The reentry module of Shenzhou-11 lands in a pasture area in Siziwang Banner, Inner Mongolia Autonomous Region, on November 18 （XINHUA） 

Siziwang Banner, a sparsely populated pasture area in north China's Inner Mongolia Autonomous Region, was once the fiefdom of the descendants of Genghis Khan's younger brother. Today, it is the primary landing site for the Shenzhou, the series of Chinese spacecraft which carried the first Chinese astronaut into space, standing witness to the progress of China's manned space program.

At 1:59 p.m. on November 18, Siziwang welcomed back the Shenzhou-11 with its two astronauts on board. The spacecraft, which had darted ceaselessly in space for more than a month, returned safely, marking the longest stay in space by Chinese astronauts.

As the reentry module—the part of the spacecraft which returned to Earth—touched down at the site, the hatch swung open and the two astronauts, Jing Haipeng and Chen Dong, appeared, looking to be in good condition. They were greeted by a squad of doctors and emergency rescuers and were quickly escorted onto a helicopter.

"The Tiangong-2 and Shenzhou-11 manned space mission was a complete success," announced Wang Zhaoyao, Director of China's Manned Space Program Office, at a press conference held close on the heels of the astronauts' successful return. He said the feat was important for China's space mission, especially for building and operating space stations.

The Shenzhou-11 saga started with the launch of the spacecraft from the Jiuquan Satellite Launch Center in the Gobi Desert on October 17. Two days later, the spacecraft completed an automated docking with the Tiangong-2, the lab that had been sent into orbit a month earlier to facilitate manned space missions. The two astronauts lived in the space lab for 30 days, conducting scientific and technical experiments.

On November 17, when it was time to return to Earth, the Shenzhou-11 separated from the space lab, starting the re-entry process.

  

In a space lesson on November 17, astronaut Jing Haipeng explains the condition of the silkworms they raised in the Tiangong-2 space lab（XINHUA） 

Life in space 

"This is Beijing. Good morning!" Every morning, Jing and Chen would start their new day in space with this greeting from Earth.

Their life in the Tiangong-2 was well-documented by video cameras and shared online. On November 17, a space lesson featuring the experiments conducted in space was broadcast on the Internet where the pair added a human touch to sophisticated devices.

Taking care of six silkworms was one of their daily chores. Jing held up a transparent cylindrical container close to the video camera, showing a worm, the new guinea pig in space. The former fighter pilot from the People's Liberation Army Air Force explained that the sixth silkworm was not doing well in its new space home. It did not look strong and barely moved. Nor had it spun a cocoon as the other five had.

Although the silkworm experiment was scheduled to end on October 26, Jing said they would not give it up. He wished a miracle would happen to the ailing worm.

Breeding silkworms in space was part of the three experiments devised for the astronauts by middle school students from Hong Kong to find out how the space environment affected natural properties. For example, if the worms would produce tougher and thicker silk in space. Wang said the cocoons spun in space will be studied by researchers to see if they have new properties.

  

Astronauts Jing Haipeng (right) and Chen Dong are interviewed by Xinhua News Agency on November 16 （XINHUA） 

In addition to raising silkworms, the astronauts also grew vegetables. Wang Yaping, the second Chinese woman to fly into space and anchor for the space lesson, described how vermiculite, a mineral containing air, water and nutrients, was used as a soil substitute to grow lettuce in space. When the seeds sprouted on the fifth day, Jing and Chen took photographs first and then thinned out the seedlings with tweezers so that only the strong ones were left to grow. The delighted gardeners also injected air into the roots of the lettuce so that the plants would have their quota of fresh air.

The lettuce flourished, appearing greener than their brethren on Earth, Wang Yaping said. However, they were not destined for salads immediately. Wang Yaping said they would be brought back to Earth to be studied but in future, astronauts would be able to eat the vegetables they grow in space and breathe the oxygen the plants produce.

Another technology demonstrated in the space lesson was a brain-computer interface, which allows astronauts to work computers with their mind.

Wang Yaping put on a headset that can read electroencephalogram signals, the electrical activity of the brain, and demonstrated how she could command four figurines displayed on the screen near her. She gazed at one and in her mind, thought of raising the left hand. Correspondingly, the figurine raised its left hand. She then willed another to say what she was thinking and it echoed her thought, "I wish children all over the country grow up to be healthy."

Wang Yaping said a similar experiment was conducted in space to test whether the models built on ground work in space as well.

Gao Ming, Director of the Technology and Engineering Center for Space Utilization under the Chinese Academy of Sciences, said at the press conference on November 18 that the experiments conducted on the Tiangong-2 this time exceeded those carried out during previous manned space missions from China.

