When the Earth Had Two Moons

When the Earth Had Two Moons

Author: Erik Asphaug

Publisher: HarperCollins

Published: 2019-10-29

Total Pages: 424

ISBN-13: 0062657941

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An astonishing exploration of planet formation and the origins of life by one of the world’s most innovative planetary geologists. In 1959, the Soviet probe Luna 3 took the first photos of the far side of the moon. Even in their poor resolution, the images stunned scientists: the far side is an enormous mountainous expanse, not the vast lava-plains seen from Earth. Subsequent missions have confirmed this in much greater detail. How could this be, and what might it tell us about our own place in the universe? As it turns out, quite a lot. Fourteen billion years ago, the universe exploded into being, creating galaxies and stars. Planets formed out of the leftover dust and gas that coalesced into larger and larger bodies orbiting around each star. In a sort of heavenly survival of the fittest, planetary bodies smashed into each other until solar systems emerged. Curiously, instead of being relatively similar in terms of composition, the planets in our solar system, and the comets, asteroids, satellites and rings, are bewitchingly distinct. So, too, the halves of our moon. In When the Earth Had Two Moons, esteemed planetary geologist Erik Asphaug takes us on an exhilarating tour through the farthest reaches of time and our galaxy to find out why. Beautifully written and provocatively argued, When the Earth Had Two Moons is not only a mind-blowing astronomical tour but a profound inquiry into the nature of life here—and billions of miles from home.


What If the Earth Had Two Moons?

What If the Earth Had Two Moons?

Author: Neil F. Comins

Publisher: Macmillan

Published: 2010-03-30

Total Pages: 506

ISBN-13: 142995793X

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"What if?" questions stimulate people to think in new ways, to refresh old ideas, and to make new discoveries. 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 alike, this book is a fascinating journey through physics and astronomy, and follows on the author's previous bestseller, What if the Moon Didn't Exist?, with completely new scenarios backed by the latest astronomical research.


What If the Moon Didn't Exist?

What If the Moon Didn't Exist?

Author: Neil F. Comins

Publisher:

Published: 2012-09

Total Pages: 0

ISBN-13: 9781475930948

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Demonstrates how ten hypothetical situations would affect our planet and life on it. Topics include: what if the moon didn't exist, what if earth were tilted like Uranus, what if a black hole passed through earth, and so on.


The Two Moons

The Two Moons

Author: James P. Hogan

Publisher: Baen Books

Published: 2006

Total Pages: 307

ISBN-13: 1416509364

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Previously published by Del Rey Books as two separate novels--"Inherit the Stars" and "The Gentle Giants of Ganymede"--these two stories, now available in one volume, began Hogan's legendary Giants series and the career of a major SF talent.


Many Skies

Many Skies

Author: Arthur Upgren

Publisher: Rutgers University Press

Published: 2005-01-18

Total Pages: 212

ISBN-13: 0813553563

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What if Earth had several moons or massive rings like Saturn? What if the Sun were but one star in a double-star or triple-star system? What if Earth were the only planet circling the Sun? These and other imaginative scenarios are the subject of Arthur Upgren's inventive book Many Skies: Alternative Histories of the Sun, Moon, Planets, and Stars. Although the night sky as we know it seems eternal and inevitable, Upgren reminds us that, just as easily, it could have been very different. Had the solar sytem happened to be in the midst of a star cluster, we might have many more bright stars in the sky. Yet had it been located beyond the edge of the Milky Way galaxy, we might have no stars at all. If Venus or Mars had a moon as large as ours, we would be able to view it easily with the unaided eye. Given these or other alternative skies, what might Ptolemy or Copernicus have concluded about the center of the solar sytem and the Sun? This book not only examines the changes in science that these alternative solar, stellar, and galactic arrangements would have brought, it also explores the different theologies, astrologies, and methods of tracking time that would have developed to reflect them. Our perception of our surroundings, the number of gods we worship, the symbols we use in art and literature, even the way we form nations and empires are all closely tied to our particular (and accidental) placement in the universe. Many Skies, however, is not merely a fanciful play on what might have been. Upgren also explores the actual ways that human interferences such as light pollution are changing the night sky. Our atmosphere, he warns, will appear very different if we have belt of debris circling the globe and blotting out the stars, as will happen if advertisers one day pollute space with brilliant satellites displaying their products. From fanciful to foreboding, the scenarios in Many Skies will both delight and inspire reflection, reminding us that ours is but one of many worldviews based on our experience of a universe that is as much a product of accident as it is of intention.


Moons

Moons

Author: David A. Rothery

Publisher: Oxford University Press, USA

Published: 2015

Total Pages: 177

ISBN-13: 0198735278

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Our Solar System contains more moons than planets. They show astonishing variety, and some look more likely than Mars to host microbial life. David Rothery describes these fascinating small worlds, their discovery, names, and what they can tell us about our solar system.


Walk Two Moons

Walk Two Moons

Author: Sharon Creech

Publisher: Harper Collins

Published: 2009-10-06

Total Pages: 292

ISBN-13: 0061972517

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In her own singularly beautiful style, Newbery Medal winner Sharon Creech intricately weaves together two tales, one funny, one bittersweet, to create a heartwarming, compelling, and utterly moving story of love, loss, and the complexity of human emotion. Thirteen-year-old Salamanca Tree Hiddle, proud of her country roots and the "Indian-ness in her blood," travels from Ohio to Idaho with her eccentric grandparents. Along the way, she tells them of the story of Phoebe Winterbottom, who received mysterious messages, who met a "potential lunatic," and whose mother disappeared. As Sal entertains her grandparents with Phoebe's outrageous story, her own story begins to unfold—the story of a thirteen-year-old girl whose only wish is to be reunited with her missing mother.


Origins of the Earth, Moon, and Life

Origins of the Earth, Moon, and Life

Author: Akio Makishima

Publisher: Elsevier

Published: 2017-01-27

Total Pages: 270

ISBN-13: 0128120592

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Origins of the Earth, Moon, and Life: An Interdisciplinary Approach presents state-of-the-art knowledge that is based on theories, experiments, observations, calculations, and analytical data from five astro-sciences, astronomy, astrobiology, astrogeology, astrophysics, and cosmochemistry. Beginning with the origin of elements, and moving on to cover the formation of the early Solar System, the giant impact model of the Earth and Moon, the oldest records of life, and the possibility of life on other planets in the Solar System, this interdisciplinary reference provides a complex understanding of the planets and the formation of life. Synthesizing concepts from all branches of astro-sciences into one, the book is a valuable reference for researchers in astrogeology, astrophysics, cosmochemistry, astrobiology, astronomy, and other space science fields, helping users better understand the intersection of these sciences. Includes extensive figures and tables to enhance key concepts Uses callout boxes throughout to provide context and deeper explanations Presents up-to-date information on the universe, stars, planets, moons, and life in the solar system Combines knowledge from the fields of astrogeology, astrophysics, cosmochemistry, astrobiology, and astronomy, helping readers understand the origins of the Earth, the moon, and life in our solar system