China is making final preparations for the launch of a three-person replacement crew for its orbiting space station that will mark a further step toward a possible crewed mission to the Moon and explo

Astronauts Chen Dong, Chen Zhongrui and Wang Jie attend a see-off ceremony for the Shenzhou-20 spaceflight mission at Jiuquan Satellite Launch Center near Jiuquan, Gansu province, China. China Daily via REUTERS ATTENTION EDITORS - THIS PICTURE WAS PROVIDED BY A THIRD PARTY.

A crew of Chinese astronauts headed for orbit Thursday to begin a six-month-long mission aboard the Tiangong space station.