"It is said that you can see the Great Wall from space. Can you see the Sahara Desert and Mount Kilimanjaro from the Tiangong space station? " asked an Algerian student addressing the three taikonauts aboard the China Space Station at an event where taikonauts answered questions from African youths on Tuesday.

"Actually, we cannot see the Great Wall from space. However, when we are above the African continent on a clear day, we can see the Sahara and Kilimanjaro through the porthole. We can also see some big cities," answered taikonaut Chen Dong. 

Chen Dong, Liu Yang and Cai Xuzhe were sent to the China Space Station in June for a six-month mission. In late July, they entered Wentian, the first lab module that docked with the station.