ICO's ten satellites fly about 9, 000 kilometres higher in medium-earth orbit and have a life-span of 12 years.

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ICO's satellites will fly about 9, 000 kilometres higher in medium-earth orbit.

ECONOMIST: Staying in touch | The

Some have even suggested the loose rock regolith on the surface of the moon or Mars as a growing medium, although additional minerals would need to be brought from Earth.

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