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TIMOTHY F. SLATER

University of Wyoming

ROGER A. FREEDMAN

University of California, Santa Barbara

W.H. Freeman and Company

A Macmillan Higher Education Company

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Publisher: Kate Parker

Acquisitions Editor: Alicia Brady

Development Editors: Blythe Robbins; Kharissia Pettus

Senior Media and Supplements Editor: Amy Thorne

Assistant Editor: Tue Tran

Marketing Manager: Taryn Burns

Marketing Assistant: Samantha Zimbler

Project Editor: Kerry O’Shaughnessy

Production Manager: Julia DeRosa

Cover and Text Designer: Blake Logan

Illustration Coordinator: Janice Donnola

Illustrations: Imagineering

Photo Editors: Sheena Goldstein, Nick Ciani

Photo Researcher: Feldman & Associates

Composition: Northeastern Graphic, Inc.

Printing and Binding: RR Donnelley

Credit is given to the following sources for photos in the Cosmic Connections and Visual Literacy Tasks and on the cover: NASA/SDO/Goddard Space Flight Center; Cosmic Connections and Visual Literacy Tasks: p. 6: Earth: JPL/NASA; Sun: NOAA National Climatic Data Center; starry sky: Space Telescope Science Institute (hubblesite.org); nebula: NASA, ESA, M. Robberto (STScI/ESA) and the Hubble Space Telescope Orion Treasury Project Team; supernova: NASA, ESA, J. Hester and A. Loll (Arizona State University); Milky Way: NASA/JPL-Caltech/R. Hurt (SSC); galaxy clusters: National Optical Astronomy Observatory; observable universe: 2MASS, IPAC/Caltech, and University of Massachusetts; pp. 98–99: NASA/JPL/Space Science Institute; p. 110: NASA/JPL/Space Science Institute; p.154: NASA Jet Propulsion Laboratory; p. 158: NASA Jet Propulsion Laboratory; p. 164: NASA/JPL; p. 177: Earth: NASA; all others: NASA/JPL; p. 208: Sun: SOHO (ESA & NASA); stars: NASA and H. Richer (University of British Columbia); p. 291: Sun: SOHO/MDI (ESA & NASA); p. 319: spiral galaxy: NASA/ESA; globular cluster: S. Fakfa and K. Honeycutt, Indiana University/WIYN/NOAO/NSF; p. 343: colliding galaxies #1: Bob and Bill Twardy/Adam Block/NOAO/AURA/NSF; colliding galaxies #2: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration; colliding galaxies #3: NASA/JPL-Caltech/Z. Wang (Harvard-Smithsonian CfA); colliding galaxies #4: John Dubinski, University of Toronto.

Library of Congress Control Number: 2013956580

ISBN-13: 978-1-4641-4085-3

ISBN-10: 1-4641-4085-5

© 2014, 2012 by W. H. Freeman and Company

All rights reserved

Printed in the United States of America

Third printing

W. H. Freeman and Company

41 Madison Avenue, New York, NY 10010

Houndmills, Basingstoke RG21 6XS, England

www.whfreeman.com

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TIM: To Stephanie Jean Slater, my wife and partner in all things; and to my children, who I hope never stop wondering about what floats beyond Earth

ROGER: To my wife Caroline Robillard, for expanding my universe

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