How is the star shift formed in astronomy?

The stars in the sky are formed by the light reflected or emitted by other planets in the galaxy, and are seen by people after reaching the earth. With the revolution of the earth and the revolution of the solar system, the stars at night will be different at different times and seasons. It also formed the astronomical phenomenon of the stars shifting. Dou generally refers to the Big Dipper, because the Big Dipper can be found in the sky all year round, but its position revolves around the North Star, so it is also used to indicate the passage of time.