Carl Edward Sagan

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Carl Edward Sagan

1934-1996

American Astronomer and Biologist

For most teenagers and adults living in the 1970s, the idea of space exploration was synonymous with the name Carl Sagan. His enormously popular television series Cosmos and his many appearances on the "Tonight" show made him a recognizable figure wherever he went. Corey S. Powell, staff writer for the Scientific American, estimated that Cosmos reached an audience of over 500 million people.

Sagan's parents, Samuel and Rachel Sagan, were living in the Bensonhurst area of Brooklyn, New York, when their son, Carl, was born in 1934. Although the elder Sagan hoped that his son would follow him in the coat business, young Carl spent his early years immersed in reading science fiction and related topics: astronomy, chemistry, physics, and the likelihood of space travel.

The family moved to Rahway, New Jersey, just before Sagan entered high school, but he elected to attend college at the University of Chicago and received both his undergraduate and graduate degrees there. Part of his Ph.D. dissertation was a "greenhouse model" for Venus that indicated the possibility of sustaining human life there as well as on the Moon. This theme would run throughout his sparkling career; he argued constantly for funding and academic research for any signs of extraterrestrial life.

His first book, The Cosmic Connection, enjoyed wild success. He wrote about exceedingly complex subject matter and made it both understandable and intriguing to people in all walks of life. Later, in 1985, he published two books: Nuclear Winter and Contact. The latter was made into a successful motion picture in 1998.

Although he was well-known in scientific circles for his valuable contributions to the U.S. space program, outsiders were not often aware of the specific projects in which he was deeply involved. While NASA was working on Pioneer 10 and 11 spacecraft intended to reach Jupiter and Saturn, the project engineers called on Sagan to devise a series of messages that might be picked up by other possible civilizations as the vehicles drifted into other galaxies over millions of years. The messages Sagan devised took the form of a plaque that showed a galaxy map and the location of Earth on the map as well as drawings of a man and woman.

When NASA went on to develop the two Voyager interstellar ships, Sagan led a group that updated and improved the original messages carried in the Pioneer ships. Along with written signals, the new package included photographs of our planet and some of the people who live here, samples of our music, and multi-language greetings for those who might encounter Voyager over the eons to come.

Carl Sagan's intellectual gifts ranged far beyond astronomy and astrophysics. He was also a competent biologist (his first wife, Lynn Margulis (1938- ), is eminent in this field), a Pulitzer prize-winning, best-selling author, and a compelling personality in the world of television, where the competition was not only heavy but constant. He was also a charismatic professor at Cornell University, where he was Associate Director of the Center for Radio Physics and Space Research. (He had worked earlier at the Smithsonian Astrophysical Observatory.) Until the day he died, he was David Duncan Professor of Astronomy and Space Sciences and director of the Laboratory for Planetary Studies, both at Cornell. During his tenure at the university, he developed what was then an entirely new field: exobiology—the study of possible alien biochemistry and life forms. Sagan died in 1996.

BROOK ELLEN HALL

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