The first satellite was placed into geostationary orbit in 1964, just 19 years after Sir Arthur's paper.

BBC: NEWS | Technology | Arthur C Clarke: predictions

This development launcher will take 12 tonnes towards geostationary orbit.

BBC: Ariane 5: A short history

But unlike Iridium's 66 low-orbit birds, Astrolink will cover the earth with only four high-orbit geostationary fliers.

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