Recently, a friend in Gansu was photographing sunrise by the lake, accidentally photographed a huge luminous UFO. The UFO emitted a huge white light, dragging its long tail, like a tadpole.

Recently, a friend in Gansu was photographing sunrise by the lake, accidentally photographing a huge luminous UFO. The UFO emitted a huge white light, dragging its long tail, like a tadpole.

According to the video taken by , this should be the wake generated by the rocket launch.

rocket wake is a high-temperature and high-speed gas generated after the rocket propellant is burned. After the tail nozzle , it has a complex wave system structure, including the inner jet and the outer jet, and the boundary layer. The inner jet is a high-temperature and high-speed chemical reaction product generated by fuel combustion, while the outer jet is a low-temperature and low-speed mixture gas.

So how do the snake-shaped tails at the distal end of the smoke clouds form? This is because the wake contains a large number of aluminum trioxide particles. These particles with relatively small particle sizes are sprayed out by the nozzle and suffer less resistance in the upper atmosphere , so they can last for several kilometers. Due to the circulating airflow between the stratosphere and the intermediate layer, the distal end of the rocket flow field is highly instable to mix with the air, so the tail is blown into a spiral shape.

In fact, there are a large number of "smoke clouds" with different complex structures behind the wake. When the rocket engine type, propellant type and flight environment are different, the "smoke cloud" of the rocket wake will show different sizes and structures.

The reason why emits huge white light is related to the " Twilight Effect". The so-called "twilight effect" refers to the condensation tail left in the atmosphere after the launch vehicle of various spacecraft such as missile , rockets and other spacecraft after it is launched, and the condensation tail left in the atmosphere after the fuel is burned, which is observed by the ground under special light conditions.

The rocket spacecraft's condensation tail , with an altitude of 80 to 100 kilometers. When night falls, the lower layer has entered the night, and the sun can still be illuminated by the high altitude. Therefore, when the rocket rises in the night sky, it gradually leaves the shadow area of the earth. The rocket's tail will be illuminated by the high altitude sunlight. For observers on the ground, although the sky is dark, the illuminated rocket trails are particularly conspicuous. As the rocket flies higher and higher, the atmospheric pressure gradually decreases, the tail diffuses become wider and wider, and becomes a special shape under the action of high air flow. This phenomenon of is also called "Twilight Effect".

is judged to be the wake of the rocket launch, rather than the trajectory generated by the missile launch, because the rocket trajectory is mostly flying upward to a height, and the visible wake time will last three or four minutes. In comparison, the active section flight time of the ballistic missile is about two minutes, which is short, and its trajectory is not completely upward, but is flying vertically upward for about two minutes before performing a program turn in the target direction. Therefore, the tail flame disappears very quickly, and the time to see the tail flame is very short. If it is in bad weather or low visibility, the tail flame will soon be unseen. The passive segment of the missile basically relies on inertia to fly, usually without power, so the tail flame is even less visible.

This huge luminous UFO seen in Gansu was also discovered by netizens in Fuhai County, Xinjiang on September 21, and the shape was similar to that found in Gansu. Finally, it was discovered that it was a wake generated by the engine of the Russian "Soviet MS-22" manned spacecraft that went to International Space Station on the 21st Beijing time.

These situations are actually very common. , the "white dove" that flies over the night sky, is formed after the tail of a solid fuel missile is twisted and floated in the air after the test launch.

and the following mushroom cloud that is constantly expanding. In the photo, the shiny part is the result of the unburned booster particles and water molecules contained in the rocket's exhaust gas, which are released in the lower density atmosphere of the higher layer after being compressed and cooled.

The yellowish-brown sky left by the sunset greatly renders the color effect of the tail head, and the low end of the tail, located below the sunset line, is faintly illuminated by the full moon.Before the sun sets, under the sunlight, the bright and rainbow-colored clouds at the tip of the trail are formed by high-altitude ice crystals in the flame plume during the rocket separation stage.