NASA is cutting short a mission aboard the International Space Station after one astronaut fell ill, triggering the first medical evacuation in the station's 25-year history.

The four-member US-Japanese-Russian crew will return to Earth early even though NASA says the astronaut is stable and it is not an emergency.

The agency says it's also cancelled a planned spacewalk — and will leave fewer astronauts on board the station for now.

Guest: Dr Sara Webb, astrophysicist at Swinburne University of Technology

Producer: Anne Barker