Chinese astronauts undock from space station, head for landing

Astronaut Wang Yaping, Zhai Zhigang, and Ye Guangfu on-board the Chinese space station. Credit: CMSE

Three Chinese astronauts packed up, boarded their landing capsule, and undocked from China’s space station Friday in preparation for a return to Earth after six months in orbit.

Commander Zhai Zhigang, astronaut Wang Yaping, and crewmate Ye Guangfu are closing out a 182-day mission, the longest-ever spaceflight by a Chinese crew. They launched Oct. 15 on the Shenzhou 13 spacecraft, and docked with the space station’s Tianhe core module six-and-a-half hours later.

After six months performing experiments, spacewalks, and preparing the station for future expansion, the Shenzhou 13 crew is closing out their mission Friday, targeting a parachute-assisted landing in the Gobi Desert of northwestern China.

The three astronauts floated into their Shenzhou 13 spacecraft and closed hatches with the Tianhe core module Friday, then undocked from the station’s nadir, or Earth-facing, port at 12:44 p.m. EDT (1644 GMT) while the lab soared nearly 240 miles (380 kilometers) above the planet, according the China Manned Space Agency.

The spacecraft was expected to fire thrusters to move a safe distance from the space station, then jettison its orbital habitation module, which will remain in orbit until aerodynamic drag pulls it back into the atmosphere. The ship’s engines will then fire for a deorbit burn to slow down for re-entry, then Shenzhou’s propulsion module will separate, leaving the landing capsule to bring the three astronauts back to Earth.

The re-entry capsule, protected by a heat shield, will encounter temperatures of several thousands degrees. After a brief build-up in G forces, the spacecraft will deploy a main parachute to slow its descent for touchdown at the Dongfeng landing site in the Inner Mongolia region of northwestern China.

Chinese officials did not announce the exact landing time, but it is expected to occur shortly after 9:30 p.m. EDT Friday (0130 GMT Saturday), or 9:30 a.m. Beijing time.

The Dongfeng landing field is near the Jiuquan launch center, where Shenzhou 13 blasted off last October. The previous Shenzhou mission, which returned to Earth last September, became the first mission to land with astronauts at the Dongfeng site. Earlier Chinese missions parachuted into a different part of Inner Mongolia known as Siziwang Banner.

This image shows an animation of the Shenzhou 13 spacecraft undocking from the Chinese space station (top) and a view of Shenzhou 13 as seen from the space station after undocking (bottom). Credit: CMSE

During their stay on the Chinese space station, the Shenzhou 13 astronauts completed a series of experiments and performed two spacewalks.

Zhai and Wang completed the mission’s first spacewalk Nov. 7. The astronauts prepared the space station’s 47-foot (14.5-meter) robotic arm for service, connecting its two main segments and installing a suspension device to help the arm move equipment around the exterior of the laboratory.

Wang, who was a Chinese military pilot before joining China’s astronaut corps, became the first Chinese woman to perform a spacewalk.

The mission’s second spacewalk on Dec. 26 was performed by Ye and Zhai, who deployed an external panoramic camera and tested methods for astronauts on future missions to move objects around the outside of the station.

Both spacewalks lasted more than six hours, and the astronauts wore Chinese-made Feitian space suits.

The Shenzhou 13 astronauts also evaluated the living and working conditions inside the Tianhe core module. They proved out the station’s life support system, which includes technology to recycle urine, sweat, and water vapor into drinking water. The astronauts also tested the station’s stationary bicycle and treadmill to maintain physical fitness during their mission.

The astronauts also spoke to the Chinese public in science education and outreach activities, and celebrated traditional events on the Chinese calendar, such as the Chinese New Year, or Spring Festival, and the Lantern Festival. Wang, who is on her second mission to space, said the astronauts enjoyed Chinese cuisine on the station, such as dumplings, zongzi, mooncakes, and tangyuan.

The Chinese astronauts answered questions from U.S. schoolchildren April 9 in an event hosted by the Chinese Embassy in Washington. Wang said then she was looking forward to returning to Earth, seeing her 6-year-old daughter and running outside on sunny afternoons.

“We have carried out experiments in the space station to study how cell growth and development change under weightless conditions and investigated their variation patterns and mechanisms,” Ye told the U.S. students.

Zhai Zhigang is a 55-year-old major general in the People’s Liberation Army Strategic Support Force. Zhai is on his second spaceflight. He became the first Chinese astronaut to perform a spacewalk in 2008.

Ye, 41, is wrapping up his first mission to space. Like his crewmates, he was a pilot in the Chinese military before joining the country’s astronaut corps.

The Shenzhou 13 mission was the second crew to live and work on the Chinese space station, following the 92-day Shenzhou 12 mission last year. The Shenzhou 13 astronauts will nearly double the Chinese spaceflight endurance record set by Shenzhou 12.

The departure of the Shenzhou 13 crew will leave the Chinese space station unoccupied until the launch of the next long-duration team of astronauts in June. Shenzhou 14 will deliver three more astronauts to the station for another six-month mission.

The first section of the Chinese space station, Tianhe, launched last April on a heavy-lift Long March 5 rocket. The Tianzhou 2 cargo ship launched in May, followed by the Shenzhou 12 launch in June, and the Tianzhou 3 supply mission in September.

The Tianzhou 2 supply ship undocked from the station last month and burned up during re-entry, as designed. China plans to launch the Tianzhou 4 cargo mission in May, then Shenzhou 14 is scheduled to lift off in June.

Later this year, China plans to launch the large Wentian and Mengtian laboratory modules to complete the initial assembly of the space station.

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