From millions of miles away, Mars looks like a bright red star. But it's more than just a spot in the sky! Science has given us many lessons on what else exists in our solar system. Rovers, orbiters, and other spacecraft have sent back information that scientists use to bring us one step closer to landing on Mars ourselves. Full-color photos bring to life the exciting discoveries scientists have uncovered. 21st Century sidebars discuss technological advancements, hypothesize future endeavors and inventions, and solve problems and challenges astronauts might face. An activity at the end lets readers think about what they learned in a hands-on way.