Recently, China Aerospace announced the accuracy of the landing point of Shenzhou 13, which is incredibly accurate, because the actual landing coordinates and the fourth predicted landing coordinates are only 130 meters apart, which is actually more accurate than the bullseye of the air pistol athlete hitting 10 meters away.
Why? Because the Shenzhou 13 spacecraft departed from a 400-kilometer-high orbit around the earth, after multiple rounds of orbital braking, the return capsule was separated from the propulsion capsule at an altitude of 140 kilometers, so the return capsule without a propulsion system hit the Dongfeng landing field on the ground from 140 kilometers away.
Finally, the actual landing point of the return capsule and the predicted landing point coordinate error is only 130 meters, why is it more intelligent than the United States? So let's talk about it.
Shenzhou 13 used the fast return technology for the first time, only 5 circles around the earth, shortened by nearly 20 hours, so that the Shenzhou 13 astronauts are much more comfortable, less guilty, which shows that China's space technology is constantly learning and progress, there is a tendency to catch up with the United States and Russia.
Dongfeng landing field is the largest spacecraft landing site on the mainland, about 20,000 square kilometers, very vast, but the predetermined core landing point of the Shenzhou 13 return capsule is a 36×36 kilometers of square-shaped area, which is the target of the Shenzhou 13 return capsule, and the bullseye is the predicted landing coordinates.
We divide the 36×36 km "target" into 10 rings like the air pistol target, each ring is 3.6 km wide, then the 10th ring in the center is 3.6 km in diameter and 1.8 km in radius, as long as the actual landing point of the return capsule is 1.8 km away from the center of the "target", it is a 10-ring target performance.
However, the actual landing point of the return capsule and the predicted landing point coordinate error is only 130 meters, which can be regarded as a target performance of 10.8 rings, which is very good, because the return capsule shoots from a height of 140 kilometers to the ground, there is great uncertainty, because it is not a straight line target, nor a fixed target.
Return capsule return, The China Flight Control Center needs to accurately calculate many factors, the earth's rotation speed, wind speed, return capsule speed, atmospheric drag strength, etc., processing these data to obtain the predicted landing point coordinates.
It should be known that while the return capsule is flying, the earth is also constantly rotating from west to east, so when calculating the coordinates of the predicted landing point, the speed of the return capsule and the rotation speed of the earth must be taken into account, the return capsule is a cylinder, and its resistance in the atmosphere will also affect the accuracy of the landing point.
When the return capsule leaves the "black barrier area" for about 5 minutes, the main parachute is opened, and the return capsule is hung in the main parachute with the wind, how big the wind speed is, it will naturally affect the landing point of the return capsule, so this should also be taken into account. Therefore, the error of 130 meters is very accurate.
In contrast, in the United States, the actual landing point and the predicted landing point error is much larger than 130 meters, and in the last century, when Armstrong returned with the Gemini 8 spacecraft, the error reached 800 kilometers, quite a small half earth, which is really outrageous.
This is already what happened in the last century, take the current Return of the American Dragon spacecraft, I have watched the return of the American Manned Dragon spacecraft many times, in fact, it is not so accurate, they are landing the return capsule into the ocean, waiting for the salvage of the ship, the way is different from mine, but the landing point is absolutely not as accurate as the Shenzhou 13 return capsule.
This also proves that some of the technologies of the Chinese space station technology and manned spacecraft technology on the mainland are already more sophisticated than the technology of the US space station, but the United States does not recognize it, and we do not need to explain it.
The accurate target shooting of the Shenzhou spacecraft reflects the world-class aerospace technology of the mainland, but there are still improvements in the return time of the spacecraft, the Russian Soyuz spacecraft only took 4 hours to return to the whole process, while the Shenzhou 13 spacecraft returned in 9 hours, and the problem lies in the number of orbits.
When the Shenzhou 13 spacecraft returned, it circled the earth for 5 times, a circle of about 90 minutes, which took more than 7 hours at once, and the Russian Soyuz spacecraft began to brake around 1 and a half times. If the Continental Shenzhou spacecraft can reduce the circumference from 5 to 3 laps, the return time can be greatly shortened, and 9 hours will become 6 hours.
Of course, the reduction of 5 laps to 3 laps greatly increases the technical difficulty, because every time the manned spacecraft circles the earth, there is only a very short chance to return, probably only a few seconds, accidentally missed to go can only wait for the next lap, around 5 laps there are 5 chances, around 3 laps means only 3 chances.
In short, the Shenzhou 13 return capsule shot targets from 140 kilometers away, the error is only 130 meters, which is a 10.8 ring performance, which belongs to the accurate target shooting, in fact, it is more advanced than the US space station technology. Interesting and informative scientific content, please pay attention to the only WeChat public account: Interesting Exploration