The Sputnik program () was a series of robotic spacecraft missions launched by the Soviet Union. The first of these, Sputnik 1, launched the first human-made object to orbit the Earth. That launch took place on October 4, 1957 as part of the International Geophysical Year and demonstrated the viability of using artificial satellites to explore the upper atmosphere. The Russian word sputnik literally means "co-traveler", "traveling companion" or "satellite", and its R-7 launch vehicle was desig… (More on Sputnik)