Abstract: Aiming at constraints on the takeoff mission on the far side of the moon, Guidance navigation and control system (GNC) made a break through in the autonomous takeoff technology, raised an automatic program for soft landing and takeoff, and ultimately took off and ascended into the target orbit punctually and autonomously. The work process of GNC on the Moon is introduced. The autonomous takeoff technology is described, including autonomous celestial positioning, inertial navigation system alignment, launch direction calculation and the autonomous star sensors scheduling strategy. The automatic program for soft landing and takeoff is based on stating parameters by stages and variable length command process mechanism. Combining the autonomous takeoff technology with the automatic program for soft landing and takeoff realized the world’s first sample return from the far side of the moon efficiently and reliably in the Chang’e-6 mission.

Key words: Chang’e-6, the far side of the moon, autonomous, takeoff