Expedition 20 to the International Space Station lifted off today at 10:34 GMT from the Baikonur Cosmodrome in Kazakhstan.

Aboard the Soyuz spacecraft are cosmonaut Roman Romanenko, Canadian Space Agency astronaut Robert Thirsk and European Space Agency astronaut Frank De Winne, who are slated to dock with the ISS at 12:36 GMT on Friday. Their arrival marks the expansion of the orbiting outpost's crew to a permanent six.

The existing ISS residents are Expedition 19 commander Gennady Padalka, NASA astronaut Michael Barratt and Japan Aerospace Exploration Agency astronaut Koichi Wakata, who launched to the station on 26 March.

When they do step through the airlock, the new arrivals will mark the first time that representatives all five of the international partner agencies – NASA, the Russian Federal Space Agency (Roscosmos), the Japan Aerospace Exploration Agency, the European Space Agency and the Canadian Space Agency - are simultaneously aloft.

The expanded crew will no doubt toast the landmark with a refreshing drink from the ISS's troublesome urine recycler - recently declared fully operational and now serving "yesterday's coffee" to satisfied customers. ®

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