Sputnik artwork This Soviet spacecraft the first ever spacecraft to reach Earth orbit was launched on October by the Soviet Union The hammer and sickle symbol of the USSRs flag is in the background at left Sputnik was a highly polished aluminium alloy sphere centimetres in diameter with four long antennas attached to it It transmitted radio signals back to Earth for a period of days The following year Sputnik burned up as it reentered Earths atmosphere on January The launch of Sputnik took the USA by surprise starting what became known as the Space Race between the USA and USSR
