Primary students in Chongqing display their hand-made model of the Shenzhou X spacecraft on Thursday.Chen Shichuan / For China Daily

Two automatic dockings between the unmanned Shenzhou VIII and Tiangong-1 were conducted in 2011, and an automatic and manual docking took place between the manned Shenzhou IX and the space module in 2012.

The successful missions saw China become the third country to master the technology, following the United States and Russia.

After the Shenzhou X mission, China will enter the space lab stage, the final stage before it builds a space station around the year 2020.

Qi Faren, former chief designer of the Shenzhou spacecraft, said China needs to master four vital technologies in order to launch the space station.

So far, it has learned how to carry out extravehicular activity, and acquired the space rendezvous and docking technology thanks to the previous missions.

Solving a supply problem and recycling air and water in the space lab for astronauts on long-duration missions remain to be tackled.

Zhou Jianping, chief designer of the manned space program, said in March the Tiangong-2 space lab will be launched in two years, followed by the launch of a space freighter.

The freighter will conduct a fueling experiment with the space lab, which is expected to solve the supply problem.