Join Dr. H and BB as they continue to explore the planets in our Milky Way. Starting from Mercury, the planet closest to the sun, they land on each one to experience firsthand how different they are from their home planet, Earth! Along the way, they land in some sticky situations as they learn exciting facts about the planets and the rest of the universe in this wacky adventure series. Come along and test your knowledge of the planets with the new group discussion questions added to the book.