Mars is millions of miles away from where you stand. The race to get from here to there has been going on for decades. With every passing day, that journey through the stars has changed from science fiction to a scientific factual possibility. New inventions have led the way toward space exploration. What can we take with us into the future, and what will we need to leave behind on Earth? Full-color photos show the new advancements that will get us there. 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.