Sealed behind the steel doors of two bunkers in a Beijing suburb, university students are trying to find out how it feels to live in a space station on another planet, recycling everything from plant cuttings to urine.
They are part of a project aimed at creating a self-sustaining ecosystem that provides everything humans need to survive.
Four students from Beijing University of Aeronautics and Astronautics entered the Lunar Palace-1 on Sunday with the aim of living self-sufficiently for 200 days.
They say they are happy to act as human guinea-pigs if it means getting closer to their dream of becoming astronauts.
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