Ecliptic

As seen from the orbiting Earth, the Sun appears to move with respect to the stars. The ecliptic is the yearly path the Sun follows on the celestial sphere. This process repeats itself in a cycle lasting a little over365 days

The ecliptic is the plane of Earth's orbit around the Sun.

The Sun appears to move against the background of stars because the Earth orbits the Sun.

The invariable plane is the average plane of the orbits of the planets. Properly, it is defined as the plane passing through its barycenter (center of mass). The present ecliptic plane is inclined to the invariable plane by about 1.5°.

Ecliptic Media

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  Obliquity of the ecliptic for 20,000 years, from Laskar (1986). Note that the obliquity varies only from 24.2° to 22.5° during this time. The red point represents the year 2000.

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  top view of the plane of the ecliptic (also known as the ecliptic plane) is the plane of the Earth's orbit around the Sun.[1] It is the primary reference plane when describing the position of bodies in the Solar System,[2] with celestial latitude being measured relative to the ecliptic plane.

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  Side view of the plane of the ecliptic (also known as the ecliptic plane) is the plane of the Earth's orbit around the Sun.[1] It is the primary reference plane when describing the position of bodies in the Solar System,[2] with celestial latitude being measured relative to the ecliptic plane.

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  FourPlanetSunset hao annotated

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  The apparent motion of the Sun along the ecliptic (red) as seen on the inside of the celestial sphere. Ecliptic coordinates appear in (red). The celestial equator (blue) and the equatorial coordinates (blue), being inclined to the ecliptic, appear to wobble as the Sun advances.

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  Inclination of the ecliptic over 200,000 years, from Dziobek (1892). This is the inclination to the ecliptic of 101,800 CE. Note that the ecliptic rotates by only about 7° during this time, whereas the celestial equator makes several complete cycles around the ecliptic. The ecliptic is a relatively stable reference compared to the celestial equator.

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  Equirectangular plot of declination vs right ascension of the modern constellations with a dotted line denoting the ecliptic. Constellations are colour-coded by family and year established.