please explain this video.
I am supposing that is early morning. It is quite dark on the ground.
The video seems real but it could be a spoof by somebody who is familiar with the region who is filming this real event.
The line looks like it could be created by the morning Sun being obscured by a mountain range where the video maker has positioned themselves either by accident or design so the shot is divided in two so there is a line between them, the mountain range and the Sun. Usually when you see that kind of thing the line is at an angle and you are not under it. The aircraft 'dissapearing' is just going from sunlight to shadow.
You can see at the beginning of the video the shadow is rotated slightly clockwise compared to at the end when it is slightly anticlockwise. Presumably you could calculate how far away the mountain range using that change. The shadow seems to be moving in the correct direction for it being a shadow where the sun is moving to the right in the northern hemisphere. Sun goes right shadow moves left.
Probably you can find other videos of something similar but without having the video maker in that exact same position.
Probably if an American expert was asked they can tell us where the shot was taken and when that effect can be seen at that location. It would only happen there on a few days per year because the sun is never in the same position each day.
So my bet is you have a fairly distant but very high mountain or mountain range and the shadow of the mountain appears on the left side.
It is fairly common to see the shadow of the land travel through the sky fairly quickly when the sun sets on flat land here in Finland, so this is similar but at right angles so the shadow moves much more slowly.
Something somewhat similar here but very cool picture. "moon rising through the immense shadow of Hawaii's Mauna Kea volcano."
And again the moon is more obvious because the Sun is shining on it
