said. :24 Sagan remained mostly interested in astronomy as a hobby, and in his juni