 Complete the following phrase:  In 1957, the Soviet Union launched the worlds first artificial satellite, Sputnik 1, thus starting the Space Age. Russian cosmonaut Yuri Gagarin became the first human to orbit the Earth, aboard the Vostok 1 manned spacecraft on 12 April 1961. Following the ousting of Khrushchev in 1964, another period of collective rule ensued, until Leonid Brezhnev became the leader. The era of the 1970s and the early 1980s was later designated as the Era of Stagnation, a period when economic growth slowed and social policies became static. The 1965 Kosygin reform aimed for partial decentralisation of the Soviet economy and shifted the emphasis from heavy industry and weapons to light industry and consumer goods but was stifled by the conservative Communist leadership. In 1979, after a Communist-led revolution in Afghanistan, Soviet forces invaded the country, ultimately starting the SovietAfghan War. The occupation drained economic resources and dragged on without achieving meaningful political results. Finally, the 