What is red elf lightning? How is it formed?

We have all seen lightning. White lightning that appears in the clouds on rainy days is very common, but it is actually only one kind of lightning. For example, there is a kind of lightning called red elf, which most people have never seen.

The red elf was first discovered in 1886, but there is no clear data to prove its relationship with thunderstorms and lightning. Until1July 6th, 989, John R (John R), then professor of physics at Minnesota Comprehensive University, recorded the jumping flame with a low-light camera. During the playback, he and his two graduate students, Robert Franz and Robert Nemzek, were surprised to find two giant flashes in the sky in northern Minnesota. Later, they quickly proved that the Red Elf was a special kind of lightning above Lei Yun, and unveiled the mystery of the Red Elf for nearly a century.

What exactly is a "red elf"

This is because the red color in lightning comes from nitrogen molecules in the atmosphere in the red band of 600 to 700 nanometers, and it also emits under the blue light wave of 300 to 400 nanometers, but the intensity is low. Although they are both red and blue, most of what we see is red because of the efficiency of light propagation and the recognition ability of the naked eye. In addition, the occurrence time is less than 1/30 seconds, and the direction of occurrence is difficult to predict, so this lightning is named "Red Elf".

Red elf is a kind of high-altitude atmospheric discharge phenomenon accompanied by thunderstorm, which usually occurs at the top of thunderstorm cloud about 30 to 90 kilometers from the ground. The upper part of the red elf is red, and the bottom gradually turns blue. The width is about five to ten kilometers, the duration is about ten to one hundred milliseconds, and it is as fleeting as lightning.

Although known as the "red elf", this lightning is not red as a whole. It is divided into two parts:

The top is a columnar or beam-shaped light-emitting area, which is generally red, and the top continues to extend downward, reaching a height of 70 kilometers; The bottom gradually becomes a blue curly filiform structure, like a hanging ribbon, with a width of 5 km to 10 km, which can extend down to an altitude of 40 km.

Elves are divided into three categories: rings, DC jets and jellyfish, all of which are the result of electromagnetic waves generated by lightning strikes. Most of them are red, but their tentacles will turn blue. Like most luminescence phenomena, the main elements that exist determine the color. Nitrogen produces red and blue, which are the main elements for the formation of red elves.

The red-orange color is caused by the sudden acceleration of heavy electrons in the middle layer. When electrons collide with nitrogen molecules, their rapid movement produces heat, ionization and red light.

So, how is the red elf lightning formed?

Red elf lightning is a short-lived luminous event. It is a group of high-level atmospheric luminescence phenomena that only occur at very high altitude. They are mainly related to thunderstorms and cumulonimbus clouds.

Lightning comes from a large number of positive charges accumulated at the top of clouds, so after lightning occurs, the ionosphere and the top of the layer will generate a strong electric field, attracting electrons to move upward. In the process of movement, it will collide with gas molecules. For example, if the generated electric field is strong enough and the surrounding air is thin enough, electrons can obtain a fairly high amount before colliding with air molecules. When an electron collides with an air molecule, it will hit an excited state, making the molecule emit light, resulting in a high transient luminescence phenomenon of the red elf.

Theoretically, this phenomenon occurs at an altitude of 40 to 90 kilometers. The brightest red elf can be seen by the naked eye, but it has been unknown for a long time. The reason is that it happened after extremely bright clouds and lightning. The luminous time of the red elf is usually less than one thirtieth of a second, and it is usually not very bright, so the probability of its appearance is quite low. Therefore, scientists must use a highly sensitive camera to continuously record the lightning in the sky in order to record this short-lived high-altitude luminous phenomenon.

Because this natural phenomenon is still in the stage of scientific research, it is necessary to continuously collect and sort out relevant data and information. At present, there is not enough evidence to prove that the accident or fault is caused by it. As for its other effects on human beings, further scientific research and demonstration are needed.