The probe entered the earth-moon transfer orbit as scheduled, with a perigee of 200 kilometers and apogee of 380,000 kilometers. It landed on the moon on December 14 to become China’s first spacecraft to soft land on the surface of an extraterrestrial body.

The country’s first moon rover separated from the lander early the next day. The two photographed each other on the moon’s surface in the night of December 15.

The Chang’e-3 mission marked completion of the second phase of China’s lunar program, which includes orbiting, landing and returning to Earth. The lunar program will then enter the next stage of unmanned sampling and returning, which will include Chang’e-5 and 6 missions. China plans to launch lunar probe Chang’e-5 in 2017, according to the State Administration of Science, Technology and Industry for National Defense.

“The program’s third phase will be more difficult because many breakthroughs must be made in key technologies such as moon surface takeoff, sampling encapsulation, rendezvous and docking in lunar orbit, and high-speed Earth reentry, which are all new to China,” said the administration’s spokesman Wu Zhijian.

As the backup probe of Chang’e-3, Chang’e-4 will be adapted to verify technologies for Chang’e-5, according to Wu.

China’s Chang’e-1 and Chang’e-2 missions were in 2007 and 2010.