Chinese astronauts complete second spacewalk outside space station

Chinese astronauts Nie Haisheng and Liu Boming accomplished a nearly six-hour spacewalk Friday outside the core module of the country’s new space station, installing a coolant pump and lifting a panoramic camera on the exterior of the complex.

Nie and Liu exited the airlock of the Tianhe core module at 8:38 p.m. EDT Thursday (0038 GMT Friday), according to the China Manned Space Agency.

The two astronauts completed their planned tasks supporting the assembly of the Tiangong space station, Chinese officials said.

One of the highlights of the spacewalk was the the installation of a backup “extended pump set” to help flow liquid coolant through a thermal control system loop regulating temperatures inside the space station. The coolant dissipates heat generated by equipment inside the outpost, and helps ensure steady and comfortable temperatures throughout the station.

Nie and Liu accomplished four steps to complete mechanical and fluid connections with the new pump, the China Manned Space Agency said.

During their spacewalk, the astronauts moved around the exterior of the Tianhe module with the aid of a robotic arm.

The astronauts also raised a panoramic camera outside the station re-entering the Tianhe module at 2:33 a.m. EDT (0633 GMT), completing a 5-hour, 55-minute spacewalk.

Tang Hongbo, the third space station crew member, assisted the spacewalker from inside the Tianhe core module.

The astronauts wore Chinese-made Feitian spacesuits for the spacewalk, which followed a nearly seven-hour excursion July 4 by Liu and Tang. During that spacewalk — the first conducted from the new Chinese space station — astronauts installed foot restraints, a work platform, and a camera outside the Tianhe module.

The spacewalk completed Friday was the third in the history of China’s space program.

China’s first spacewalk was accomplished on the Shenzhou 7 mission in 2008. On that flight, Liu and crewmate Zhai Zhigang briefly exited the hatch to the Shenzhou 7 spacecraft and waived a Chinese flag for a television audience.

The three-man station crew launched June 16 on China’s Shenzhou 12 spacecraft, beginning a planned three-month expedition. The astronauts are the first residents aboard China’s space station.

Assembly of the Tiangong station began in April with the launch of the Tianhe core module on a heavy-lift Long March 5B rocket. China launched a Tianzhou cargo ship to dock with the Tianhe module in May, followed by the arrival of the first Shenzhou crew ship in June.

The Shenzhou 12 astronauts are in the home stretch of their mission. Before returning to Earth in mid-September, the crew will perform circumnavigation and radial rendezvous test with their crew capsule, CMSA said.

A new Tianzhou supply freighter is scheduled to launch to the space station on a Long March 7 rocket in September, followed by the launch and docking of the next space station crew on the Shenzhou 13 spacecraft in October.

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