Since ancient times, the magnificent Milky Way has been the object of observation and research that people pay close attention to. The ancients didn't know what the Milky Way was, so they imagined it as a river in the sky. As early as the pre-Qin period, the Yellow River and Hanshui River on land were called the Milky Way in the sky, that is, Hehan.

In fact, the Milky Way is a part of the Milky Way and belongs to the solar system. It is named because the bright band whose main part is projected on the celestial sphere is called the Milky Way in China.

Extended data:

The Milky Way contains about150 billion stars and other celestial bodies, 90% of which are stars, and 10% is interstellar matter composed of gas and dust. Viewed from the side, its main part is flat, and 85-90% of the stars are concentrated on a discus-shaped flat sphere. The closer to the center, the greater the density. The shape of a flat sphere is like a disk called a silver disk, and its middle part is called a nuclear ball, and the middle part of the nuclear ball is called a silver core.

Outside the silver disk is a large-scale nearly spherical distribution system. Its low density is called silver halo, the outermost surface has a silver crown, and the material distribution is roughly spherical. The center of the Milky Way is in the direction of Sagittarius, and the Milky Way revolves around it. The sun is an ordinary star in the Milky Way, which is 30,000 light years away from the center of the Milky Way and rotates around its center with a period of about 250 million years.

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