Letters bearing postage stamps can be launched to the International Space Station where the stamps will be franked and returned to Earth, a spokesman for the Russian Space Agency, Sergei Gorbunov, told the Interfax news agency at Baikonur, Kazakhstan, where a Russian rocket is due to lift off to the ISS early Saturday.

The service will cost "from 20,000 to 30,000 dollars" (18,000 to 27,000 euros)," Gorbunov said.

The price is so high because "it costs between 10,000 and 20,000 dollars to deliver one kilogramme (2.2 pounds) of cargo to the station, and 60,000 dollars to return it to Earth. An hour of labour is estimated at costing 18,000 to 19,000 dollars," Interfax quoted him as saying.

Interested parties can purchase the stamps from a special firm that will ensure their delivery to the ISS, he said.

The proceeds will be devoted to "space-related activities," he said.

SPACE.WIRE