What is the ecliptic?

Zodiac: Astronomy refers to the track of the sun's annual apparent motion on the celestial sphere, that is, the great circle of the sun's apparent path in the sky as the "ecliptic", that is, the projection of the earth's orbital plane on the celestial sphere.

Celestial sphere: an imaginary sphere with the center of the earth's sphere as the center and a large radius. In imagination, all celestial bodies are attached to the celestial sphere.

Zodiac: The sun runs from west to east on the ecliptic, and it goes around for one week every year. There are twelve constellations on a belt on both sides of the ecliptic. They are Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius and Pisces. People on earth can see them one after another in a year.