Millions of miles from Earth, a small, rocky world circles the Sun. Mercury may be the smallest planet, but it holds big interest for young readers! This book explains concepts like craters, space probes, and planetary orbits, all in simple language that's perfect for any classroom or library. In the back of the book are an index and glossary, plus additional recommended reading. A shareable craft idea teaches how to make your own craters out of plaster and recycled newspaper.