Four astronauts traveling back to Earth from the International Space Station (ISS) after a medical issue prompted them to evacuate and cut their mission a month short, according to video footage from NASA. US astronauts Mike Fincke and Zena Cardman, Russian cosmonaut Oleg Platonov, and Japanese astronaut Kimiya Yui undock from the ISS after five months in space, and are due to splash down off the California coast at around 0840 GMT on Thursday aboard a SpaceX Dragon capsule. IMAGES