Böcker av David A. Weintraub

Astronomers have determined that our universe is 13.7 billion years old. How exactly did they come to this precise conclusion? How Old Is the Universe? tells the incredible story of how astronomers solved one of the most compelling mysteries in science and, along the way, introduces readers to fundamental concepts and cutting-edge advances in modern astronomy. The age of our universe poses a deceptively simple question, and its answer carries profound implications for science, religion, and philosophy. David Weintraub traces the centuries-old quest by astronomers to fathom the secrets of the nighttime sky. Describing the achievements of the visionaries whose discoveries collectively unveiled a fundamental mystery, he shows how many independent lines of inquiry and much painstakingly gathered evidence, when fitted together like pieces in a cosmic puzzle, led to the long-sought answer. Astronomers don't believe the universe is 13.7 billion years old--they know it. You will too after reading this book. By focusing on one of the most crucial questions about the universe and challenging readers to understand the answer, Weintraub familiarizes readers with the ideas and phenomena at the heart of modern astronomy, including red giants and white dwarfs, cepheid variable stars and supernovae, clusters of galaxies, gravitational lensing, dark matter, dark energy and the accelerating universe--and much more. Offering a unique historical approach to astronomy, How Old Is the Universe? sheds light on the inner workings of scientific inquiry and reveals how astronomers grapple with deep questions about the physical nature of our universe.

Other religions could be practiced on distant worlds but nevertheless identify both Earth as a place and humankind as a species of singular spiritual religious importance, while some religions could be practiced equally well anywhere in the universe by any sentient beings.

A Note from the Author: On August 24, 2006, at the 26th General Assembly of the International Astronomical Union (IAU) in Prague, by a majority vote of only the 424 members present, the IAU (an organization of over 10,000 members) passed a resolution defining planet in such a way as to exclude Pluto and established a new class of objects in the solar system to be called "e;dwarf planets,"e; which was deliberately designed to include Pluto. With the discovery of Eris (2003 UB313)--an outer solar system object thought to be both slightly larger than Pluto and twice as far from the Sun--astronomers have again been thrown into an age-old debate about what is and what is not a planet. One of many sizeable hunks of rock and ice in the Kuiper Belt, Eris has resisted easy classification and inspired much controversy over the definition of planethood. But, Pluto itself has been subject to controversy since its discovery in 1930, and questions over its status linger. Is it a planet? What exactly is a planet? Is Pluto a Planet? tells the story of how the meaning of the word "e;planet"e; has changed from antiquity to the present day, as new objects in our solar system have been discovered. In lively, thoroughly accessible prose, David Weintraub provides the historical, philosophical, and astronomical background that allows us to decide for ourselves whether Pluto is indeed a planet. The number of possible planets has ranged widely over the centuries, from five to seventeen. This book makes sense of it all--from the ancient Greeks' observation that some stars wander while others don't; to Copernicus, who made Earth a planet but rejected the Sun and the Moon; to the discoveries of comets, Uranus, Ceres, the asteroid belt, Neptune, Pluto, centaurs, the Kuiper Belt and Eris, and extrasolar planets. Weaving the history of our thinking about planets and cosmology into a single, remarkable story, Is Pluto a Planet? is for all those who seek a fuller understanding of the science surrounding both Pluto and the provocative recent discoveries in our outer solar system.