The popular explanation of the ecliptic

The popular explanation of the ecliptic is the apparent trajectory of the sun between stars every year, that is, the intersection of the earth's orbital plane and the celestial sphere.

Ecliptic (astronomical phenomenon)

Ecliptic, noun: Earth's orbit around the sun. Because the earth goes around the sun only once a year and returns to its original position. The route that the sun "walks" in this way is called the ecliptic. Moreover, the orbit of the moon around the earth, that is, the "white road", and the orbits of the planets around the sun are very close to the ecliptic. It is a great circle assumed by the celestial sphere, that is, the projection of the earth's orbit on the celestial sphere. The ecliptic intersects the equatorial plane in vernal equinox and vernal equinox.

Because the earth's rotation axis is not perpendicular to the revolution plane, the equatorial plane of the celestial sphere and the ecliptic plane do not coincide, and the included angle between the two planes is 23 26' 21. (measured in AD 2000), the intersection of two planes connects the vernal equinox and the autumnal equinox. When the earth looks down and the sun changes from south to north, it is called the vernal equinox. A circle from this field to the east, from 0 to 360, is the meridian of the ecliptic, and the angle is called the longitude of the ecliptic. The latitude of the ecliptic is 90 degrees north latitude and 90 degrees south latitude.

Ecliptic (idiom explanation)

In ancient times, astrology was used to calculate good and bad luck, which meant that Qinglong, Tang Ming, Jingui, Tiande, Yutang and Siming Six Days were auspicious gods. When you are on duty on the sixth day, everything goes well and you don't avoid bad luck, which is called "auspicious day in the ecliptic".

The modern ecliptic is a great circle where the earth's orbital plane around the sun intersects with the celestial sphere. Because the earth's orbital motion is attracted by other planets, the moon and other celestial bodies, the position of the ecliptic changes irregularly and continuously in space, but the instantaneous orbital plane always passes through the center of the sun during the change.

This change can be manifested as a slow long-term movement and some short-term changes. People on earth look at the apparent path of the sun between stars in one year, which is the great circle where the earth's orbital plane intersects the celestial sphere. The ecliptic and the celestial equator form an angle of 23 degrees and 26 minutes, intersecting at the vernal equinox and the autumnal equinox. At any moment, the orbital plane that only considers long-term motion is called instantaneous average orbital plane.