Acknowledgments, continued from page ii

NASA: Cover image and the background image of the title page of Mars by Elaine Landau are from NASA.

The Perseus Books Group: Cover of ARE WE MOVING TO MARS? by Anne Schraff. Copyright © 1996 by John Muir Publications, a division of The Perseus Books Group. All rights reserved.

Rand McNally & Company: Cover of RAND MCNALLY QUICK REFERENCE WORLD ATLAS copyright © 1995 by Rand McNally & Company. All rights reserved.

Scholastic Library Publishing, Inc.: Mars by Elaine Landau. All rights reserved. Reprinted by permission of Franklin Watts an imprint of Scholastic Library Publishing, Inc.

Time Inc.: Cover of TIME FOR KIDS, September 13, 1996, Vol. 2, No. 1. Copyright © 1996 Time Inc. All rights reserved.

World Almanac Education Group, Inc.: Cover of the WORLD ALMANAC FOR KIDS 2008. Copyright © 2007 World Almanac Education Group. All Rights Reserved. Used by permission.

World Book, Inc.: The World Book Encyclopedia. © 2008. World Book, Inc. By permission of the publisher. www.worldbookonline.com.

Photographs

Cover (tc) argus/Shutterstock. (ml – mr) Tischenko Irina/Shutterstock. DJ Mattaar/Shutterstock. Paul A. Suders/Corbis. Richard Cummins/Corbis. Bill Perry/Shutterstock. Brandon D. Cole/Corbis. 2 (t,c,b) Liz Garza Williams. 4 (c) Liz Garza Williams. (bg) PhotoLink/PhotoDisc/Getty Images. 6 (t) Robert Brenner/PhotoEdit. (ml) Tony Freeman/PhotoEdit. (mc) Merritt Vincent/PhotoEdit. (bl) Michael Newman/PhotoEdit. (bc) A. Ramey/PhotoEdit. (br,mr) David Young-Wolff/PhotoEdit. 7 (t) Paul A. Souders/Corbis. (b) Chris Cheadle/Getty Images. 8–9 (bg) Johnny Stockshooter/Superstock. 10 (t) Eastcott/Momatiuk/WoodFin Camp & Associates. 14–15 (bg) Glowimages/Getty Images. 15 (c) Neil Setchfield/Alamy. 16 (b) Toshifumi Kitamura/AFP/Getty Images. (t) chromepix.com/Alamy. 17 (t) JTB Photo Communications Inc./Alamy. (b) Image Source/Jupiterimages. 19 (c) Ariel Skelley/Getty Images. 20 (c) AP Photo/B. K.Bangash. (b) Ashley Cooper/Alamy. (t) Geray Sweeney/Corbis. 21 (tl) Peter Turnley/Corbis. (tr) Forestier Yves/Corbis SYGMA. (ml) ANSA/Corbis. (mr) Getty Images. (bl) Dale Spartas/Corbis. 22–23 (bg) Geray Sweeney/Corbis. 24 (b) Cultura/Alamy. 25 (t) S. Brookes Webb/Solent News Agency/Corbis SYGMA. (b) Photonews/Corbis. 26 (t) Galen Rowell/Mountain Light/Alamy. (c) Peter Turnley/Corbis. (b) Getty Images. 27 (t) DK Limited/Corbis. (br) Dale Spartas/Corbis. (br) Ashley Cooper/Corbis. 28–29 (bg) Dario Mitidieri/Getty Images. 31 (bc) SW Productions/BrandX/Corbis. (br) David Toase/Getty Images. 36 (bg) Chris Birck. (r) Mark Richards/PhotoEdit. 38 (t, bg) Liz Garza-Williams. 39 (b) Liz Garza-Williams. 