In the course of 13 fascinating hours, Cosmos spans its own galaxy of topics to serve Sagan's theme, each segment deepening our understanding of how we got from there simple microbes in the primordial mud to here space-faring civilization in the 21st century. In his "ship of the imagination," Sagan guides us to the farthest reaches of space and takes us back into the history of scientific inquiry, from the ancient library of Alexandria to the NASA probes of our neighboring planets. Upon this vast canvas Sagan presents the "cosmic calendar," placing the 15-billion-year history of the universe into an accessible one-year framework, then filling it with a stunning chronology of events, both interstellar and earthbound.

From the lives of the stars, to creation theories, functions of the human brain, and the ongoing search for extraterrestrial intelligence, Cosmos asks big questions. When appropriate, Sagan offers big answers, or asks still bigger--and yes, even spiritual--questions at the boundaries of science and religion. What's most remarkable about Cosmos is that it remains almost entirely fresh, with few updates needed to the science that Sagan so passionately celebrates. It is no exaggeration to say that Cosmos--for all the debate it may continue to provoke--is a vital document for humanity at a pivotal crossroads of our history. --Jeff Shannon