China's bold plan to land an unmanned spaceship on the moon before returning to Earth has moved another step forward with a test craft shifting into lunar orbit to conduct further tests, state media reported Sunday.

The service module of a lunar orbiter that flew back to Earth in November had been sitting in a position that brought it into sync with Earth's orbit, known as the second Lagrange point. It had separated from the orbiter in November.

The craft, loaded with support systems for operating a spaceship, will collect further data to aid planning of the 2017 Chang'e 5 mission, state broadcaster China Central Television said.

Chang'e 5 is being designed to make a soft landing on the moon and collect at least 2 kilograms (4 pounds) of rock and soil samples before returning to Earth.

If successful, that would make China only the third country after the United States and Russia to meet such a challenge.

China's lunar exploration program has already launched a pair of orbiting lunar probes, and in 2013 landed a craft on the moon with a rover onboard. None of those were designed to return to Earth. China also has hinted at a possible crewed mission to the moon.

China sent its first astronaut into space in 2003, the only other country after Russia and the U.S. to achieve manned space travel independently. It also has launched a temporarily crewed space station.

China's program has received Russian assistance, but has largely developed independently of America's, which is now in its sixth decade of putting people into space.