40 (l) Sandro Miller/Getty Images. (c) Wally McNamee/Corbis. (r) Tony Freeman/PhotoEdit. 41 (t, bl) Bettmann/Corbis. (br) Flip Schulke/Corbis. 42–43 (bg) Bettmann/Corbis. 44 (t) Owen Franken/Corbis. 46 (ml) Siede Preis/PhotoDisc/Getty Images. (bl) Stockbyte/Getty Images. (tml) Larry West/Getty Images. (mc) Jess Alford/PhotoDisc/Getty Images. (bml) Liz Garza-Williams. (tmr) Ryan McVay/PhotoDisc/Getty Images. (mr) Fransisco Erize/Bruce Coleman. (bmr) Jules Frazier/PhotoDisc/Getty Images. (br) Paul Dance/Getty Images. 48 (l) Jess Alford/PhotoDisc/Getty Images. 48–49 (bg) Images.com/Corbis. 49 (c) courtesy of Free The Children. 50 (ml, bl) courtesy of the Halilbegovich and Morrison families/Kids Can Press. 51 (tr,tmr) Hafsat Abiola. (mr, br) courtesy of Free The Children. 53 (bg) Digital Stock. 54 (t) Culver Pictures Inc. (c) Bettman/Corbis. (b) Library of Congress Prints and Photographs Division. 55 (ml, bl) Hulton-Deutsch Collection/Corbis. (tl) Wally McNamee/Corbis. (mr) Tony Freeman/PhotoEdit. (tr) Flip Schulke/Corbis. 56–57 (bg) Culver Pictures Inc. 58 (l) Bettman/Corbis. 58–59 (bg) Associated Press. 60 (t, b) Bettman/Corbis. 61 (b) Hulton-Deutsch Collection/Corbis. 62 (b) Bettman/Corbis. (t) Library of Congress. 63 (c) Bettman/Corbis. 65 Tim Pannell/Corbis. 66 (m) Somos Images/Corbis. 70 (tc) Frank Krahmer/Bruce Coleman. (tr, c) Tom Brakefield/Bruce Coleman. (mr) Rod Williams/Bruce Coleman. (br) Tom Walker/Getty Images. (bc) Frank Krahmer/Bruce Coleman. (bl) John Giustina/Bruce Coleman. (ml) Joe McDonald/Bruce Coleman. (tl) Bradley Simmons/Bruce Coleman. (bg) Digital Stock. 71 (tl) Digital Stock. 72 (t, tr, bmr, bl, ml, tml) Digital Stock. (tmr, tl) PhotoDisc/Getty Images. (br) Gabe Palmer/Corbis. 74 (l,r) Liz Garza-Williams. 75 (t) Liz Garza-Williams. (left inset-bg) Art Wolfe/Getty Images. (left inset-l) Zig Leszczynski/AnimalsAnimals. (left inset-mc) Jeff Foott/Bruce Coleman. (left inset-br) Tom Brakefield/Bruce Coleman. (left inset-tr) Corel Predators. (right inset-c) John Shaw/Bruce Coleman. (right inset-tl, bl) Tom Brakefield/Bruce Coleman. (right inset-mc) Rodger Wilmshurst/Bruce Coleman. (right inset-br) John Shaw/Bruce Coleman. (right inset-bg) PhotoDisc/Getty Images Colors - SS1. 76–77 (bg) Craig Tuttle/Corbis. 78 (t) Rob Stapleton/AP Photo. 80 (tl) Brian Hagiwara/Jupiterimages. (ml, tc) Barbara Penovar/PhotoDisc/Getty Images. (bl, bc) PhotoDisc/Getty Images. (mc) Steven Hunt/Getty Images. (tr) Ryan McVay/PhotoDisc/Getty Images. (mr) Walter Hodges/Getty Images. (br) Artville. 82 (l) Ryan McVay/PhotoDisc/Getty Images. 82–83 (bg) Discovery Channel Images/Getty Images. 