During the 20th century humanity came to realize a dream it had since ancient times: the possibility of space travel. Technological innovations, combined with the political climate of the Cold War, made space exploration a reality for the first time in history.
One of the most dramatic moments of the twentieth century occurred on October 4, 1957. The Soviet Union sent a small shiny sphere with four long antennas into space. They called it Sputnik I. Sputnik is a Russian word that means “traveling companion.” The satellite traveled so fast that its ballistic flight continued all the way around Earth.
While the current lunar exploration initiative has been justified as a “stepping stone” toward Mars, human missions to Mars represent a major step up in complexity, scale, and rigour compared to lunar missions.