This book is simplified for grades as early as 1st, but can be used for older grades as well. It is roughly 40 pages long and includes 2 pages of information on each planet, dwarf planets, asteroids, comets, meteors, stars, and constellations. It includes a table of contents, glossary, and fun facts box on each topic. Unfamiliar words are highlighted and in bold print and can be found in the glossary.