At the Russian words “Let’s go,” rockets fired and Yuri Gagarin became the first person to blast into outer space, forever altering human perception of what was possible, and sending U.S. engineers desperately scrambling to match his feat. Today, spaceflight may seem routine, now that man has reached the moon and NASA’s space shuttle program recently logged its 100th trip. Many hope the next big space project will be to deliver people to Mars, a journey that could take up to two years of space travel. NASA has no formal Mars program but continues to explore the planet using robotic craft.