Sky high

More than 200 airships will be launched into the stratosphere by the year 2000, the Japanese government announced. Floating 20 km above the Earth's surface, these 260-m-long zeppelins will be used like normal communications satellites, specially for mobile phones. Costing one-tenth the price of a conventional communications satellite, these airships will live longer, claims the government. Moreover, their relatively low altitude -- the orbits of the lowest satellites are at least 30 times as high -- means that the ground transmitters can be smaller.