National Geographic’s Little Kids First Big Book of Space introduces galaxies, stars, dwarf planets, the Milky Way, planets, and even the universe itself.
The Mysteries of the Universe: Discover the Best-Kept Secrets of Space by Will Gater analyzes over 100 different celestial objects to reveal their secrets.
The Planets: The Definitive Visual Guide to Our Solar System from the Smithsonian and published by DK uses photos from NASA and 3-D diagrams to introduce the planets.