Carl Sagan

Carl Edward Sagan (November 9, 1934 – December 20, 1996) was an American astronomer, planetary scientist, cosmologist, astrophysicist, astrobiologist, science communicator, author, and professor. He is best known for his research on the possibility of extraterrestrial life and his contributions to understanding the greenhouse effect on Venus. Sagan assembled the Pioneer plaque and the Voyager Golden Record, which were messages sent into space to potentially be understood by extraterrestrial intelligence. He worked as an assistant professor at Harvard before moving to Cornell, where he spent most of his career. Sagan authored and co-authored hundreds of scientific papers and articles, and was a prolific writer in the field of popular science.