An astronaut in need of doctors’ care departed the International Space Station with three crewmates on Wednesday in Nasa’s first medical evacuation. The four returning astronauts – from the US, Russia and Japan – are aiming for an early Thursday morning splashdown in the Pacific near San Diego with SpaceX. The decision cuts short their mission by over a month. “Our timing of this departure is unexpected,” Nasa astronaut Zena Cardman said before the return trip, “but what was not surprising to me...