it was a physical class．but it was nothing like previous ones — the class was “attended” by over 60 million students across china, and the teacher was not even on the planet: she was 340 kilometers above the earth． “hello, everyone．i’m wang yaping．i’ll host your lecture today．” smiling to the camera, wang, china’s second female astronaut, started her video class on june 20 on board the tiangong-1 space station
