The space shuttle Discovery undocked from the International Space Station (ISS) on Tuesday and began its journey back to Earth after a successful mission.
Discovery undocked from the ISS at 1926 GMT and circled the space station to survey and photograph its exterior — customary practice to end such missions — before returning to Earth for a scheduled Thursday landing in Florida.
Before their second and final burn away from the station, the crew used a robotic arm and high-definition cameras to ensure the shuttle’s heat shield had not been compromised by orbiting debris and small meteorites.
The shield must be intact to prevent Discovery from disintegrating as it enters the Earth’s atmosphere at high speed.
During their eight days aboard the ISS, the Discovery crew has transferred 6.9 tonnes of equipment, including new sleeping quarters, a treadmill, and a refrigerator that will store materials for experiments.
They also delivered and installed a new 800 kilogram external tank containing liquid ammonia, which is used to cool the station’s navigation system.
