Satellites
In October 1957 the Soviet Union shocked the world by launching its first man-made satellite, Sputnik, writes Clive Cookson. Less than five years later space technology went commercial when the US launched Telstar 1, the first communications satellite, which transmitted television broadcasts and telephone calls across the Atlantic.
In 2012, 50 years after Telstar 1 went into orbit, commercial space activities were worth more than $200bn worldwide. Long-distance telephony had driven the expansion of commercial satellites in their early years, but with high-capacity fibre optic cables providing the backbone for intercontinental telecommunications, satellite broadcasting makes up the largest part of the space market.
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