Shenzhou XII landed successfully! How are the three astronauts doing? Do they still need to be quarantined?

Expert of this article: Liu Yan, Space Application Engineering and Technology Center, Chinese Academy of Sciences

Do you remember the day when the "space trio" left the ground?

"Throw the heat-resistant outsole!"

"The return capsule is hanging!"

"Reverse thrust engines!"

…

At around 13:30 on September 17, the Shenzhou XII manned spacecraft's return capsule reverse thrust engine was successfully ignited and landed safely in the designated area of ​​the Dongfeng landing site.

It is reported that this is the first time that the Shenzhou spacecraft has landed at the Dongfeng landing site. The door of the Shenzhou XII return capsule was opened, and the medical staff confirmed that the three astronauts were in good condition.

The three-member crew worked on a business trip in space for 90 days. Before returning, they completed tasks such as the transfer of cargo spacecraft materials, management of the Tianhe core module assembly, operation of the large robotic arm, carried out two extravehicular activities, and performed space science experimental tasks in multiple fields.

What preparations need to be made before the return trip? How many steps need to be completed on the return trip? When is the next launch?

What preparations should be made before returning?

Work Closure: Inspection, Evacuation, Cleaning

Before separating from the core module, the astronaut crew completed various preparations for return with the support of ground personnel.

The space station is a space hotel, and it is necessary to sort out and inventory the supplies and items in the station.

In addition, in order to facilitate the check-in of subsequent passengers, save space and meet the needs of mission support, it is necessary to do a thorough cleaning and remove the garbage, put them into garbage bags and put them into the orbital module, allowing them to fall into the atmosphere and be destroyed along with the orbital module.

Before returning, it is also necessary to check the status of related equipment and products, including the air tightness check of the cabin pressure suit and the air tightness check of the communication headband, etc. This is very important for the protective equipment used for future return.

After all inspections were completed, the doors of the cargo ship, core module and node module were closed, and we entered the Shenzhou XII and changed into the cabin pressure suits.

Packaging and fixing

The crew members turned into packers, storing, binding and securing items in the return capsule, because the impact of turbulence and speed changes during return is very large. If the binding does not meet the requirements, not only will the items be damaged, but it may also cause unpredictable interference to the flight mission.

The astronauts' return luggage and scientific experiment samples, including urine, saliva and other samples, must be brought back to the ground for analysis.

▲ Nie Haisheng demonstrates his physical preparation for cycling in space

Strengthen physical exercise, train muscles, bones, heart and lungs, and prepare for return and landing and readaptation.

How many steps are needed to return to the ground?

The general steps of the return journey include: braking, taxiing, re-entry, landing, and search and rescue.

The Shenzhou manned spacecraft consists of three parts: the orbital module, the propulsion module and the return module.

During the spacecraft's return process, it first separates from the orbital module. Then the return module and propulsion module use reverse thrust to slow down, change the spacecraft's attitude, and enter a trajectory back to Earth. The attitude adjustment controls the return landing point range to a certain extent.

▲The propulsion module and the return module have been separated

Afterwards, the return capsule separated from the propulsion capsule, and the return capsule returned to the ground with three astronauts.

When the spacecraft reenters the Earth's atmosphere, it is so fast that it rubs against the atmosphere and turns into a flashing fireball. A plasma gas layer is formed around it, shielding electromagnetic waves and forming a "black barrier", which temporarily causes the return capsule to lose contact with the ground. The "black barrier" disappears at an altitude of about 40 kilometers from the surface, and the return capsule can regain contact with the ground.

▲The return capsule enters the "black barrier zone"

Next comes the recovery and landing phase.

When the return capsule is about 10 kilometers away from the earth, the recovery and landing operation begins. The parachute is opened and the heat-resistant bottom of the return capsule is discarded. When it is about 1 meter away from the ground, the reverse thrust engine is ignited to ensure a soft landing of the return capsule and to ensure the safety of the astronauts to the greatest extent possible.

After the return capsule lands safely, its positioning system starts working, indicating its location so that the search and rescue system can find the target in time, improving the reliability and effectiveness of the rescue.

Why choose the Dongfeng landing site?

This is also the first time that astronauts have returned from space at the Dongfeng landing site.

The reason for landing at the Dongfeng landing site is that the Dongfeng landing site is larger than the Siziwangqi landing site. After mastering the desert search and rescue technology, the Dongfeng landing site has the advantage of vast area and sparse population, and has a higher safety factor.

▲Dongfeng Landing Site of Jiuquan Satellite Launch Center (Photographers: Dong Yanrong, Jia Tiange, Wang Zhen, Hu Yi)

The Dongfeng landing site system has completed three full-system search and recovery comprehensive drills, and has carried out multiple search and rescue, field survival and other training targeting the complex and special terrain of the landing area.

my country generally adopts the mode of "searching and rescuing astronauts in the air and disposing of the return capsule on the ground", which can achieve "fast positioning, fast arrival, and safe exit from the capsule". After the return capsule arrives on the ground, the search and rescue system will immediately determine the location and rush to the landing point.

▲The air search and rescue recovery team arrived at the designated area

Do I still need to be quarantined after I come back?

When they first land, space medicine experts will provide medical supervision and medical support to the astronauts, based on samples of urine, saliva, etc. collected from the astronauts while they are in orbit.

The most obvious feeling the astronauts feel after returning is the discomfort caused by the long-term weightlessness environment. The Astronaut Center has prepared a more targeted recovery plan for the astronauts.

Physical recovery is divided into three stages: medical isolation period, medical convalescence period and recovery and convalescence period.

Phase 1: Medical Isolation

For about three to four weeks, according to the three-level isolation system, the astronauts will be basically isolated from the outside world.

Astronauts will get enough rest and dietary nutrition, and then they can moderately move their upper limbs to promote the redistribution of body fluids, improve cardiovascular regulation function, and carry out relevant physical therapy, health care, and physical and mental conditioning.

Astronauts need to adapt to the Earth's gravity environment, improve the cardiovascular system and support the function of motor organs, improve standing endurance, and eliminate post-flight fatigue. Astronauts will also receive massage or some progressive exercises to restore their physical and mental state.

Phase 2: Medical convalescence

This phase will last about 20 to 30 days.

The astronauts will stay in a sanatorium with good weather and air, and gradually increase their activity while continuing to recover.

Phase 3: Recovery and convalescence

This stage lasts about 3 months.

The astronauts' physiological parameters will be restored to their pre-flight state. If they are in good physical condition after three months, they will begin normal daily training.

When is the next time you go?

Shenzhou XII has just returned, and Tianzhou 3 is taking over.

According to the manned space flight engineering office, Tianzhou 3 is ready to go and will be launched in the near future. After that, Shenzhou 13 is expected to be launched in October, when three astronauts are scheduled to stay in orbit for six months. The high density of launch missions has made space busy.

Mid-Autumn Festival is approaching

After returning to Earth

What do the three astronauts want to eat most?

The three gave different answers:

Nie Haisheng most wanted to eat Xiangyang's beef offal noodles

Liu Boming's favorite dish is the purple beans from his hometown.

What Tang Hongbo wants to eat most is watermelon

Besides this

The 17th is also the birthday of astronaut Liu Boming

Welcome the heroes back

I also wish Liu Boming a happy birthday!