Russia stunned the world in October 1957 when it announced it had placed the first man-made object in orbit around the Earth, the basketball-sized Sputnik 1.
America replicated the success of Russia three months later when it launched its first satellite, Explorer 1, which discovered the belts of radiation around Earth.
NASA launched this giant balloon, 30 metres in diameter, in 1960. It reflected incoming signals and was the world’s first rudimentary communications satellite.
Developed by RCA Americom, Satcom 1 (launched 1975) pioneered US cable TV broadcasts with high-profile networks and spurned the age of satellite TV.
International Space Station
Construction of the world’s largest man-made satellite began with the launch of the Zarya module in 1998, and is scheduled for completion in mid-2012.
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