In this screen image captured at Beijing Aerospace Control Center released by Xinhua News Agency, Chinese astronauts from left, Liu Yang, Chen Dong and Cai Xuzhe salute after entering the space station core module Tianhe on Sunday, June 5, 2022.  China on Sunday launched the new three-person mission to complete work on its permanent orbiting space station.  (Li Xin / Xinhua via AP)

Astronauts arrive at China's Tiangong space station to complete construction