Download or read book The Nine Planets of the Solar System | Guide to Astronomy Grade 4 | Children's Astronomy & Space Books written by Baby Professor and published by Speedy Publishing LLC. This book was released on 2020-12-31 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are nine known planets in our solar system. They are the inner planets, otherwise called as the terrestrial planets, and the outer or Jovian planets. Recently, scientists have re-categorized Pluto as a dwarf planet. In this book, you will read about the characteristics of these nine planets and how they revolve around the Sun. Buy a copy and start reading today.