Carl Sagan was an American astonomer, cosmologist, astrophysicist, astrobiologist, author, science popularizer, and science communicator in astronomy and other natural sciences. Carl Sagan is best known as a science popularizer and communicator. https://www.youtube.com/watch?v=hcCVe5MamN4 In 1980 Sagan co-wrote and narrated the award-winning 13-part television series 'Cosmos: A Personal Voyage', which became the most widely watched series in the history of American public television. The ...