What is the difference between a comet and an asteroid? What makes up each one? How do have they affected our world in the past—and how will they continue to do so in the future? These questions and more are answered in this volume, which offers a fascinating look at these celestial objects and their impact on our universe. Through stunning full-color photographs and detailed graphic organizers, readers learn about the history of comets and asteroids, their composition and structure, and how they have shaped the formation of our solar system.