When the distance between Tianhe and shenzhou XII spacecraft was about 200 meters, Shenzhou XII switched the display screen to a narrow-vision TV for docking, and as a result, two Tianhe appeared on the display screen, confusing Nie Haisheng who went to space for the third time, obviously he had never encountered this phenomenon, so he directly asked the command center: "There is a ghost here, is it true above, or is it true below?" ”
Suddenly, the live chat room became hot. Some say that it is UFOs, parallel universes, aliens, supernatural beings, and more gods reply: "This has not yet docked, just bring out a small one." ”
Compared with the two Tianhe, the Tianhe above is larger, the outline is more blurred, and the solar sails on both sides cannot be seen. Friends may wish to silently guess in their hearts first: which do you think is more like the truth?
Let's first talk about narrow-sight TV, from the "eight-fold mirror" crosshair and picture on the display screen, it is not difficult to analyze: narrow-sight TV is like the image display of the high-resolution camera in front of the spaceship, not the picture captured directly from the window by the naked eye. The line of sight is the auxiliary line in the docking process, and it is judged whether we are aiming accurately or not.
Figure: Narrow auto control (automatic control)
The three words "narrow self-control" on the screen indicate that it is in a fully automatic control mode, in addition to the speed and direction of the spacecraft, it also includes the parameter settings on the spacecraft such as cameras and screens, and the ghost shadow appears under the parameters of the initial automatic setting.
In the final automatic docking process, it will generally switch to "hand-controlled" mode, just like when the traffic is dense and requires high-precision operation, even if the car is driving in automatic driving mode, your eyes must be staring, holding the steering wheel, ready to intervene at any time.
Astronauts observe the automatic docking situation in real time through the line of sight and the screen, and can immediately carry out manual fine-tuning in case of deviation. "Threading needles" in space is one of the important training programs for astronauts.
Pictured: When docking, the doji on the screen is aligned with the cross sign on the Tianhe
Imagine driving a boat on an endless sea, and two lighthouses appear 200 meters away.
In fact, Shenzhou XII uses more advanced radar and remote sensing technology, so it can easily identify the real Tianhe, and narrow-sightED TV is more for astronaut observation and auxiliary astronaut operations, which will not affect Shenzhou's fully automatic sailing to the real destination.
Pictured: Astronaut manually controlled dimming (effect after 20x acceleration)
Therefore, when Nie Haisheng raised a question, the command center replied: "Beijing understands, please dim the light yourself." So, before reaching the final docking point, the "narrow self-control" on the screen became "narrow hand control", because the astronauts needed to manually intervene to dim the light, and then the spacecraft below the screen gradually disappeared, Nie Haisheng said: There is no ghost this time? After comparison, it was confirmed that the Tianhe number left above was real. Did you guess right?
It is estimated that many photography partners can guess correctly, because this situation often occurs during the photography process, especially when the lens faces strong light or adds filters more frequently, which is called "lens glare" or "glare".
In order to get a high-precision picture, the lens structure is very complex. The picture we took was actually the light passing through the layers of lenses and finally reaching the imaging effect on the sensor. However, if you encounter strong light, such as facing the sun, part of the sunlight will be reflected on the surface of the lens, and when the reflected light is transmitted to the sensor, there will be a "double" on the image.
However, the reflected light is weaker than the "main light", so the doppelganger appears darker than the real body, and because it is reflected, there will be angular shift, inversion, deformation, and smaller.
The docking of Shenzhou XII and Tianhe happened to occur in the "yangzhao area", and the sunlight traveled directly in the vacuum (space), unlike the atmosphere on the earth that filtered and reflected it first, so the sunlight received by Tianhe was very strong. After the Shenzhou XII spacecraft received the strong light reflected by the Tianhe, it was easy to have a "lens glare" situation.
Pictured: True Heaven and No. 1, with a small tail in the lower right
If you look closely, you will find that when the ghost appears on the narrow-sightED TV, the Tianhe below has a "small tail (mechanical arm RMS)" in the upper left, and the real Tianhe "small tail" is in the lower right, indicating that the Tianhe below is actually an inverted doppelganger.
Pictured: The Tianhe number below, with its tail in the upper left
In addition, the light above is stronger and larger, and it can also be judged that the above is true. Of course, judgment is one thing, and convenient observation is more important, so the command center gives instructions for dimming, and reduces glare by adjusting the brightness.
In summary, ghosts have nothing to do with UFOs, parallel universes, aliens, or spirits, nor are they children of Tianhe, which is a very normal optical phenomenon.