(London Telegraph) Astronauts putting their lives at risk on space missions because they are not getting enough sleep, a new study has found.

A new study by Harvard Medical School has found many astronauts suffer serious levels of sleep deprivation that could be putting their lives in danger.

Scientists studied the sleep patterns of 64 astronauts on 80 space shuttle missions and 21 International Space Station (ISS) crew members before, during and after spaceflight.

They found that on average astronauts snatch less than six hours sleep on orbiting space shuttles and just over six hours on ISS missions.

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