# precession of the equinoxes

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## precession of the equinoxes

n.
A slow westward shift of the equinoxes along the plane of the ecliptic, resulting from precession of the earth's axis of rotation, and causing the equinoxes to occur earlier each sidereal year. The precession of the equinoxes occurs at a rate of 50.27 seconds of arc a year; a complete precession requires 25,800 years.

## precession of the equinoxes

n
(Astronomy) the slightly earlier occurrence of the equinoxes each year due to the slow continuous westward shift of the equinoctial points along the ecliptic by 50 seconds of arc per year. It is caused by the precession of the earth's axis around the ecliptic pole, with a period of 25 800 years

## preces′sion of the e′quinoxes

n.
the earlier occurrence of the equinoxes in each successive sidereal year.
[1615–25]
ThesaurusAntonymsRelated WordsSynonymsLegend:
 Noun 1 precession of the equinoxes - a slow westward shift of the equinoxes along the plane of the ecliptic caused by precession of the Earth's axis of rotationnatural action, natural process, action, activity - a process existing in or produced by nature (rather than by the intent of human beings); "the action of natural forces"; "volcanic activity"
References in periodicals archive ?
The phenomenon, known as precession of the equinoxes, is caused by the gradual shift of Earth's rotational axis.
'Muslim scholars calculated the angle of the ecliptic; measured the size of the Earth; calculated the precession of the equinoxes; explained, in the field of optics and physics, such phenomena as refraction of light, gravity, capillary attraction, and twilight; and developed observatories for the empirical study of heavenly bodies.
Both the canvas and the carving, depict the axial precession of the equinoxes, where both the north and south poles move in a circular direction, taking 25,772 years to do a full circuit of 360 degrees.
* the precession of the equinoxes with period of 25.8 ka;
Chapter 8 "Cold Times" summarizes our knowledge about the Pleistocene Ice Age in the light of the following: geochemical and sedimentological clues in deep-sea sediments; plate-tectonic driven reconfiguration of continents and associated oceanic circulation patterns; alteration of precipitation patterns and albedo; distribution of glacial deposits; the periodicities of precession of the equinoxes, obliquity of Earth's rotational axis, and eccentricity of Earth's orbit; changes in solar insolation; variation in seawater paleo-temperatures determined from oxygen isotope ratios of fossil shells and glacial ice; and concentrations of atmospheric greenhouse gases preserved in ice-trapped bubbles.
Astrology begins to recede from the center of intellectual life by the late seventeenth century, perhaps not only because of the accumulation of scientific evidence, which had already begun (as Hubner reminds us) with the ancient astronomers' observation of the precession of the equinoxes, but more particularly because of the emergence of a scientific method whereby astrological hypotheses could no longer appear to constitute true knowledge.
17 The fifth brightest star in the sky will become the North Pole Star in about 14,000 years due to precession of the equinoxes - what is its name?

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