The apparent position of the Sun

The apparent position of the Sun - The spring equinox, seen...

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The apparent position of the Sun along the Ecliptic shifts almost a degree every day Note that a circle has 360º. This is a relic of Babylonian estimates for the length of a year. The Earth’s axis precesses (wobbles) like a top, once about every 26,000 years. Precession changes the positions in the sky of the celestial poles and the equinoxes. Polaris won't always be the north star.
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Unformatted text preview: The spring equinox, seen by ancient Greeks in Aries, moves westward and is now in Pisces! Lunar Motion Phases of the Moons 29.5 day cycle new crescent first quarter gibbous ^waxing Full gibbous last quarter crescent ^waning Eclipses recur in the approx. 18 yr, 11 1/3 day saros cycle But even then, eclipse location and type (e.g., partial, total) may vary...
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The apparent position of the Sun - The spring equinox, seen...

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