Why is the Moon not a planet?

"What's the difference between a planet and a moon? What exactly is a planet? How did the moon form and how does it affect Earth? This book explores one of our most familiar nighttime sights, the moon. Readers will love discovering the answers to these often-asked questions. Easy-to-understand diagrams and fact-filled text help explain concepts in an age-appropriate and fun way. Hands-on science projects let readers complete their own engaging experiments, while sidebars add useful information to give readers a well-rounded and memorable reading experience"--Provided by the publisher.