Four astronauts evacuated from the International Space Station (ISS) have landed back on Earth, after their stay in space was cut short by a month due to a “serious” medical issue.
The astronauts arrived on the ISS on 1 August expecting to complete a standard six and a half month stay.
But last week, a scheduled spacewalk was called off at the last minute. Hours later, Nasa revealed a crew member had become ill.
It is the first time astronauts have been evacuated due to a health issue since the station was put into Earth’s orbit in 1998.
BBC science correspondent Pallab Ghosh explains how Nasa deals with medical emergencies in space.
