Tilt bed is used for preparing for weightlessness, because in space the body liquids will be be distributed evenly in the body; on Earth the majority of the liquids are gathered in legs and lower parts of the body because of the gravity.
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Paolo Nespoli, ESA's Italian astronaut, will travel to the International Space Station (ISS) on 15 December for a long-duration mission called MagISStra and serve as flight engineer for Expeditions 26 and 27. This will be the third six-month mission by a European astronaut on the Station.