NASA has carried out its first-ever medical evacuation from the International Space Station, sending four astronauts back to Earth earlier than planned. One of the four astronauts required medical care, prompting NASA to shorten the mission by more than a month. Officials did not identify the astronaut or disclose the nature of the health issue, citing medical privacy, and stressed it was not an emergency. Launched in August, the astronauts were scheduled to remain on the ISS until late February. NASA said bringing the astronaut home was safer than waiting another month, marking the agency's first medical evacuation in 65 years of human spaceflight.