In What If the Earth Had Two Moons, Neil Comins leads us on a fascinating ten-world journey as we explore what our planet would be like under alternative astronomical conditions. In each case, the Earth would be different, often in surprising ways. The title chapter, for example, gives us a second moon orbiting closer to Earth than the one we have now. The night sky is a lot brighter, but that won't last forever. Eventually the moons collide, with one extra-massive moon emerging after a period during which Earth sports a Saturn-like ring. This and nine and other speculative essays provide us with insights into the Earth as it exists today, while shedding new light on the burgeoning search for life on planets orbiting other stars. Appealing to adult and young adult readers alike, this book follows on the author's previous bestseller, What If the Moon Didn't Exist?, with completely new scenarios backed by the latest astronomical research.

    In the 14 billion years since, scientists have pointed their telescopes upward, peering outward in space and backward in time, developing and refining theories to explain the weird and wonderful phenomena they observed.Through these observations, we now understand concepts like the size of the universe (still expanding), the distance to the next-nearest star from earth (Alpha Centauri, 26 trillion miles) and what drives the formation of elements (nuclear fusion), planets and galaxies (gravity), and black holes (gravitational collapse). But are these cosmological questions definitively answered or is there more to discover?Oxford University astrophysicist and popular YouTube personality Dr. Becky Smethurst presents everything you need to know about the universe in 10 accessible and engaging lessons.In Space at the Speed of Light: The History of 14 Billion Years for People Short on Time, she guides you through fundamental questions, both answered and unanswered, posed by space scientists. Why does gravity matter? How do we know the big bang happened? What is dark matter? Do aliens exist? Why is the sky dark at night? If you have ever looked up at night and wondered how it all works, you will find answers - and many more questions - in this pocket-sized tour of the universe!

    This discovery dramatically reshaped how humans understood their place in the cosmos, and once and for all laid to rest the idea that the Milky Way galaxy was alone in the universe. Six years later, continuing research by Hubble and others forced Albert Einstein to renounce his own cosmic model and finally accept the astonishing fact that the universe was not immobile but instead expanding. The fascinating story of these interwoven discoveries includes battles of will, clever insights, and wrong turns made by the early investigators in this great twentieth-century pursuit. It is a story of science in the making that shows how these discoveries were not the work of a lone genius but the combined efforts of many talented scientists and researchers toiling away behind the scenes. The intriguing characters include Henrietta Leavitt, who discovered the means to measure the vast dimensions of the cosmos . . . Vesto Slipher, the first and unheralded discoverer of the universe’s expansion . . . Georges Lemaître, the Jesuit priest who correctly interpreted Einstein’s theories in relation to the universe . . . Milton Humason, who, with only an eighth-grade education, became a world-renowned expert on galaxy motions . . . and Harlow Shapley, Hubble’s nemesis, whose flawed vision of the universe delayed the discovery of its true nature and startling size for more than a decade.Here is a watershed moment in the history of astronomy, brought about by the exceptional combination of human curiosity, intelligence, and enterprise, and vividly told by acclaimed science writer Marcia Bartusiak.

    Their work has uncovered a number of the universe’s more surprising secrets, and many believe further wonders remain hidden within the theory’s tangle of equations, waiting to be exposed. In this sweeping narrative of science and culture, astrophysicist Pedro Ferreira brings general relativity to life through the story of the brilliant physicists, mathematicians, and astronomers who have taken up its challenge. For these scientists, the theory has been both a treasure trove and an enigma, fueling a century of intellectual struggle and triumph.. Einstein’s theory, which explains the relationships among gravity, space, and time, is possibly the most perfect intellectual achievement of modern physics, yet studying it has always been a controversial endeavor. Relativists were the target of persecution in Hitler’s Germany, hounded in Stalin’s Russia, and disdained in 1950s America. Even today, PhD students are warned that specializing in general relativity will make them unemployable. Despite these pitfalls, general relativity has flourished, delivering key insights into our understanding of the origin of time and the evolution of all the stars and galaxies in the cosmos. Its adherents have revealed what lies at the farthest reaches of the universe, shed light on the smallest scales of existence, and explained how the fabric of reality emerges. Dark matter, dark energy, black holes, and string theory are all progeny of Einstein’s theory. We are in the midst of a momentous transformation in modern physics. As scientists look farther and more clearly into space than ever before, The Perfect Theory reveals the greater relevance of general relativity, showing us where it started, where it has led, and where it can still take us.

    The universe is all about extremes, and in this engaging and thought-provoking book, astronomer Bryan Gaensler gives a whirlwind tour of the galaxies, with an emphasis on its fastest, hottest, heaviest, brightest, oldest, densest, and even loudest elements. From supernova explosions a billion times brighter than the sun to an asteroid the size of a beach ball, Extreme Cosmos offers a fascinating, fresh, and informed perspective of the remarkable richness of the universe, and the incredible physics that modern astronomy has revealed.

