There are typically three astronauts on board China's space station on six-month missions. For the first time, a crew of six is working together on board the station. The Shenzhou-20 crew has been in orbit for over 200 days and is now conducting joint scientific experiments with the newly arrived Shenzhou-21 crew. The space station remains in stable condition and is fully capable of supporting two astronaut crews simultaneously. #SpaceChina | CGTN