Photograph of Carl Sagan
Robert Reichert and Cornell University.

Carl Sagan

Carl Sagan is an American astronomer who was born in 1934. He is famous for his research on the origins of life and his belief that life exists elsewhere in the universe.

Sagan is a leading figure in the search for extraterrestrial intelligence. He studied the possibility of life on Titan, Saturn's largest moon, whose atmosphere has similar chemistry to that of Earth. Sagan has also played a prominent role in the U.S. space program, with his involvement in the Mariner, Viking, and Voyager spacecraft expeditions. He has made valuable contributions to our understanding of planetary atmospheres and planetary surfaces.

Sagan passed away on December 20, 1996.

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