At around 8 o'clock tonight, the return capsule of the Shenzhou 14 spacecraft was about to return to Earth with the "busiest crew" that had been on a business trip for 183 days. There was previously news that they would use a faster return mode this time, but judging from the report of evacuating space station at 11:01, Shenzhou 14th is still the same as Shenzhou 13th before, using 5 laps fast return mode, which took about 9 hours. In the past, it was flying 11 laps, each lap was about 1.5 hours, totaling about 16.5 hours.
Shenzhou 14 has evacuated the space station
1. Why is the return time of Shenzhou spacecraft longer than that of the United States and Russia?
According to public information, Russia's fastest return record is 3.5 hours, the return time of the US manned "Dragon" spacecraft is 6.5 hours, and the cargo "Dragon" spacecraft can return in 5 and a half hours. We are not comparable to Russia. The fighting nation dares to return directly in a ballistic manner when they are anxious. This is how the Korean female astronaut Lee So-yeon was abolished.
Indian spacecraft dares to land ahead of schedule
Last time, the Tianzhou 5 cargo spacecraft took only more than 2 hours from launch to docking, setting the world's fastest record. When Shenzhou 15 was launched, we had the technology to adopt a shorter docking time, but it was useless in the end. The reason was that manned space safety is greater than the sky, and safer is always more important than faster speed. Similarly, this time the return of Shenzhou Fourteen, we can of course make the crew go home faster, but that will sacrifice safety factors. This is not allowed and more experiments are required to ensure that it is foolproof before use.
manned space flight requires absolute safety
2. Why does Shenzhou 14 return at night?
This time, Shenzhou 14 returns, which is the first night landing in my country's manned spacecraft 19 years, which puts forward more tests on search and rescue. The live broadcast screens at that time are probably not as good as before. Many people asked what was the reason for choosing to return at night this time. It was actually very simple, it just happened to be encountered. Although my country's space station revolves around the earth every 90 minutes, the latitude and longitude of each lane are different. Only this time window tonight is just above the head of the Dongfeng landing field.
Although the space station and spacecraft orbit the earth every 90 minutes, the latitude and longitude of each lap are different
. Although the Shenzhou 14 spacecraft separated at 11:01 noon, it is still on the same orbital plane as the space station, so the landing time is still calculated using the space station location as the model. It is okay to land during the day, but then you have to wait for the space station to turn N circles. It may be a few days later. astronaut has been in space for 183 days, and his heart is like an arrow. The night and the low temperature cannot stop them from going home.
Shenzhou Spacecraft Evacuation Space Station
3. Why does Shenzhou Spacecraft use only one main umbrella when it returns?
In the past, when we watched the picture of Shenzhou spacecraft returning, it finally opened only one main slowdown parachute , and there were 4 American "Dragon" spacecraft. Many people think that ours is not advanced enough based on this. But in fact, the four speed reduction parachutes do have advantages, such as good stability and many backups. It is said that even if one of the speed reduction parachutes of the "Dragon" spacecraft is broken, they can guarantee safe return. However, the disadvantage is that it is easy to wrap around and delay opening the umbrella after it opens. When it returned on November 8 last year, an umbrella of the Dragon spacecraft was not opened for a long time. It is precisely because of this risk that it requires the backup capability to return with 3 umbrellas.
Multiple umbrellas are easy to wrap and delay opening
. The single umbrella mode of Shenzhou Spacecraft is safer. There is no problem of several umbrellas entangling each other. If not, look at the detectors of China and the United States log on to Mars . Do they all use single umbrellas? Of course, the next-generation spacecraft that has already flown for the first time in my country adopts the multi-umbrella mode. It is not that single umbrellas are not good, but that its return capsule is too heavy and has the largest size in the world. With the current materials, single umbrellas cannot hold it, so it can only settle for the second best and use multiple umbrellas.
Single umbrella stability is worse
my country's new generation of manned spacecraft is multi-umbrella
4. Why do Chinese spacecraft use land recycling, while the United States is splashed off at sea?
my country and the Soviet Union landed on land every time, while the American spacecraft basically splashed down at sea. Even the manned spacecraft that India is developing is the first choice to splashed down at sea. Why is there such a difference? Splashing from sea can save the last rocket buffering step in the return capsule, and there is no need to delineate a landing site or evacuate personnel on land. It is indeed an advantage, but it also requires a large number of naval ships and strong maritime search and rescue capabilities. When my country first developed manned space flight, it did not have this capability.
sea splashing must have strong maritime search and rescue capabilities
, and based on the sea area and terrain of our country, the spacecraft return capsule lands at sea, which is easily disturbed by third countries. The situation in the Soviet Union and Russia is similar to ours, so both countries mainly land on land. Of course, this does not mean that "Shenzhou" spacecraft cannot land at sea. In fact, when Chinese astronauts are trained, landing at sea is a necessary subject, and the spacecraft search and rescue system also has sea backups. The new generation of manned spacecraft that has successfully flew for the first time will consider more sea recycling plans because it has the largest return capsule in the world.
0,000 will fall into the high seas, and you have to ensure that everyone dares to touch your return capsule
. Now it is not far from the landing of the Shenzhou 14 return capsule. Let us wish the astronauts a smooth return home. See you at 8 pm.
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