They included loading a cold-atom clock in the space lab to improve timekeeping for satellite navigation. Called the most accurate timekeeper in the universe, the clock gets its name from the use of laser-cooling technology to cool down and thereby immobilize atomic particles so that their effect on the clock is minimized. While a mechanical watch loses almost one second a day and a quartz watch about one second every 10 days, the cold-atom clock will not lose a single second in 30 million to 300 million years in space. Other sophisticated devices on board included a detector for gamma ray burst (GRB) polarizations. GRBs are short, extremely luminous bursts of gamma radiation from an unknown astronomical source, like a dying star. The detector, jointly developed by Chinese and European scientists, will be used to investigate the nature of GRBs as well as the origin and evolution of the universe.

"So far, we have managed to observe GRBs, solar X-ray bursts and pulse signals from the Crab Nebula (the remains of a massive star). We will continue these observations and scientists will analyze and research these data," Gao said.

The Tiangong-2 also has imaging equipment to observe the land, oceans and atmosphere of Earth and test remote-sensing capabilities.

"Preliminary tests showed that the observation equipment worked smoothly. They obtained abundant data and clear high-quality images that have been released on our data service platform," Gao added.

In addition, the astronauts brought back samples of a dozen materials that will also be studied to understand the physical and chemical rules governing material growth in microgravity, Gao said.

There were also experiments and research on the astronauts' health and movement abilities, as well as studies on space science and applied technologies and control of the companion satellite's flight and observation, Wang Zhaoyao said.

  

President Xi Jinping has a phone conversation with two orbital astronauts on November 9（XINHUA） 

Home away from home 

Video clips show the two astronauts were at home in the Tiangong-2.

Wang Yaping said the Tiangong-2 had been stocked with nearly 100 varieties of food, including staples, snacks, drinks and even seasonings. The meals featured in the space lesson saw them tucking with relish into beef with potatoes, barbecued chicken, black mushrooms, yams, stir-fried rice with meat and vegetables, as well as seaweed and egg soup. Jing celebrated his 50th birthday in space with a miniature birthday cake.

Every day, the astronauts exercised to stay healthy, running on a treadmill, pedaling a stationary bike and working out with chest expanders.

"Pedaling a bike in space is different from riding one on the ground," Chen said. "It is difficult and exhausting."

Huang Weifen, deputy chief designer at the Chinese Astronaut Research and Training Center, said at the press conference the two astronauts showed good teamwork. "It didn't take Jing and Chen long to get used to the space environment," she said. "They carried out all operations and followed all instructions accurately."

Huang, an expert in automation science and electrical engineering, has been selecting and training astronauts.

"The mission helped us accumulate rich experience in managing astronauts… The comprehensive capabilities of our astronauts were improved, providing strong support for long space missions in the future," she said. "The success of the Shenzhou-11 mission showed that our country is capable of sending astronauts into space for long periods."

Next year, the third batch of astronauts will be selected. "Besides military pilots, we will select engineers majoring in aerospace technologies so that they can become aerospace engineers," Huang said.

More developments are in the pipeline as China's manned space program moves forward. A cargo spacecraft is scheduled to dock with the Tiangong-2 next year, and by 2020, a permanent space station will be put into orbit.

 

President Xi Jinping visits the command center of China’s manned space program in Beijing （XINHUA）

 

Chen Dong receives an ultrasonic physical exam in the Tiangong-2 space lab on October 30（XINHUA）

Keeping in Touch 

"No, I have not met any aliens so far. But I am beginning to enjoy my weightless state, now that I have got used to it." 

Once it would have been the stuff of sci-fi movies. But now this is an actual occurrence. It comes from the diary of Chen Dong, the 38-year-old astronaut who returned to Earth on November 18 after a 33-day stint in space. 

Although high up in the sky, modern communication technology kept Chen and his fellow voyager Jing Haipeng close to Earth dwellers. The two astronauts shared their diaries online and interacted with netizens from time to time. 

At 10:05 p.m. on October 19, his first day in the Tiangong-2 space lab, Jing wrote his first entry. In reply to a netizen's query about their meals and sleep, he wrote, "[We] have a pretty busy work schedule. Now [we are] very sleepy." 

He said they had been busy docking the spacecraft with the space lab earlier in the day, so they barely had time for meals. They ate some snacks for brunch and heated up some noodles and rice but had no time to eat them. They were going to make up for the lost meal at night, Jing said. 

When Jing celebrated his 50th birthday in space on October 24, he received gifts from many Chinese children—mostly space-themed paintings. Jing wrote back, encouraging the children to cherish their dreams and pursue them fearlessly. 

On November 9, President Xi Jinping visited the command center of the manned space program in Beijing and had a phone conversation with the two astronauts. 

On November 16, on the eve of their departure from the space lab, the two were interviewed by Xinhua News Agency. Jing said they were preparing for their return journey, collecting and storing data, tidying up the space station and packing up. 

Chen said while he felt sad about leaving the Tiangong-2 since it was their home in space, he was happy and excited about returning to Earth. 

The astronauts' diaries are a window to their life in space. According to Xinhua, by the time they returned, the diaries had been read by more than 100 million people online. 

Copyedited by Sudeshna Sarkar 

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