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.

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?

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.

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.

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.

The future is here...in an adventure of cosmic dimension. In December, 1999, a multinational team journeys out to the stars, to the most awesome encounter in human history. Who - or what - is out there? In Cosmos, Carl Sagan explained the universe. In Contact, he predicts its future - and our own.

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.

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.

How can we make intelligent decisions about our increasingly technology-driven lives if we don’t understand the difference between the myths of pseudoscience and the testable hypotheses of science? Pulitzer Prize-winning author and distinguished astronomer Carl Sagan argues that scientific thinking is critical not only to the pursuit of truth but to the very well-being of our democratic institutions.

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.

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.

At first, only a few things are known about the celestial object that astronomers dub Rama. It is huge, weighing more than ten trillion tons. And it is hurtling through the solar system at inconceivable speed. Then a space probe confirms the unthinkable: Rama is no natural object. It is, incredibly, an interstellar spacecraft. Space explorers and planet-bound scientists alike prepare for mankind's first encounter with alien intelligence.

In this grand poetic vision of the universe, Lawrence Krauss tells the dramatic story of the discovery of the hidden world that underlies reality - and our place within it. Reality is not what you think or sense - it’s weird, wild, and counterintuitive, and its inner workings seem at least as implausible as the idea that something can come from nothing. With his trademark wit and accessible style, Krauss leads us to realms so small that they are invisible to microscopes, to the birth and rebirth of light, and into the natural forces that govern our existence.

When Newton discovered the law of gravity, he unified the rules governing the heavens and the Earth. Since then, physicists have been placing new forces into ever-grander theories. But perhaps the ultimate challenge is achieving a monumental synthesis of the two remaining theories—relativity and the quantum theory. This would be the crowning achievement of science, a profound merging of all the forces of nature into one beautiful, magnificent equation to unlock the deepest mysteries in science: What happened before the Big Bang?

When it comes to climate change, the media, politicians, and other prominent voices have declared that "the science is settled." In reality, the long game of telephone from research to reports to the popular media is corrupted by misunderstanding and misinformation. Core questions - about the way the climate is responding to our influence, and what the impacts will be - remain largely unanswered. The climate is changing, but the why and how aren't as clear as you've probably been led to believe.

End Times is a compelling work of skilled reportage that peels back the layers of complexity around the unthinkable - and inevitable - end of humankind. From asteroids and artificial intelligence to volcanic supereruption to nuclear war, veteran science reporter and TIME editor Bryan Walsh provides a stunning panoramic view of the most catastrophic threats to the human race.

In The Vanishing Face of Gaia, British scientist James Lovelock predicts global warming will lead to a Hot Epoch. Lovelock is best known for formulating the controversial Gaia theory in the 1970s, with Ruth Margulis of the University of Massachusetts, which states that organisms interact with and regulate Earth's surface and atmosphere. We ignore this interaction at our peril.

In this fascinating foray into the centuries-old relationship between science and military power, acclaimed astrophysicist Neil deGrasse Tyson and writer-researcher Avis Lang examine how the methods and tools of astrophysics have been enlisted in the service of war. "The overlap is strong, and the knowledge flows in both directions," say the authors, because astrophysicists and military planners care about many of the same things: multi-spectral detection, ranging, tracking, imaging, high ground, nuclear fusion, and access to space. Tyson and Lang call it a "curiously complicit" alliance.

Warnings is the story of the future of national security, threatening technologies, the US economy, and possibly the fate of civilization. In Greek mythology Cassandra foresaw calamities, but was cursed by the gods to be ignored. Modern-day Cassandras clearly predicted the disasters of Katrina, Fukushima, the Great Recession, the rise of ISIS, and many more. Like the mythological Cassandra, they were ignored. There are others right now warning of impending disasters, but how do we know which warnings are likely to be right?

This original audiobook considers one of the most extraordinary scientific and political stories of our time: how in the 1980s a handful of scientists came to believe that mankind faced catastrophe from runaway global warming, and how today this has persuaded politicians to land us with what promises to be the biggest bill in history. Christopher Booker interweaves the science of global warming with that of its growing political consequences, showing how just when the politicians are threatening to change our Western way of life beyond recognition, the scientific evidence behind the global warming theory is being challenged like never before.

