Photo: Xinhua

The Long March-5B Y4 carrier rocket that is commissioned to ferry the China Space Station Mengtian laboratory module into orbit, has safely arrived at the Wenchang Space Launch Site in South China's Hainan Province, the Global Times learned from the China Manned Space Agency (CMSA) on Saturday morning. 

Next, the Long March-5B Y4 rocket will carry out general assembly work at the launch pad and other testing work together with the Mengtian module that arrived earlier, the CMSA said in a press release it provided to the Global Times on Saturday. 

China is gearing up smoothly to complete the building of the country's first space station with the Mengtian - third and last part for the basic three-module T structure and the second lab module following Wentian module - to be launched and connected to the current space station combination in October.  

Compared with the Wentian module that was launched in July and hosting experiments with focus on the study of space life sciences, the Mengtian module will be oriented to microgravity scientific research and is equipped with experimental cabinets for fluid physics, materials science, combustion science, basic physics and space technology experiments.

Mengtian also has a payload airlock, allowing the station's small robotic arm to take science payloads and install them on an experiment platform on the module's exterior.

Zhang Wei, director of the Space Utilization Development Center, Technology and Engineering Center for Space Utilization, under the Chinese Academy of Sciences, revealed previously that Mengtian will carry the world's first space-based cold atomic clock system consisting of a hydrogen clock, a rubidium clock and an optical clock. 

"If successful, the cold atomic clocks will form the most precise time and frequency system in space, which should not lose one second in hundreds of millions of years," said Zhang.

Then Shenzhou-14 spaceflight crew led by mission commander Chen Dong are currently in a six-month mission, working and living in orbit in the space station combination.

The crew delivered their first spacewalk with full success at 0:33 am on Friday, the mission lasted some six hours.   

Before Mengtian is launched and connected to the combination, the Wentian module will move to the right side of the Tianhe core module, forming an L-shaped structure, for which Shenzhou-14 taikonauts will perform three complex steering maneuvers to adjust the Wentian to a vertical position with the help of the robotic arm, the Global Times learned from manned space authorities.