Recently, a rare sight has appeared in the Bohai Bay, where several huge ships in the distance at sea level appear to be not on the water, but suspended in the sky. So, how exactly does such a huge ship fight gravity and float in the sky?
First of all, these are ships on the sea, not spaceships, and they can't really fly into the sky. Secondly, there is no evidence that this is a time-space portal or a time-space disorder that allows the ship to cross. To be sure, the ship's real, but levitation is fake.
Some people think that this is because the earth is round, and we see ships far away, which due to the angle causes the illusion of ships floating in the air. But in fact, such a statement must be wrong, and the fact that the earth is round is not used to explain it this way.
Since the Earth is a sphere, this causes the horizon distance we see to be limited, and the things behind the horizon are blocked by the Earth itself and cannot be seen at all. According to the calculation of geometric relations, a person standing on a plane can see the horizon at a distance of about 5 kilometers. If you stand at a height of 50 meters, the horizon distance is 25 kilometers; if the altitude is 100 meters, the horizon distance is 36 kilometers.
If the ship sails off the horizon, we will see the lower half of the ship gradually disappearing, and finally the upper half slowly disappearing. Conversely, if the ship comes toward us from far away on the horizon, we will see the upper half of the ship first, and then the lower half. But in any case, there will be no illusion that the ship is floating in the air.
Others believe that this is a mirage. It should be emphasized that the mirage is not a time-space projection or interlacing, but a rare optical phenomenon. The creation of mirages is related to a significant gradient in air density, as this causes light to be refracted.
Before explaining the cause of the mirage, let's explain why we can see objects. Because the light reflected by the object or the light emitted by the light source carries information into our eyes, after processing by the brain's visual center, we will produce vision and thus see the object.
If the air is very uniform and the density is uniform, then the light travels in a straight line as it travels through this uniform medium. If the temperature and humidity of the lower air are lower and the humidity is greater than that of the upper air, then the density of the lower air will be greater than that of the upper layer, and the refractive index will be greater than that of the upper layer.
Due to the Earth's own obstruction, we cannot see objects behind the horizon. But if we encounter a situation where the density of air gradually decreases from bottom to top, the light reflected by objects far away from the horizon will continue to be deflected downwards, eventually bypassing the curved surface and entering our eyes.
When the human eye sees light, it will always assume that the light travels in a straight line. When we receive the light behind the horizon, it is natural for the brain to make up that the light is coming from a distance along the straight line, so we will see the scenery suspended above the distant horizon, which is a mirage.
Many times, the original view of the mirage is really difficult to find. Because the refracted light is limited, the resolution of the mirage is very low, and the scene is not easy to identify. If it weren't for the iconic scene, it would be hard to know where the original scene was. Of course, there are also mirages that find the original scenery, and the previous Hongze Lake mirage is an example.
Mirages basically occur in the summer, and only when rain and sunlight are abundant can the air have a significant density gradient. The current Bohai Bay is in winter, and there are no corresponding conditions, so the ships floating in the sky are not mirages.
In fact, the ship is not floating in the air at all, but is still floating on the water, which experts say is an optical illusion phenomenon. This phenomenon has occasionally occurred in various parts of the world, because the water near the coastline appears blue, and the meteorological conditions on the far side of the horizon are special, so that the color of the sea water there is lighter than the color of the sky, and it merges into one, resulting in a strange scene of ships floating in the sky.