Dr. Carl Sagan, best known for his acclaimed public television series "Cosmos," poses with a model of the Viking lander in Death Valley, Calif. Image credit: NASA
Dr. Carl Sagan, best known for his acclaimed public television series “Cosmos,” poses with a model of the Viking lander in Death Valley, Calif.Image credit: “COSMOS• A PERSONAL VOYAGE “/ Druyan-Sagan Associates, Inc.