Interview with Pang Zhihao: From returning, leaving the cabin to follow-up recuperation, what barriers do astronauts need to pass to "go home"?

Beijing, September 17( China News Network) Title: Interview with Pang Zhihao: From returning, leaving the capsule to follow-up recuperation, what barriers do astronauts need to pass to "go home"?

Author Ma Shuaisha Guo Chaokai

On September 17, the Shenzhou XII "space business trip" trio successfully returned to Earth and successfully landed on the Dongfeng landing field. From the return of the space station, out of the capsule to the follow-up recuperation, what barriers do astronauts need to pass to "go home"? The reporter of China News Network interviewed Pang Zhihao, chief scientific communication expert of national space exploration technology, for authoritative interpretation.

Just as the doors and windows are closed and water and electricity checked before traveling on the ground, before astronauts leave the space station and the core module, packing items, cleaning and other work are essential. Pang Zhihao said that before the astronauts return, they should first sort out the space station, sort out the cargo into categories, and prepare for follow-up work, such as transferring useful things to the core module, putting garbage into the Tianzhou-2 cargo spacecraft, and taking the garbage away when Tianzhou-2 returns in the future.

When it comes to the return process of "God TWELVE", Pang Zhihao summarizes it with "short time, many actions, difficult technology, and high requirements". He said that from braking and decelerating, free coasting to re-entering the atmosphere and recovering landing, the whole process may only take about 50 minutes, but there can be no problems in every link.

For example, when the return capsule re-enters the atmosphere, if the angle is too large, the return capsule will be too fast, the maximum overload exceeds the standard, the astronauts cannot bear it, and the return capsule will even burn in the atmosphere like a meteor; if the angle is too small, the return capsule will pass by the edge of the atmosphere and cannot return.

Therefore, each stage must be carefully designed and considered. "After the return capsule lands smoothly and smoothly, the return capsule disposal personnel should first check the return capsule, such as whether there is any residue of the reverse thrust engine propellant, and use a special γ ray source protective cover to cover the altimeter at the bottom of the return capsule to γ source to prevent radiation from causing harm to rescuers." Pang Zhihao said.

After completing these operations, after opening the hatch, the astronauts could not come out immediately. Pang Zhihao explained that from the weightless environment to the ground environment, astronauts need to have an adaptation process. Medical supervision and medical insurance personnel should first conduct a preliminary medical examination and confirmation of the astronaut's health status, and assist the astronaut in the return module to initially re-adapt to ground gravity, including limb movement, gradual standing adaptation, and supplementation of drinking water and nutrient solution.

"Although the astronauts maintain physical exercise in space, because this flight time is as long as three months, which is the longest space flight time for Chinese astronauts, astronauts will inevitably have muscle atrophy, bone decalcification, and decreased standing endurance, so they need to stay in the cabin for at least 40 minutes." Pang Zhihao said.

This also puts forward requirements for the transfer of astronauts after leaving the capsule. In order to ensure the safety of astronauts and avoid falling down or even fractured bones while walking, astronauts must take a sitting position for all activities after exiting the cabin with the assistance of the staff. "At the beginning of returning to the ground, we should avoid hugging the astronauts, let alone throw astronauts into the air out of excitement." Pang Zhihao said.

After that, the astronauts will enter the physical recovery period of the three stages of medical isolation, medical recuperation and recuperation. Pang Zhihao said that the medical isolation period is about 14 days, during which the astronauts are basically isolated from the outside world; the medical recuperation period is about 20 to 30 days, which can gradually increase the amount of activity; the recovery period is about 3 months, and the astronauts' physiological parameters will return to the pre-flight state, and if the physical condition is good, the astronauts can start normal daily training.

After the astronauts leave the capsule, the on-site staff must also safely handle the return capsule again, such as turning off the power supply of the return capsule, removing the backup unit of the spare pyrotechnic products, removing the γ source of the altimeter, and storing it in a special protective container. Pang Zhihao said that after the return capsule is transported to Beijing, it will also be studied on its return, including ablation, and then it will be placed in the Fifth Academy of China Aerospace Science and Technology Group, which may be exhibited in the future.

It is worth mentioning that the Shenzhou XII return capsule can bring back about 100 kilograms of items from space. Mr. Pang said that after the return capsule arrived in Beijing, it was necessary to remove the items it brought back, such as seeds, experimental samples, hard disks or cameras with photos. In the future, according to the research plans and needs of all parties, experimental samples will be handed over to relevant scientific researchers.

After the evacuation of the Shenzhou 12 flight crew, the Chinese space station will still be running in orbit, and in a few days, it will usher in the Tianzhou-3 cargo spacecraft to receive daily necessities, experimental samples, propellants and other "express packages" from the earth.

Pang Zhihao said that the complete success of the Shenzhou 12 mission not only further verified the functional performance of China's manned space-to-space round-trip transportation system, but also verified the astronauts' long-term stay support technology, as well as the astronauts' ability to complete the out-of-the-cabin activities and extravehicular operations together with the robotic arm, and for the first time tested the search and recovery capabilities of the Dongfeng landing field. "These technological breakthroughs and capability verification can lay a solid foundation for the subsequent construction and application development of the space station, and accumulate valuable experience." (End)

Source: China News Network