Text: Crocodile entertainment begonia
Edited by Ming Qiao
preface
"Shenzhou 19, welcome home!" This was originally the ending of the "space blockbuster" that the people of the whole country were looking forward to on April 29, but a sudden windy sandstorm made the astronauts' return plan press the pause button.
The return mission, which was originally scheduled to be carried out on April 29, was forced to be postponed due to the sudden windy and dusty weather at the easterly landing site in Ejinaqi, Alxa League, Inner Mongolia, where the average wind speed exceeded level 6 and the visibility plummeted.
The relevant departments also gave a reasonable explanation for this, strong wind weather will affect the attitude of the parachute open, and even make the return capsule deviate from the predetermined landing site, and the severe sand and dust will block the communication signal, making the search and rescue more difficult.
And this attitude of "preferring to postpone rather than take risks" is the confidence of China's "zero mistakes" in aerospace.
Just 48 hours ago, the last system-wide exercise had just been completed at the landing site, with nearly 100 vehicles assembled, five helicopters on standby, and a satellite communications detachment ready to transmit back the first picture of the astronauts' successful return to the ground within the "golden 10 minutes."
But no one thought that just when everything was ready, the local weather would become the biggest "roadblock".
In the face of this sudden meteorological crisis, the command of the landing site also held an emergency overnight meeting.
According to relevant sources, the safe return of the spacecraft needs to meet the hard indicator of "average wind speed ≤ 15 m/s", and the measured wind speed on that day has exceeded the standard, which is one of the main reasons for the delay of this return.
To add insult to injury, the end of April coincides with the high winds in the region, so the dust can last for several days.
In the past, most of the Shenzhou spacecraft would choose to land in the western area with flat terrain, but in order to avoid bad weather, the team decided to use the larger eastern area.
However, it is full of saxony forests, saline-alkali lands and wetlands, and it is difficult for vehicles to pass, but our aerospace command team has also thought of this in advance, and the relevant search and rescue team has been practicing complex terrain rescue in the local area a month in advance to ensure that "where to fall, there is no mistake".
The spacecraft needs to accurately match the transit time of the space station and the weather at the landing site, and the researchers finally locked an optimal landing time window based on repeated calculations of orbital parameters - the wind weakens at this time, and the spacecraft can complete the whole process from separation to landing in 50 minutes in the "5 laps of rapid return" mode.
Seeing this, you may have a question in your heart, that is, in this 13,000 square kilometers of uninhabited area with no network signal, how can we ensure that this search and rescue operation is foolproof? In fact, the answer lies in the two "special forces".
The first thing to escort the astronauts is our satellite communications detachment, which arrives at the landing site at the same time as the capsule opener, carrying portable satellite communication equipment and quickly assembling antennas, hosts, and cameras like building blocks.
In less than 10 minutes, they were able to smoothly transmit the scene back to the Beijing command center.
The other is our TT&C team, which is known as the "Gobi Sky Eye", which uses an upgraded version of the equipment to lock the return capsule with the accuracy of "seeing hair from 100 meters away", providing the last layer of vital guarantee for the return home.
However, it is worth mentioning that the most amazing thing about this return trip is the practical application of the "5 laps of fast return" technology in the mainland's aerospace industry.
Let's explain this concept more vividly, if the earth is compared to a playground, then the previous spacecraft is like a novice who has just learned to drive, and it takes more than a dozen turns on the playground to find the exit, while the current Shenzhou spacecraft is more like an old driver, who can quickly find the right time to rush out with one foot on the accelerator.
This time, the spacecraft returned home, from leaving the space station to landing, the whole process took only 50 minutes.
What is this concept, you must know that in the early days when the Shenzhou spacecraft returned to the ground, it took a full 24 hours to land smoothly.
And now it takes less than 24 times the time it used to be, which is equivalent to taking a train to Beijing to Shanghai, but now it has been changed to a plane.
Behind this technological breakthrough is the precise positioning of the continental Beidou navigation system, the real-time orbit calculation of intelligent algorithms, and the millimeter-level attitude adjustment of the thruster, which is the great breakthrough of this new technology.
However, the most exciting part is when crossing the "black barrier area", when the return capsule is 7 per second. When it rushed into the atmosphere at a speed of 9 kilometers, the temperature on the surface of the spacecraft instantly soared to more than 1,500 °C, causing a "wall of fire" of plasma to form around it.
At this time, the spacecraft will temporarily lose contact with the ground for about 4 minutes, if this matter was put in the past, we can only pray for the good luck of the astronauts, but now we have another powerful black technology - quantum communication relay system.
This powerful technology allows the spacecraft to maintain contact with the ground in the high temperature after entering the atmosphere, and the safe landing of the spacecraft is very reassuring.
In this thrilling 48 hours, what really moved people was not the technical parameters, but the ordinary people who were silently dedicated.
In the accusation hall of the Jiuquan Satellite Launch Center, the engineers and scientists have been sticking to their posts, closely staring at the changes in the weather on the screen and the position of the spacecraft, and the other astronauts have not been idle, and in these forty-eight hours, they have really done everything.
Behind everything is their silent dedication and dedication, and let us pay high tribute not only to those aerospace heroes, but also to those aerospace workers who are silently working behind the scenes, they are the backbone of the mainland's aerospace industry.
In addition, in contrast, the US "Starliner" spacecraft once caused a catastrophe due to an air leak, but the "double insurance" strategy of the mainland aerospace is more stable, and this is the secret of the extremely low error rate of the mainland aerospace.
I believe that everyone will be like me when watching the live broadcast of the spacecraft's return, the palms of their hands are full of sweat, and every time the spacecraft lands smoothly, their hearts are full of excitement and pride, and they will be proud of the strength of the motherland's science and technology!
For these astronauts who are silently working behind the scenes, what they have to do is to practice "safety is not a probability, it is 100% that must be achieved." This sentence.
From Shen 5 to Shen 19, 22 years of manned spaceflight, China has perfectly interpreted the awe of life with "zero mistakes".
And these 48 hours of twists and turns, I believe that it will eventually be won, which is also the best footnote to this awe.