      In the constellation of Eridanus, there lurks a cosmic mystery: It’s as if something has taken a huge bite out of the universe. But what is the culprit? The hole in the universe is just one of many puzzles keeping cosmologists busy. Supermassive black holes, bubbles of nothingness gobbling up space, monster universes swallowing others—these and many other bizarre ideas are being pursued by scientists. Due to breathtaking progress in astronomy, the history of our universe is now better understood than the history of our own planet. But these advances have uncovered some startling riddles. In this electrifying new book, renowned cosmologist and author Paul Davies lucidly explains what we know about the cosmos and its enigmas, exploring the tantalizing—and sometimes terrifying—possibilities that lie before us. As Davies guides us through the audacious research offering mind-bending solutions to these and other mysteries, he leads us up to the greatest outstanding conundrum of all: Why does the universe even exist in the first place? And how did a system of mindless, purposeless particles manage to bring forth conscious, thinking beings? Filled with wit and wonder, What’s Eating the Universe? is a dazzling tour of cosmic questions, sure to entertain, enchant, and inspire us all.

    Einstein predicted these tiny ripples in the fabric of spacetime nearly a hundred years ago, but they were never perceived directly until now. Decades in the making, this momentous discovery has given scientists a new understanding of the cataclysmic events that shape the universe and a new confirmation of Einstein's theory of general relativity. Ripples in Spacetime is an engaging account of the international effort to complete Einstein's project, capture his elusive ripples, and launch an era of gravitational-wave astronomy that promises to explain, more vividly than ever before, our universe's structure and origin.The quest for gravitational waves involved years of risky research and many personal and professional struggles that threatened to derail one of the world's largest scientific endeavors. Govert Schilling takes readers to sites where these stories unfolded--including Japan's KAGRA detector, Chile's Atacama Cosmology Telescope, the South Pole's BICEP detectors, and the United States' LIGO labs. He explains the seeming impossibility of developing technologies sensitive enough to detect waves from two colliding black holes in the very distant universe, and describes the astounding precision of the LIGO detectors. Along the way Schilling clarifies concepts such as general relativity, neutron stars, and the big bang using language that readers with little scientific background can grasp.Ripples in Spacetime provides a window into the next frontiers of astronomy, weaving far-reaching predictions and discoveries into a gripping story of human ambition and perseverance.

    Every massive star leaves behind a black hole when it dies, and every galaxy harbors a supermassive black hole at its center. Frighteningly enigmatic, these dark giants continue to astound even the scientists who spend their careers studying them. Which came first, the galaxy or its central black hole? What happens if you travel into one—instant death or something weirder? And, perhaps most important, how can we ever know anything for sure about black holes when they destroy information by their very nature?In Einstein’s Monsters, distinguished astronomer Chris Impey takes readers on an exploration of these and other questions at the cutting edge of astrophysics, as well as the history of black holes’ role in theoretical physics—from confirming Einstein’s equations for general relativity to testing string theory. He blends this history with a poignant account of the phenomena scientists have witnessed while observing black holes: stars swarming like bees around the center of our galaxy; black holes performing gravitational waltzes with visible stars; the cymbal clash of two black holes colliding, releasing ripples in space-time.Clear, compelling, and profound, Einstein’s Monsters reveals how our comprehension of black holes is intrinsically linked to how we make sense of the universe and our place within it. From the small questions to the big ones—from the tiniest particles to the nature of space-time itself—black holes might be the key to a deeper understanding of the cosmos.

    Authoritative and engaging, Paul Parsons takes us on a rollercoaster ride through billions of light years to tell the story of the Big Bang, from birth to death.13.8 billion years ago, something incredible happened. Matter, energy, space and time all suddenly burst into existence in a cataclysmic event that’s come to be known as the Big Bang. It was the birth of our universe. What started life smaller than the tiniest subatomic particle is now unimaginably vast and plays home to trillions of galaxies. The formulation of the Big Bang theory is a story that combines some of the most far-reaching concepts in fundamental physics with equally profound observations of the cosmos.From our realization that we are on a planet orbiting a star in one of many galaxies, to the discovery that our universe is expanding, to the groundbreaking theories of Einstein that laid the groundwork for the Big Bang cosmology of today – as each new discovery deepens our understanding of the origins of our universe, a clearer picture is forming of how it will all end. Will we ultimately burn out or fade away? Could the end simply signal a new beginning, as the universe rebounds into a fresh expanding phase? And was our Big Bang just one of many, making our cosmos only a small part of a sprawling multiverse of parallel universes?