84 (br) Ed Gifford/Masterfile. (tl) Joe McDonald/Animals Animals. (bl) Gary Griffen/Animals Animals. (tl) Sumio Harada/Minden Pictures. 85 (b) Corbis. (t) Charles Volkland/age fotostock/SuperStock. 87 (c) Bob & Clara Calhoun. 88 (b) PhotoDisc/Getty Images. (tr) Roy Toft/National Geographic/Getty Images. (c) Johnny Johnson/Getty Images. 89 (tl) Michael Breuer/SuperStock. (tr) Corbis. (ml) Dex Image/Getty Images. (mr) Holt Studios International Ltd/Alamy. (bl) Tom Walker/The Image Bank/Getty Images. 90–91 (bg) Roy Toft/National Geographic/Getty Images. 92 (c) Dex Image/Getty Images. (bl) PhotoDisc/Getty Images. 93 (t) Daniel Cardiff/iStockphoto. (r) William Weber/Visuals Unlimited. (b) Corbis. 94 (bg) Tom Walker/The Image Bank/Getty Images. 95 (tl) Corbis. (tr) Raymond Gehman/National Geographic Image Collection. (tmr) Comstock Images/Jupiterimages. (mr) PhotoDisc/Getty Images. (ml) Martin Ruegner/Getty Images. (bml) Mike Dobel/Alamy. (bc) Radius Images/Alamy. (bl) PhotoAlto/Alamy. 96 (bg) Johnny Johnson/Getty Images. 97 (bg) Robert McGouey/Alamy. 99 (m) Jeff Foott/Getty Images. 101 (tr) Yva Momatiuk/John Eastcott/Getty Images. 103 (tr) franzfoto/Alamy. 104 (ml, mc, br) Liz Garza-Williams. (bg) courtesy of National Archives. 106 (tr) Bettmann/Corbis. (c) Ron Burton/Liaison Agency/Getty Images. (mr) courtesy of National Archives. (br) Corbis. (bl) Key Color/Index Stock Imagery. 107 (tl) Anne Frank Fonds-Basel/Anne Frank House/Getty Images. (tr) Lee & Low Books. (tc) Bettmann/Corbis. 108 (t,l) Bettmann/Corbis. (r) Moorland Spingarn Research Library. (b) Joe Rosenthal/Corbis. 109 (t, b) Bettmann/Corbis. (r) Hulton Archive/Getty Images. 110 (t) Hulton Archive/Getty Images. 111 (t) courtesy of National Archives. 112–113 (bg) Corbis. 114 (t) Bettmann/Corbis. 116 (bl) PhotoDisc/Getty images. (bc) M. Dillon/Corbis. (br) Paul Thomas/Getty Images Inc. (tr) Anthony Redpath/Corbis. (tc, bmr) George B. Diebold/Corbis. (mr) Image100/Corbis. (c) Paul Barton/Corbis. (ml) Don Mason/Corbis. 118 (l) Cydney Conger/Corbis. (c) PhotoDisc/Getty Images. 118–119 (bg) Comstock/Corbis. 120 (tl) Bob Rowan/Progressive Image/Corbis. (ml) Dave Bartruff/Corbis. (bl) Stan Fellerman/Corbis. 120–121 (bg) Comstock/Corbis. 121 (b) Anthony Dunn/Alamy. (c) Romeo Gacad/AFP/Getty Images. (t) Steven May/Alamy. 123 (tl) U.S. Senate Photo Studio. (ml) Dennis Brack/stockphoto.com. (tc) Hulton-Deutsch Collection/Corbis. (mc) Corbis. (tr) Paul J. Richards/AFP/Getty Images. 124 (b) William Manning/Corbis. (inset) Pete Saloutos/Corbis. (t) Valdpans/Panoramic Images. 125 (tl) David Crausby/Alamy. (tr) Galen Rowell/Corbis. (ml) Paul Conklin/PhotoEdit. (mr) Jeff Cadge/Getty Images. 