The Cosmic Perspective (8th Edition)

Book Preface

We humans have gazed into the sky for countless generations. We have wondered how our lives are connected to the Sun, Moon, planets, and stars that adorn the heavens. Today, through the science of astronomy, we know that these connections go far deeper than our ancestors ever imagined. This book tells the story of modern astronomy and the new perspective, The Cosmic Perspective, that astronomy gives us of ourselves and our planet.

This book grew out of our experience teaching astronomy to both college students and the general public over more than 30 years. During this time, a flood of new discoveries fueled a revolution in our understanding of the cosmos but had little impact on the basic organization and approach of most astronomy textbooks. We felt the time had come to rethink how to organize and teach the major concepts in astronomy to reflect this revolution in scientific understanding. This book is the result.

Who Is This Book For?

The Cosmic Perspective is designed as a textbook for college courses in introductory astronomy, but is suitable for anyone who is curious about the universe. We assume no prior knowledge of astronomy or physics, and the book is especially suited to students who do not intend to major in mathematics or science.

The Cosmic Perspective provides a comprehensive survey of modern astronomy, and it contains enough
material for a two-semester introductory astronomy sequence. It may also be used for one-semester survey courses if professors choose their areas of emphasis. However, instructors of one-term courses may also wish to consider our two shorter versions of this book: The
Essential Cosmic Perspective, which covers a smaller set of topics and is tailored to meet the needs of comprehensive one-semester survey courses in astronomy, and The Cosmic Perspective Fundamentals, which covers only the most fundamental topics in astronomy and is designed for courses that address a more limited set of topics.

New to This Edition

The underlying philosophy, goals, and structure of The Cosmic Perspective remain the same as in past editions, but we have thoroughly updated the text and made a number of other improvements. Here, briefly, is a list of the significant changes you’ll find in the eighth edition:
â–  Major Chapter-Level Changes: We have made numerous significant changes to both update the science and improve the pedagogical flow in this edition. The full list is too long to put here, but major changes include the following:
â–  In Chapter 2, we have made a number of small changes to make sure the discussion works for students in the Southern Hemisphere in addition to working for those in the Northern Hemisphere.
â–  In Chapter 3, we have enhanced the discussion of the nature of science with the new Table 3.2, which summarizes how the same terms often have different meanings in science than in everyday usage.
â–  Chapters 9 and 10 have been significantly rewritten to reflect new results from MESSENGER at Mercury, Curiosity and MAVEN at Mars, and the latest data on global warming.
â–  Chapter 12 has been significantly reorganized and rewritten to reflect recent developments in the study of small bodies, particularly the revolutionary new views provided by recent spacecraft including Dawn, Rosetta, and New Horizons.
â–  Chapter 13 has been heavily revised in light of thousands of new discoveries of extrasolar planets since the prior edition.
â–  In Chapter 14, we have updated the discussion of solar neutrinos and reorganized Section 14.3 into two (rather than the former three) learning goals.
â–  In Chapter 18, we have almost completely rewritten Section 18.4 to focus on events in which black holes can form and neutron stars merge.
â–  Chapter 19 has been revised to reduce jargon and to include a new full-page figure showing the Milky Way in different wavelengths. In addition, Section 19.4 on the galactic center has been rewritten and features a new two-page Cosmic Context spread.
â–  Chapters 20 and 21 have been significantly revised in light of new research into galactic evolution, some of which is based on the work of two of the authors of this book (Donahue and Voit).
â–  Chapter 23 has been updated to reflect the latest results about dark energy and the expansion of the universe.
â–  Chapter 24 has been significantly rewritten, particularly Sections 24.2 and 24.3 (which has also been completely reorganized), thanks to new understanding of the potential habitability of Mars, Titan, and extrasolar planets.
â–  Fully Updated Science: Astronomy is a fast-moving field, and numerous new developments have occurred since the prior edition was published. In addition to the major chapter-level changes above, other scientific updates in this edition include

â–  New results and images from spacecraft exploring our solar system, including Curiosity and MAVEN at Mars, Cassini at Saturn, MESSENGER at Mercury, Dawn at Ceres, New Horizons at Pluto, and more
â–  Recent results from major space observatories, including Hubble and Kepler, and from powerful ground-based observatories such as ALMA
â–  Updated data and models on topics including the formation of planetary systems, global warming, and galaxy formation and evolution
â–  Major new discoveries and statistics relating to the study of extrasolar planets, new research on the timing and possible origin of life on Earth, and much more
■ New Feature — Extraordinary Claims boxes: Carl Sagan made famous the statement “extraordinary claims require extraordinary evidence.” With this new feature, we provide students with examples of extraordinary claims about the universe and how they were either
supported or debunked as scientists collected more evidence. The first of these features appears in Chapter 3, where the context of Sagan’s dictum is also explained. Another nine Extraordinary Claims boxes are sprinkled throughout the rest of the text.
■ New Content in MasteringAstronomy®: The Cosmic Perspective is no longer just a textbook; rather, it is a “learning package” that combines a printed book with deeply integrated, interactive media developed to support every chapter of our book. For students, the MasteringAstronomy Study Area provides a wealth of tutorials and activities to build understanding, while quizzes and exercises allow them to test what they’ve learned. For instructors, the MasteringAstronomy Item Library provides the unprecedented ability to quickly build, post, and automatically grade pre- and post-lecture diagnostic tests, weekly homework assignments, and exams of appropriate difficulty, duration, and content coverage. It also provides the ability to record detailed information on the step-by-step work of every student directly into a powerful and easyto- use gradebook, and to evaluate results with a sophisticated suite of diagnostics. Among the changes you’ll find to the MasteringAstronomy site for this edition are numerous new and revised interactive figures, including many narrated video tours; numerous new tutorials in the Item Library; and a fully updated set of reading, concept, and visual quizzes in both the Study Area and the Item Library.