Living on a world as vast as Earth, it can be easy to forget that our planet is just a tiny speck in a massive universe filled with planets, moons, stars, asteroids, comets, dark matter, and maybe even alien life! In this book, readers in grades 4-9 will learn about Earth's place in the Milky Way and the larger universe, and how humans are learning about the endless frontier of space. This series features a variety of science topics aligned to NGSS standards. From mixing matter to the study of sound waves, each informative book includes a glossary, comprehension questions, and an activity for home or the classroom.