The precession movement

The small star which shines in the middle of one's window is the one which nowadays coincides (almost) with the celestial North. This circumstance has made it receive the name "Polaris". The Arabs knew it as Al Kaukab al Shamalty (the northern star), while Chinese astronomers baptized it as Han Tien Sang Ti (Supreme Prince of the North). The light we see from it, corresponds to the time when Juan Sebastian Elcano was about to sail around our world for the first time. As the geographic North is in the same direction, we often use it as a reference point for nocturne positioning.

However, the earth has a swinging movement (precession). This swinging movement makes the north point at different stars. The displacement is very slow and 25,780 years are needed to complete a whole lap.


The green circle on the figure represents the turn that the earth's axis describes when it swings due to the precession movement.

In 2,100 years more or less the pole will be situated in Cepheus constellation, and 12,000 years will have to go by so that the honour of being the polar star corresponds to VEGA, in the  Harp constellation.

In 21,160 years’ time, Thuban will be the polar star, and in 25,780 years’ time the same story will happen again: our Polaris will dominate the celestial north.


When Egyptian s built up their pyramids, they pointed them to the only static star in the sky. Unlike us, probably they did not know why it did not move, but maybe they thought that it was a magic and motionless point. Therefore, they alienated their colossal funerary monuments towards it.


Today, the Egyptian polar star (THUBAN) no longer points to the N orth, and therefore the pyramids have become a bit old fashioned.

Another curious consequence of this phenomenon is that the Zodiac constellations, conceived of at that time, no longer are where they used to be.


Thus, our Zodiac sign is slightly moved backwards, and it nearly corresponds to the previous sign of those times. For example: everyone now born at the beginning of May will not be Taurus as he should have been 3,000 years ago, but Aries. Likewise, those who are Lion should think that they are actually Cancer. .....

¿Will this be the reason why horoscopes never guess our future.... ?


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