    Often billions of times more massive than the Sun, they lurk in the inner sanctum of almost every galaxy of stars in the universe. They're mysterious chasms so destructive and unforgiving that not even light can escape their deadly wrath.Recent research, however, has led to a cascade of new discoveries that have revealed an entirely different side to black holes. As the astrophysicist Caleb Scharf reveals in Gravity's Engines, these chasms in space-time don't just vacuum up everything that comes near them; they also spit out huge beams and clouds of matter. Black holes blow bubbles.With clarity and keen intellect, Scharf masterfully explains how these bubbles profoundly rearrange the cosmos around them. Engaging with our deepest questions about the universe, he takes us on an intimate journey through the endlessly colorful place we call our galaxy and reminds us that the Milky Way sits in a special place in the cosmic zoo—a "sweet spot" of properties. Is it coincidental that we find ourselves here at this place and time? Could there be a deeper connection between the nature of black holes and their role in the universe and the phenomenon of life? We are, after all, made of the stuff of stars.

    Taking in 440 sextillion kilometres of space and 13.8 billion years of time, it is physically impossible to make a better map: we will never see the early universe in more detail. On the one hand, such a view is the apotheosis of modern cosmology, on the other, it threatens to undermine almost everything we hold cosmologically sacrosanct. The map contains anomalies that challenge our understanding of the universe. It will force us to revisit what is known and what is unknown, to construct a new model of our universe. This is the first book to address what will be an epoch-defining scientific paradigm shift. Stuart Clark will ask if Newton's famous laws of gravity need to be rewritten; if dark matter and dark energy are just celestial phantoms? Can we ever know what happened before the Big Bang? What’s at the bottom of a black hole? Are there universes beyond our own? Does time exist? Are the once immutable laws of physics changing?

    Pluto is entrenched in our cultural and emotional view of the cosmos, and Neil deGrasse Tyson, award-winning author and director of the Rose Center, is on a quest to discover why. He stood at the heart of the controversy over Pluto's demotion, and consequently Plutophiles have freely shared their opinions with him, including endless hate mail from third-graders. With his inimitable wit, Tyson delivers a minihistory of planets, describes the oversized characters of the people who study them, and recounts how America's favorite planet was ousted from the cosmic hub.

    Before the decade is out, telltale signs that they harbor life may be found. If they are, the ramifications for all areas of human thought and endeavor--from religion and philosophy to art and biology--will be breathtaking. In Strange New Worlds, renowned astronomer Ray Jayawardhana brings news from the front lines of the epic quest to find planets--and alien life--beyond our solar system.Only in the past fifteen years, after millennia of speculation, have astronomers begun to discover planets around other stars--hundreds in fact. But the hunt to find a true Earth-like world goes on. In this book, Jayawardhana vividly recounts the stories of the scientists and the remarkable breakthroughs that have ushered in this extraordinary age of exploration. He describes the latest findings--including his own--that are challenging our view of the cosmos and casting new light on the origins and evolution of planets and planetary systems. He reveals how technology is rapidly advancing to support direct observations of Jupiter-like gas giants and super-Earths--rocky planets with several times the mass of our own planet--and how astronomers use biomarkers to seek possible life on other worlds.Strange New Worlds provides an insider's look at the cutting-edge science of today's planet hunters, our prospects for discovering alien life, and the debates and controversies at the forefront of extrasolar-planet research.

    Then, in 2005, astronomer Mike Brown made the discovery of a lifetime: a tenth planet, Eris, slightly bigger than Pluto. But instead of its resulting in one more planet being added to our solar system, Brown’s find ignited a firestorm of controversy that riled the usually sedate world of astronomy and launched him into the public eye. The debate culminated in the demotion of Pluto from real planet to the newly coined category of “dwarf” planet. Suddenly Brown was receiving hate mail from schoolchildren and being bombarded by TV reporters—all because of the discovery he had spent years searching for and a lifetime dreaming about.Filled with both humor and drama, How I Killed Pluto and Why It Had It Coming is Mike Brown’s engaging first-person account of the most tumultuous year in modern astronomy—which he inadvertently caused. As it guides readers through important scientific concepts and inspires us to think more deeply about our place in the cosmos, it is also an entertaining and enlightening personal story: While Brown sought to expand our understanding of the vast nature of space, his own life was changed in the most immediate, human ways by love, birth, and death. A heartfelt and personal perspective on the demotion of everyone’s favorite farflung planet, How I Killed Pluto and Why It Had It Coming is the book for anyone, young or old, who has ever dreamed of exploring the universe—and who among us hasn’t?

    Starting once again with fossils, he turns his gaze skyward, showing us how the entirety of the universe’s fourteen-billion-year history can be seen in our bodies. As he moves from our very molecular composition (a result of stellar events at the origin of our solar system) through the workings of our eyes, Shubin makes clear how the evolution of the cosmos has profoundly marked our own bodies. Fully illustrated with black and white drawings.