Comet begins with a breathtaking journey through space astride a comet. Pulitzer Prize-winning astronomer Carl Sagan, author of Cosmos and Contact, and writer Ann Druyan explore the origin, nature, and future of comets, and the exotic myths and portents attached to them. The authors show how comets have spurred some of the great discoveries in the history of science and raise intriguing questions about these brilliant visitors from the interstellar dark.

Were the fates of the dinosaurs and the origins of humans tied to the wanderings of a comet?

Dr. Carl Sagan takes us on a great adventure, offering his vivid and startling insight into the brain of man and beast, the origin of human intelligence, the function of our most haunting legends - and their amazing links to recent discoveries.

The late great astronomer and astrophysicist describes his personal search to understand the nature of the sacred in the vastness of the cosmos. Exhibiting a breadth of intellect nothing short of astounding, Sagan presents his views on a wide range of topics, including the likelihood of intelligent life on other planets, creationism and so-called intelligent design.

World renowned scientist Carl Sagan and acclaimed author Ann Druyan have written a Roots for the human species, a lucid and riveting account of how humans got to be the way we are. It shows with humor and drama that many of our key traits - self-awareness, technology, family ties, submission to authority, hatred for those a little different from ourselves, reason, and ethics - are rooted in the deep past, and illuminated by our kinship with other animals.

In the final book of his astonishing career, Carl Sagan brilliantly examines the burning questions of our lives, our world, and the universe around us. These luminous, entertaining essays travel both the vastness of the cosmos and the intimacy of the human mind, posing such fascinating questions as how did the universe originate and how will it end, and how can we meld science and compassion to meet the challenges of the coming century?

Carl Sagan, writer and scientist, returns from the frontier to tell us about how the world works. In his delightfully down-to-earth style, he explores and explains a mind-boggling future of intelligent robots, extraterrestrial life and its consequences, and other provocative, fascinating quandaries of the future that we want to see today.

In Cosmos, the late astronomer Carl Sagan cast his gaze over the magnificent mystery of the Universe and made it accessible to millions of people around the world. Now in this stunning sequel, Carl Sagan completes his revolutionary journey through space and time.

In 1982, Professors Sagan and Turco made known their discovery of the concept "nuclear winter", a widespread cold and dark, resulting in agricultural collapse and world famine, that would be generated in even a "small" nuclear war. It was a landmark discovery that revealed in the starkest terms how vulnerable our civilization is to the long-term environmental effects of nuclear war.

In 1977, two extraordinary spacecraft called Voyager were launched to the stars. Affixed to each Voyager craft was a gold-coated copped phonograph record as a message to possible extra-terrestrial civilizations that might encounter the spacecraft in some distant space and time.

This recording features the highlights of this historic 1995 event sponsored by the Temple of Understanding and includes a talk by the late cosmologist Carl Sagan. Visions for the 21st Century was a powerful forum for religious leaders, diplomats, nongovernmental organizations, and educators to present their visions for the next century.

In this illuminating audiobook, Tyson and coauthor James Trefil, a renowned physicist and science popularizer, take on the big questions that humanity has been posing for millennia - How did life begin? What is our place in the universe? Are we alone? - and provide answers based on the most current data, observations, and theories.

The Pleasure of Finding Things Out is a magnificent treasury of the best short works of Richard P. Feynman, from interviews and speeches to lectures and printed articles. A sweeping, wide-ranging collection, it presents an intimate and fascinating view of a life in science - a life like no other. From his ruminations on science in our culture to his Nobel Prize acceptance speech, this book will delight anyone interested in the world of ideas.

Are there other dimensions beyond our own? Is time travel possible? Can we change the past? Are there gateways to parallel universes? All of us have pondered such questions, but there was a time when scientists dismissed these notions as outlandish speculations. Not any more. Today, they are the focus of the most intense scientific activity in recent memory. In Hyperspace, Michio Kaku offers the first book-length tour of the most exciting (and perhaps most bizarre) work in modern physics.

In the year AD 3000, Earth is a dystopian wasteland, plundered of its natural resources by alien conquerors known as Psychlos. Fewer than 35,000 humans survive in a handful of communities scattered across the face of a post-apocalyptic Earth. From the ashes of humanity rises a young hero, Jonnie Goodboy Tyler. Setting off on an initial quest to discover a hidden evil, Jonnie unlocks the mystery of humanity’s demise and unearths a crucial weakness in their oppressors.

How do trees live? Do they feel pain or have awareness of their surroundings? Research is now suggesting trees are capable of much more than we have ever known. In The Hidden Life of Trees, forester Peter Wohlleben puts groundbreaking scientific discoveries into a language everyone can relate to.

My Big TOE: Awakening, written by a nuclear physicist in the language of contemporary culture, unifies science and philosophy, physics and metaphysics, mind and matter, purpose and meaning, the normal and the paranormal. The entirety of human experience (mind, body, and spirit) including both our objective and subjective worlds is brought together under one seamless scientific understanding.

