Planetary Scientist, Cornell University

"Imagination will often carry us to worlds that never were. But without it we go nowhere," Carl said.

Carl Sagan was an astronomer and a Pulitzer Prize winning author who was often described as "the scientist who made the universe clearer to the ordinary person."

Carl helped to popularize science through the writing of hundreds of articles and over two dozen books. His television series Cosmos was one the most watched show in public television history. It was seen by more than 500 million people in 60 different countries.

Carl was born in New York City on November 9, 1934. He described himself as a childhood science fiction addict who became fascinated by astronomy when he learned that every star in the night sky was a distant Sun. He was always encouraged by his parents to research answers to his innumerable questions about science.

His scientific curiosity led him to earn four degrees in physics, astronomy and astrophysics from the University of Chicago.

Carl taught and conducted research at Harvard University. He was among the first to determine that life could have existed on Mars. In 1968, Dr. Sagan became a professor at Cornell University where he was also director of the Laboratory for Planetary Studies. He was well-known as a pioneer in the field of exobiology, the study of the possibility of extraterrestrial life. He constantly appealed to NASA to extend its exploration of the universe.

In his role as a visiting scientist at the Jet Propulsion Laboratory in Pasadena, Carl helped design and manage the Mariner 2 mission to Venus, the Mariner 9 and Viking 1 and Viking 2 trips to Mars, the Voyager 1 and Voyager 2 missions to the outer solar system and the Galileo mission to Jupiter.

"Carl was one of the greatest intellects behind the genesis of space exploration generally and specifically the Galileo mission," said Dr. Torrence Johnson, a Galileo mission team member. "He was part of the original group that got together to promote the mission to NASA and he served as an interdisciplinary scientists on the mission team from the beginning. He was a great human being who shared with everyone his excitement about the exploration of the universe."

Carl suffered from a rare bone marrow disease called myelodysplasia. Complications from the disease caused the pneumonia which ended his life on December 20,1996. He was 62.

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