Sputnik 1 was the first artificial satellite. Earth's largest artificial satellite is the International Space Station. Two days later, the Soviet Union launched Sputnik 1, the first artificial satellite. Mariner 9 was launched in May 1971 and became the first artificial satellite of Mars. Currently the largest artificial satellite ever is the International Space Station. A military satellite is an artificial satellite used for a military purpose. On October 4, 1957, the Soviet Union launched Sputnik 1, the first artificial satellite. In "The Terminator 2029", Skynet is housed within an artificial satellite in orbit around Earth. Luna 10 (March 1966) became the first artificial satellite of the Moon. Explorer 1 became the United States' first artificial satellite on 31 January 1958. An amateur radio satellite is an artificial satellite built and used by amateur radio operators. In 1957, the USSR launched the first artificial satellite, "Sputnik 1". On 4 October 1957 the Soviet Union launched the world's first artificial satellite, Sputnik 1.