On 4 October 1957 the Soviet Union launched Sputnik 1 from the Baikonur Cosmodrome, placing the first artificial satellite into Earth orbit. The small metal sphere transmitted radio pulses for weeks and demonstrated that an object could be lofted and sustained in orbit, opening the space age and triggering the US–Soviet space race. It was quickly followed by larger satellites and, within years, crewed spaceflight. The achievement spurred massive investment in rocketry, science education and aerospace.
Satellites came to underpin global communications, weather forecasting and broadcasting, and the positioning and remote-sensing systems now central to mapping cities. GPS, satellite imagery and earth observation became routine tools for navigation, surveying and urban planning.