Chemistry and Our Universe: How It All Works is your in-depth introduction to this vital field, taught through 60 engaging half-hour lectures that are suitable for any background or none at all. Covering a year’s worth of introductory general chemistry at the college level, plus intriguing topics that are rarely discussed in the classroom, this amazingly comprehensive course requires nothing more advanced than high-school math. Your guide is Professor Ron B. Davis, Jr., a research chemist and award-winning teacher at Georgetown University.

Richard Dawkins' brilliant reformulation of the theory of natural selection has the rare distinction of having provoked as much excitement and interest outside the scientific community as within it. His theories have helped change the whole nature of the study of social biology, and have forced thousands to rethink their beliefs about life.

How the Earth Works takes you on an astonishing journey through time and space. In 48 lectures, you will look at what went into making our planet - from the big bang, to the formation of the solar system, to the subsequent evolution of Earth.

We are in the midst of a global mental health crisis, and mental illnesses are on the rise. But what causes mental illness? And why are mental health problems so hard to treat? Drawing on decades of research, Harvard psychiatrist Dr. Chris Palmer outlines a revolutionary new understanding that for the first time unites our existing knowledge about mental illness within a single framework: mental disorders are metabolic disorders of the brain. Brain Energy will transform the field of mental health, and the lives of countless people around the world.

Astrophysicist Neil deGrasse Tyson has attracted one of the world’s largest online followings with his fascinating, widely accessible insights into science and our universe. Now, Tyson invites us to go behind the scenes of his public fame by unveiling his candid correspondence with people across the globe who have sought him out in search of answers. In this hand-picked collection of 100 letters, Tyson draws upon cosmic perspectives to address a vast array of questions about science, faith, philosophy, life, and of course, Pluto.

Hilarious, fascinating, and a roller coaster of dizzying, historical what-ifs, Napoleon's Hemorrhoids is a potpourri for serious historians and casual history buffs. In one of Phil Mason's many revelations, you'll learn that Communist jets were two minutes away from opening fire on American planes during the Cuban missile crisis, when they had to turn back as they were running out of fuel. You'll discover that before the Battle of Waterloo, Napoleon's painful hemorrhoids prevented him from mounting his horse to survey the battlefield.

Dr. Catherine Kleier invites us to open our eyes to the phenomenal world of plant life and to the process she calls “Natura Revelata”, the joy of celebrating and learning from the secrets of nature. As Dr. Kleier shares her knowledge with contagious excitement for her subject, she emphasizes the middle ground: Instead of focusing on cell microbiology or the study of ecosystems and habitats, she stresses the basic biology, function, and the amazing adaptations of the plants we see all around us.

In this illuminating audiobook, Tyson and coauthor James Trefil, a renowned physicist and science popularizer, take on the big questions that humanity has been posing for millennia - How did life begin? What is our place in the universe? Are we alone? - and provide answers based on the most current data, observations, and theories.

At the end of his career, Albert Einstein was pursuing a dream far more ambitious than the theory of relativity. He was trying to find an equation that explained all physical reality - a theory of everything. Experimental physicist and award-winning educator Dr. Don Lincoln takes you on this exciting journey in The Theory of Everything: The Quest to Explain All Reality. Suitable for the intellectually curious at all levels and assuming no background beyond basic high-school math, these 24 half-hour lectures cover recent developments at the forefront of particle physics and cosmology.

In the final book of his astonishing career, Carl Sagan brilliantly examines the burning questions of our lives, our world, and the universe around us. These luminous, entertaining essays travel both the vastness of the cosmos and the intimacy of the human mind, posing such fascinating questions as how did the universe originate and how will it end, and how can we meld science and compassion to meet the challenges of the coming century?

In Cosmos, the late astronomer Carl Sagan cast his gaze over the magnificent mystery of the Universe and made it accessible to millions of people around the world. Now in this stunning sequel, Carl Sagan completes his revolutionary journey through space and time.

Cosmos is one of the bestselling science books of all time. In clear-eyed prose, Sagan reveals a jewel-like blue world inhabited by a life form that is just beginning to discover its own identity and to venture into the vast ocean of space.

World renowned scientist Carl Sagan and acclaimed author Ann Druyan have written a Roots for the human species, a lucid and riveting account of how humans got to be the way we are. It shows with humor and drama that many of our key traits - self-awareness, technology, family ties, submission to authority, hatred for those a little different from ourselves, reason, and ethics - are rooted in the deep past, and illuminated by our kinship with other animals.

This recording features the highlights of this historic 1995 event sponsored by the Temple of Understanding and includes a talk by the late cosmologist Carl Sagan. Visions for the 21st Century was a powerful forum for religious leaders, diplomats, nongovernmental organizations, and educators to present their visions for the next century.