Asked by: Roger Beever, Huddersfield
NASA has developed a sort of jetpack called SAFER (Simplified Aid For EVA Rescue), which fires compressed nitrogen from 24 thrusters to steer the astronaut back to safety if they become detached. Theoretically, astronauts could also vent some gas from their suits or even throw a tool in the opposite direction to push themselves forward. But the problem is that unless the thrust is exactly in line with the astronaut's centre of mass, they will start spinning uncontrollably and very quickly become disorientated. SAFER automatically detects rotation and uses its jets to keep the astronaut oriented the same way.
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