"Darkness before dawn" means that the night becomes darker before dawn

"Darkness before dawn" means the last darkness before daylight, which is the last darkness before daylight. The darkest time is extended to "the most difficult time before victory" in literature, and also means "the dark forces make their final struggle". The dark forces often struggle most violently and terrifyingly before they are about to be eliminated, so it is said that " The darkness before dawn is the most terrifying."

In a day and night, there is a period of darkness that is particularly dark. This period is the darkness before dawn.

To uncover this mystery, you must first Let’s start with the atmosphere. The earth is surrounded by a thick layer of atmosphere, which is invisible and intangible. However, there are many gas molecules of different sizes, floating dust, etc. in the atmosphere, and the closer to the ground, the more these molecules in the atmosphere The more material there is.

The rotation of the earth brings day and night, and there is always a transition stage between them. Because the sun’s altitude angle is low before sunrise and after sunset, the sun hidden below the horizon shines In the upper atmosphere, various gas molecules and floating dust impurities in the atmosphere scatter light to the ground, so a relatively dark time appears in the sky. In meteorology, the light that reaches the ground before sunrise is called "twilight", and the light that reaches the ground after sunset is called "dawn". The light is called "twilight". The duration of dawn is called "dawn", and the duration of twilight is called "dusk". If there were no dawn and twilight caused by scattering of atmospheric molecules, the alternation of day and night would occur at sunrise and sunset. It happened suddenly at that moment. This situation can be seen on the moon and other planets without an atmosphere.

The "darkness before dawn" is the result of the earth's atmosphere. When the long night When the sun is about to end and the rising sun is about to rise, the sunlight below the horizon shines on the upper atmosphere 2000-3000 kilometers above the earth. When this shines, the scattered light of the sun dilutes the starlight; the upper atmosphere is very thin, and it scatters The sunlight cannot fully penetrate the dense atmosphere and reach the ground. In this way, there is no starlight on the earth, no scattered light from the atmosphere, and no bright sunlight, so it becomes completely dark. Therefore, at this time It is darker than other times of the day.

In fact, at dusk, there is also a dark moment like before dawn, but dusk is the transition from day to night, and the sky should be getting darker. , it’s not as noticeable as when there is a sudden period of darkness when the sky should be bright at dawn.