Ecliptic coordinate system: Difference between revisions
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The celestial equator and the ecliptic are slowly moving due to perturbing forces on the Earth, therefore the orientation of the primary direction, their intersection at the Northern Hemisphere vernal equinox, is not quite fixed. A slow motion of Earth's axis, precession, causes a slow, continuous turning of the coordinate system westward about the poles of the ecliptic, completing one circuit in about 26,000 years. <ref>[https://en.wikipedia.org/wiki/Ecliptic_coordinate_system Ecliptic Coordinate System]</ref> | The celestial equator and the ecliptic are slowly moving due to perturbing forces on the Earth, therefore the orientation of the primary direction, their intersection at the Northern Hemisphere vernal equinox, is not quite fixed. A slow motion of Earth's axis, precession, causes a slow, continuous turning of the coordinate system westward about the poles of the ecliptic, completing one circuit in about 26,000 years. <ref>[https://en.wikipedia.org/wiki/Ecliptic_coordinate_system Ecliptic Coordinate System]</ref> | ||
==References== | |||
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[[Category: Ascension]] | |||