Our planet Earth not only spins, it wobbles, in part due to the gravitational effects of the Sun and the Moon and the other heavenly bodies upon it. Earth is tilted about 23.5 degrees from the true vertical (90*), and goes 'round the Sun at an angle of about 66.5 degrees. This two-thirds tilt, combined with the not-quite circular orbit of the Earth results in the Earth having seasons (the orbital "eccentricity" of the Earth, its difference from a true circle to an ovoid, is 0.02%, which is why the Earth takes 365.25 days to go around the Sun, and not just 360 days). The whopping difference of 0.02% adds up to about three million miles in about 584 million, the total length of Earth's orbit. Still, that paltry three million miles makes a difference. The Earth moves through space fastest in January, when it is closest to the Sun, and slowest in June, when it is farthest, and the difference totals out to about 7.7 minutes.
The wobble is called "precession" and precession is a remnant effect of Gaia's collision with Theia, the four billion year old calamity that gave birth to the Earth and the Moon. The Moon's gravity has acted as a brake, causing precession to slow from the exaggerated motion of a gyroscope to a much more leisurely swaying that goes full circle in about 25,772 years.
As a practical matter, that means that every few thousand years our Pole Star changes. In 3000 BCE, the star Thuban was the Pole Star. Thuban, an inconspicuous fourth magnitude star, can now barely be seen in Earth's light-polluted skies. In 1000 BCE, the Pole had shifted so that it pointed (more or less) at the star Kochab, which got its name because it was "The Star," Kochba in Hebrew (although it was never so aligned that everyone called it the Pole Star; ancient Roman astronomers ignored it).
Familiar Polaris became the Pole Star around 400 CE; at present, the Pole is drifting closer to it, and Polaris and the Pole will be perfectly aligned at 90 degrees in the year 2100. The Pole will then drift away from Polaris toward the star Errai, which will be the Pole Star in the years surrounding 3000 CE. Eventually, Deneb will be our Pole Star in 10,000 CE, and Vega in 14,000 CE. After Vega's time, the Pole will begin shifting back toward Polaris, which will be the Pole Star again in 27,800 CE. I can't wait!
The wobble also means that the seasons shift slowly over time, which is why the process is called "Precession of The Equinoxes". Actually, the seasons themselves don't shift as much as the First Point of Aries (equivalent to the first day of Spring) shifts relative to the Zodiacal constellations. The action is called Precession (as opposed to Procession) since the First Point of Aries appears to move backwards through the constellations of the Zodiac. In astronomy, a precession cycle is called a "Platonic Year"; in astrology, it is called a "Great Year."
Human history is an absurdly short affair in terms of cosmological time. Were we to boil down the 14 billion year old universe to a two week long event, Earth would have appeared just four days ago. The dinosaurs would have ruled the Earth just three hours ago. And the sweep of written human history would be just six minutes old. The Trinity Test and the Moon landing would have occurred two virtually indistinguishable fractions of a second ago.
The Lascaux cave paintings are just one Great Year old, and the earliest writings of which we know barely look back earlier than a time when the Spring Equinox was in Gemini. The first astronomical / astrological records coincide with a time when the Sun entered Aries on March 21st, and we haven't even quite precessed through the entire constellation of Pisces yet.
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