In the summer of 1996, 31-year-old Yang Liwei was informed that he could participate in the first round of physical examinations for China's space program. He had no idea at the time that he would go on to become the first Chinese person to go beyond the earth's atmosphere.

After passing the first round of tests, he was called to Beijing for the second round. "I was so thrilled that I went three days before schedule, and the nurse made fun of me for being 'too proactive,'" Yang recalled.

It has been 14 years since he made history. During that time he has witnessed the growth of China's manned spacecraft program. He has become one of the national heroes known as taikonauts, a compound word from taikong, meaning space in Mandarin, and astronaut, and specifically refers to a person who travels in space for the Chinese space program.

On January 4, Yang together with 10 other taikonauts renewed their oath before a national flag at the China Astronaut Research and Training Center.

"I am willing to devote my whole life to manned spacecraft endeavor with undaunted courage and selflessness."

This year's January 5 marked the 20th anniversary of the establishment of the Taikonaut Corps of the People's Liberation Army (PLA) of China.

"I've been to space three times, but I still have more goals and dreams. As we said in our oath 20 years ago, we will continue to face new tasks and challenges," said Jing Haipeng, who has flown on three missions: Shenzhou 7 in 2008, Shenzhou 9 in 2012 and Shenzhou 11 in 2016, during an interview with China Central Television (CCTV).

China's manned spacecraft program can be traced back to the 1970s. After Dong Fang Hong I, the country's first space satellite, was launched in April 1970, Qian Xuesen, renowned Chinese engineer and then Director of the Fifth Academy of the Ministry of National Defense, proposed that China should start its own manned spaceflight initiative.

However, the project was delayed due to a lack of expertise and a weak national economy. Nevertheless, the trial and error project laid a solid base for future development.

In 1992, the Central Government introduced a manned spaceflight project and a three-step development strategy, Project 921, which included launching a crewed spacecraft, completing a spacewalk mission and building a larger permanent space station. From then on, the country's space program has enjoyed stable advancement.

In November 1999, the first unmanned launch of the Shenzhou spacecraft, Shenzhou 1, took place. As a prototype, the spacecraft showed the performance and reliability of China's carrier rocket. And the following launch of unmanned Shenzhou spacecraft led to the successful take-off of Shenzhou 5, China's very first manned spaceflight, with Yang aboard, in 2003.

"This is a glorious page in the history of our motherland, and also the most important day of my life," Yang said to the cheering crowd right after he stepped out of the spacecraft cabin on his return.

After Shenzhou 5, China has successfully conducted five space missions. Behind each of them was a rigorous training program and numerous tests for taikonauts and researchers.

Wang Yaping is the second female taikonaut to be named by the China National Space Administration, and the second Chinese woman in space. During her selection test, Wang asked Yang what is the most difficult thing about being a taikonaut. Yang answered in one word: studying. They need to cram a yearlong advanced mathematics course into three months.

During the day, the taikonauts take courses and train, while at night they review what they've learned and prepare for the next day's courses. Sleeping is a luxury they just cannot afford.

Besides basic knowledge, the taikonauts also have to memorize the flight manual, which includes millions of words in nine hefty books. They must each complete any of the operations from tens of thousands of instructions smoothly even with their eyes closed.

Acclimatization training is also essential. The weightlessness training requires the taikonauts to stay in a high-speed centrifuge for 40 seconds. The grueling fast gravitational acceleration distorts their face, puts their chest under pressure, and prevents lifting their arms freely.

Keeping in peak physical condition is of course a priority. It has been over two decades since Liu Boming, one of the three taikonauts who completed the Shenzhou 7 mission in 2008, joined the Taikonaut Corps of the PLA. He has kept his weight change to within 1 kg over the years. Liu, now 52, said a recent physical examination result showed that his body index now was superior to that in his 30s.

However, risks still exist despite exacting preparation and countless training sessions, which may put taikonauts in severe danger. When Zhai Zhigang was on his spacewalk during the Shenzhou 7 mission in 2008, a fire alarm in the orbital module sounded repeatedly.

"I felt my blood freeze when I heard the alarm," Zhai remembered. Within four minutes, Zhai, together with his fellow taikonauts Liu and Jing, reported that it was a false alarm, but despite that the fear and urgency felt was real.

Backroom heroes

The names of taikonauts who have completed the six manned spaceflight missions are household names. But behind them are several unsung pilots who haven't had the chance to fly but are no less dedicated to China's space mission.

Among the first batch of 14 taikonauts, eight people have been to space, five retired, while Deng Qingming is the only one among them who is still in active service but has not been on a mission.

Deng has been the backup astronaut for three missions. The closest he got to flying was the Shenzhou 11 mission in 2016, however the day before the launch he was told to stand down.

But he didn't complain. Right after Shenzhou 11 was launched, Deng devoted himself to ground support work. "My colleagues are in space, but my job is not over until they are back safe and sound," he said.

Deng didn't see being a backup as a failure, but an episode of life. "I will stay the course, because only when you work as hard as you can do others do the same, and the entire team unites as one," he said in an interview with news portal People.com.cn.

Copyedited by Francisco Little

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