China's high-stakes mission to the moon's 'hidden' side

China is poised to send a robotic spacecraft on a round trip to the moon's far side in the first of three missions that will pave the way for an inaugural Chinese crewed landing and a base on the lunar south pole.

This week, China is expected to launch its Chang'e-6 mission using a backup spacecraft from a 2020 trip, and collect soil and rocks from the side of the moon that permanently faces away from earth.