Briefly talk about the process of total solar eclipse in your own words.

Because the moon orbits the earth from west to east, the solar eclipse always starts from the western edge of the sun's circular surface. After the eclipse, sun gear continued to move eastward. An eclipse occurs when the center of the moon wheel and the center of the sun surface are closest to each other. After the birth of light, the surface of the moon continued to be far away from the surface of the sun, and the shadow of the sun gradually decreased. The moment when the western edge of the moon surface is tangent to the eastern edge of the sun surface is called the last contact. At this time, the sun showed a disc shape again, and the whole process of total solar eclipse came to an end.

The total solar eclipse happened because of a magical symmetry. The diameter of the sun is 400 times that of the moon, and its distance from the earth is exactly 400 times that of the moon. Therefore, when the moon is completely between the earth and the sun, for those who are completely in the shadow of the moon, the surface of the sun is completely blocked.

The sun turned black, leaving only a golden halo, and the sky turned indigo. Birds will get lost or fly back to their nests, while bats and other nocturnal animals may come out bleary-eyed.

Extended data

The total solar eclipse is an excellent opportunity for people to know the sun. The sun you usually see is only its photosphere, and two important levels of the solar atmosphere outside the photosphere-chromosphere and corona-are submerged in the bright brilliance of the photosphere.

Chromosphere is the middle layer in the solar atmosphere, about 2000 kilometers thick above the photosphere; Outside the sun, it is surrounded by extremely high temperature (millions of degrees Celsius) but very thin plasma, and the range of plasma is several times larger than the sun itself. This is called the corona.

The brightness of the corona is only one millionth of that of the sun itself. Usually, it is completely hidden in the blue sky caused by scattered light from the earth's atmosphere. During the total solar eclipse, the moon blocked the spherical surface of the sun, and red balls and silver corona appeared one after another on the dark sky background. Scientists can observe the chromosphere and corona at this specific time and under specific conditions, and take photos and spectrograms of the chromosphere and corona, so as to study the physical state and chemical composition of the sun.

For example, when French astronomer Janssen observed the total solar eclipse on August 1868, he photographed the spectrum of solar bait and discovered a new element "helium", which was discovered on the earth by British chemist Remus more than 20 years later.