The Secrets of Mercury (Planets)

Mercury is the smallest planet in our solar system, but it still has secrets!  From ancient cultures that watched the skies, to modern scientists who send machines into space, humans are passionately curious about the planet closest to the Sun.  Learn about Mercury's discovery, what it would be like to visit, and what scientists still want to know.  Vivid photos and illustrations, scientist spotlights, and sidebars help unlock the secrets of Mercury.