Long missions in space are damaging astronauts' brains, a new scientific study shows. Researchers at the University of Florida studied brain scans of 30 astronauts before and after they travelled beyond the Earth's atmosphere. Scientists now recommend frequent flyers wait three years after longer missions so their brains can reset.

The study reveals that the brain’s ventricles expand significantly in astronauts who carried out missions of at least six months.

It also shows that less than three years after missions may not allow enough time for the ventricles to fully recover.