title: Planets, Stars, and Galaxies: A Visual Encyclopedia of Our Universe
author:  David A. Aguilar 
description: This text introduces readers to the most current information availableabout the universe. Information is presented in a clear and easy-to-understand manner. The author writes in a conversational tone and begins with an introduction to the universe that includes how it began and how we know what we know. Readers are then taken on a virtual tour of the solar system and presented with information about the newly designated 11 planets and their varying categories. Fact boxes are provided for each of the planets with such information as the planets mass, density, length of day and length of year (measured in Earth days), average surface temperature, and more. Comets, the Kuiper Belt, and asteroids are also discussed. This is followed by information on the stars and galaxies. The final two chapters address whether we are alone in the universe and where science and research might take us in the future. The book features bright, eye-catching illustrations that author Aguilar created on his computer.In addition, there are many vibrant photographs in the book that were taken by cameras here on Earth as well as by satellites and telescopes. The layout features colorful, well-annotated images on every page spread. The images nicely supplement the text and help to relay concepts. In one of the chapters, images with a binocular symbol indicate objects that can be seen in the night sky with binoculars. The book concludes with four different time lines; Time Line of the Solar System,Time Line of Humans on Earth, Time Line of Astronomy to 1961,and Time Line of Astronomy 1963 to the Present, which covers through 2020, when spacecraft in the Constellation program are scheduled to return human explorers to the moon. Also included are a glossary, an index, anda list of additional reading and Web sites. With appeal forstudents doing research, as well as the lay reader,this colorful resource is recommended for upper-elementary, middle-school, high-school, and public libraries. Grades 5-12. --Maren Ostergard
zlib_text: ![](Images/image00137.jpeg)
  
  Bright exploding stars like the one here, shining below the disk galaxy,
  helped astrophysicists determine that the universe is expanding faster than we
  expected.
  
  ![](Images/image00147.jpeg)
  
  ![](Images/image00081.jpeg)
  
  CONTENTS
  
  Prologue
  
  1
  
  The Greatest Story Ever Told
  
  2
  
  How to Communicate with Aliens
  
  3
  
  Let There Be Light
  
  4
  
  Between the Galaxies
  
  5
  
  Dark Matter
  
  6
  
  Dark Energy
  
  7
  
  My Favorite Elements
  
  8
  
  Why the World Is Round
  
  9
  
  The Invisible Universe
  
  10
  
  Around Our Solar Neighborhood
  
  11
  
  What Earth Would Look Like to an Alien
  
  12
  
  Looking Up, Thinking Big
  
  Glossary
  
  Illustration Credits
  
  Index
  
  ![](Images/image00143.jpeg)
  
  ![](Images/image00108.jpeg)
  
  Prologue:
  
  Walking Dogs to See the Stars
  
  ![](Images/image00100.jpeg)
  
  I decided to become an astrophysicist when I was nine years old. I remember
  the night. The sky was full of stars. The Big and Little Dippers. The planets
  Jupiter and Saturn. A meteor streaked toward the horizon, and I saw what