The project organisers said the capsules and their contents would experience "conditions which are very close to that of the surface of Mars".

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Experience gained from new journeys to the Moon would be used in "human missions to Mars and to worlds beyond", the president said.

BBC: NEWS | Science/Nature | Bush unveils Moon and Mars plans

This will allow people to experience artificial gravity in space, which may be important for long-term missions to places such as Mars.

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