126–127 (b) Pete Saloutos/Corbis. 127 (bg) Valdpans/Panoramic Images. 128 (b) Galen Rowell/Corbis. 129 (bg) William Manning/Corbis. 130 (b) Paul Conklin/PhotoEdit. (tl, tmr) Library of Congress. (tr) Lauren Victoria Burke/AP Photo. (tl) Gerald Herbert/AP Photo. 131 (bg) Ron Sachs/Corbis Sygma. 132 (bg) Paul Conklin/PhotoEdit. (mr) Brooks Kraft/Corbis. 133 (b) Michael Ventura. 135 (m) Bob Masters Classic Car Images/Alamy. (b) Car Culture/Getty Images. 140 (bg) Dean Conger/Corbis. 143 (mr) Liz Garza-Williams. 146–147 (bg) China Span/Getty Images. 148 (t) Jose Galvez/PhotoEdit. 150 (l) Artville. (ml) Barbara Penovar/PhotoDisc/Getty Images. (tml) David Young-Wolff/PhotoEdit. (mc, bml) C Squared Studios/PhotoDisc/Getty Images. (mr) EyeWire Inc. (r) Stockbyte. (bmr) Rita Maas/Getty Images. (br) PhotoDisc/Getty Images. (bl) Ron Chapple/Thinkstock Images/Jupiterimages. 152 (l) Thinkstock Images/Jupiter Images. 158 (inset) Charles O’Rear/Corbis. 159 (bl) Image Farm Inc./Alamy. 160 (t) Charles O’Rear/Corbis. 164 (b) Image Farm Inc./Alamy. 167 (l) Joseph Sohm/Corbis. 169 (br) Ron Chapple/Thinkstock Images/Jupiter Images. 174 (br) Karl Weatherly/PhotoDisc/Getty Images. (c) Erik Aeder/SuperStock. 176 (mr) Liz Garza-Williams. 177 (tl, bl, bc) Liz Garza-Williams. (bc) Tony Freeman/PhotoEdit. (br) Mark Richards/PhotoEdit. 178 (tl) Myrleen Cate/PhotoEdit. (ml) Robert W. Ginn/PhotoEdit. (mr) Liz Garza-Williams. (mr) Reuters/Corbis. 179 (tl) Liz Garza-Williams. 180–181 (bg) 3D4Medical.com/Getty Images. 182 (tr) Jeff Schultz/Alaska Stock. 184 (ml, mr, bl, c, bml) Liz Garza-Williams. (tl, t, tml, tr, tmr, ml) PhotoDisc/Getty Images. (l, ml, mr, bmr) Artville. 186 (l) PhotoDisc/Getty Images. (t) Lon C. Diehl/PhotoEdit. 186–187 (bg) Wetzel and Co. (bg) AP Photo/Steven Senne. 187 (tr) S. Wanke/PhotoLink/Getty Images. 188 (br) AP Photo/The Missoulian, Michael Gallacher. (c) Bob Daemmrich/The Image Works. (t) Lon C. Diehl/PhotoEdit. 189 (ml) AP Photo/Stuart Ramson/Special Olympics. (b) AP Photo/Javier Galeano. (mr) Richard Hutchings/PhotoEdit. (tl) Bob Daemmrich/The Image Works. 191 (tr) Used with permission AAGPBL Players Association, Inc. (ml) courtesy of the Northern Indiana Center for History. (bl) Dennis MacDonald/age fotostock. (br) Bettmann/Corbis. 192 (t,c) Rick Burnham/Icon Sports Media Inc./Corbis. (b) Mike Powell/Getty Images. 193 (tl) Wally NcNamee/Corbis. (tr) Duomo/Corbis. (ml) AP Photo/Todd Bissonette. (mr) Mike Powell/Getty Images. (bl) Andy Mead/Icon SMI/Corbis. (bml) Joeleen Pryhitko/Design Pics/Corbis. 194–195 (bg) Rick Burnham/Icon Sports Media Inc./Corbis. 196 (l) AP Photo/David Longstreath. 196–197 (r) Bob Thomas/Getty