Astronomers have always had a special need for rapid communication over large distances, partly because of their interest in experiments requiring long baselines. Examples: Eratosthenes’ measurement of the circumference of the Earth; determination of longitude at sea; solar-eclipse tests of general relativity; very-long-baseline interferometry. Of these, at least the second has prompted innovations in communications techniques (beginning with the Greenwich time ball).

More recently, the pressing need to travel widely for clean air and aether, and the international flavour of the resulting collaborations, has given astronomers particular incentive to explore the latest communications innovation: electronic mail.