Tonight, the German research icebreaker Polarstern will set out from Tromsø (Norway) on a sea expedition unlike any the world has seen before. Around a month from now, north of Siberia, the Polarstern will be moored to a large floe formed from last year’s ice. The water will freeze around it, enclosing it completely. It will then spend several months encased in the ice floe, during which it will drift several hundred kilometres through the Arctic Ocean, passing close to the North Pole. During the drift, the scientists on board will collect unique data on the Arctic winter. Amongsts the scientists on the Polarstern, are different Swiss teams.