Five billion years ago, a starship passing through our region of space would not have slowed down for a second look. There was nothing to see. No Earth, no sun, no solar system. Nothing but a huge tenuous cloud of gas. Now, as the result of billions of years of evolution, and centuries of scientific research, we can chart our way through the solar system . . . with Sally Ride as our navigator. Starting from the sun and working outward, Sally Ride and Tam O'Shaughnessy take readers on a tour of the nine planets and explain the formation, current conditions, and possibility of life on each. Filled with crisp, full-color photographs and lucid prose, this comprehensive volume untangles the complexities of space and allows readers to feel like masters of the universe.