Chinese astronauts completed the country's first tandem spacewalk. They worked for seven hours outside the new Tiangong space station in Earth orbit on Sunday while wearing new sets of spacesuits.

The construction of Tiangong is a significant step forward in China's ambitious space program, which has already seen the country land a rover on Mars and send probes to the Moon.

Last month, three astronauts launched into space to become the station's first crew and will stay for three months in China's longest crewed mission to date.

 Cosmonauts Prepare For the Arrival of Russian Module in the ISS After A Seven-Hour Spacewalk
(Photo: Wikimedia Commons)
Russian cosmonauts Oleg Kotov and Maxim Suraev (out of frame), both Expedition 22 flight engineers, participate in a session of extravehicular activity (EVA) as maintenance and construction continue on the International Space Station. During the spacewalk, Kotov and Suraev prepared the Mini-Research Module 2 (MRM2), known as Poisk, for future Russian vehicle dockings. Suraev and NASA astronaut Jeffrey Williams, commander, will be the first to use the new docking port when they relocate their Soyuz TMA-16 spacecraft from the aft port of the Zvezda Service Module on Jan. 21. Earth's horizon and the blackness of space provide the backdrop for the scene.

According to the China Manned Space Agency, two of them left the station early Sunday morning for a seven-hour spacewalk at Tiangong.

"The safe return of astronauts Liu Boming and Tang Hongbo to the Tianhe core module marks the complete success of the first spacewalk in our country's space station construction," the space agency said per Phys.org.

According to state media, their tasks included raising a panoramic camera outside the Tianhe core module and testing the station's robotic arm, which will be used to move subsequent modules around the station.

The astronauts set foot brakes on the robotic arm. They carried out other assembly work with its assistance.

Shenzhou 12's Feitian Spacesuits

Television video showed the astronauts putting on their spacesuits and undergoing health checks while exercising in preparation for the spacewalk.

According to a statement from China Manned Space, the astronauts wore a "new-generation homemade [extravehicular mobility unit] spacesuits."

Feitian, which means "flying to space," is the name given to the spacesuits.

Later, Liu and Tang were seen unlocking the hatch and exiting the module individually, dressed in freshly manufactured suits weighing around 130 kilos.

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"Astronauts Liu Boming and Tang Hongbo have successfully [exited] the module from the Tianhe core module, and also completed the installation of foot limiter and extravehicular workbench on the robotic arm," the statement said per ABC.net.au.

"Follow up, with the support of the robotic arm, they will cooperate with each other to carry out the assembly of relevant equipment outside the space station," the statement added.

Trip commander Nie Haisheng, a renowned air force pilot on his third space mission, provided help from within the station.

This was the first of two planned spacewalks for the mission, each of which was projected to take six or seven hours.

Shenzhou 12 Mission Background

It was also the first time Chinese astronauts had ventured outside their spaceship since 2008. After the Soviet Union and the United States, Zhai Zhigang made China the third country to accomplish a spacewalk.

The group conducted over 6,000 hours of training to get ready.

By the end of next year, the Chinese space agency plans 11 launches, including three additional crewed missions. They will send two lab modules, as well as supplies and astronauts, to expand the station.

China wants to create its own orbiting outpost was fueled in part by a US restriction on its astronauts participating in the International Space Station, a joint venture of the US, Russia, Canada, Europe, and Japan.

The ISS is scheduled to be decommissioned in 2024, while NASA has stated that it may continue operational until 2028.

Tiangong is planned to last at least ten years, and China has stated that foreign collaboration on the station is welcome.

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