In recent years our world has seen transformations of all kinds: intense climate change accompanied by significant weather extremes; deadly tsunamis caused by submarine earthquakes; unprecedented terrorist attacks; costly wars in Iraq and Afghanistan; a terrible and overlooked conflict in Equatorial Africa costing millions of lives; an economic crisis threatening the stability of the international system.

Deniers of climate change sometimes quip that claims about global warming are more about political science than climate science. They are wrong on the science, but may be right with respect to its political implications. A hotter world, writes Andrew Guzman, will bring unprecedented migrations, famine, war, and disease. It will be a social and political disaster of the first order.

Climate change has been a perplexing problem for years. Casey's research into the Sun's activity, which began almost a decade ago, resulted in discovery of a solar cycle that is now reversing from its global warming phase to that of dangerous global cooling for the next 30 years or more. This new cold climate will dramatically impact the world's citizens.

For over a decade, philosopher and energy expert Alex Epstein has predicted that any negative impacts of fossil fuel use on our climate will be outweighed by the unique benefits of fossil fuels to human flourishing--including their unrivaled ability to provide low-cost, reliable energy to billions of people around the world, especially the world’s poorest people. And contrary to what we hear from media “experts” about today’s “renewable revolution” and “climate emergency,” reality has proven Epstein right.

AI expert Yorick Wilks takes a journey through the history of artificial intelligence up to the present day, examining its origins, controversies, and achievements, as well as looking into just how it works. He also considers the future, assessing whether these technologies could menace our way of life and how we are all likely to benefit from AI applications in the years to come.

The Doomsday Machine is Ellsberg's hair-raising insider's account of the most dangerous arms buildup in the history of civilization, whose legacy - and renewal under the Obama administration - threatens the very survival of humanity. It is scarcely possible to estimate the true dangers of our present nuclear policies without penetrating the secret realities of the nuclear strategy of the late Eisenhower and early Kennedy years, when Ellsberg had high-level access to them.

In The End Is Always Near, Dan Carlin looks at questions and historical events that force us to consider what sounds like fantasy; that we might suffer the same fate that all previous eras did. Will our world ever become a ruin for future archaeologists to dig up and explore? The questions themselves are both philosophical and like something out of The Twilight Zone.

Here for the first time, in rich human, political, and scientific detail, is the complete story of how the bomb was developed, from the turn-of-the-century discovery of the vast energy locked inside the atom to the dropping of the first bombs on Japan. Few great discoveries have evolved so swiftly - or have been so misunderstood. From the theoretical discussions of nuclear energy to the bright glare of Trinity, there was a span of hardly more than 25 years.

For decades environmentalists have told us that using fossil fuels is a self-destructive addiction that will destroy our planet. Yet by every measure of human well-being, from life expectancy to clean water to climate safety, life has been getting better and better. How can this be? The explanation is that we usually hear only one side of the story. We're taught to think only of the negatives of fossil fuels, their risks and side effects, but not their positives.

Since the beginning of human history Mars has been an alluring dream - the stuff of legends, gods, and mystery. The planet most like ours, it has still been thought impossible to reach, let alone explore and inhabit. Now with the advent of a revolutionary new plan, all this has changed. Leading space exploration authority Robert Zubrin has crafted a daring new blueprint, Mars Direct, presented here with engaging anecdotes. The Case for Mars is not a vision for the far future or one that will cost us impossible billions.

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.

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.

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.

The future is here...in an adventure of cosmic dimension. In December, 1999, a multinational team journeys out to the stars, to the most awesome encounter in human history. Who - or what - is out there? In Cosmos, Carl Sagan explained the universe. In Contact, he predicts its future - and our own.

Famed investigative journalist Eric Schlosser digs deep to uncover secrets about the management of America's nuclear arsenal. A groundbreaking account of accidents, near misses, extraordinary heroism, and technological breakthroughs, Command and Control explores the dilemma that has existed since the dawn of the nuclear age: How do you deploy weapons of mass destruction without being destroyed by them? That question has never been resolved - and Schlosser reveals how the combination of human fallibility and technological complexity still poses a grave risk to mankind.