The rotation axis of the Earth is inclined relative to the plane of its orbit around the Sun. Because of the inclination of the rotation axis, Earth's hemispheres are never exposed equally within a year to the illumination (and heating) of the Sun. That's why we have seasons. Seasons are in opposition between North and South, thus when we have winter in the northern hemisphere we have summer in southern and the other way around.
However. The rotation axis which is constant around 23 degrees wobbles relative to solar system axis within a 23 thousand years cycle (pure coincidence of numbers).
This rotation of the axis within a 23 thousand years period is called precession. But it is so slow it would not make any noticeable difference to others than astronomers within let's say 1000 years.
The ancient ones knew about it. The djed in Egyptian pictogram (representing Earth's magnetic field and its true cause, the electrojets and generally rotation of the charged atmosphere) is tilted at 23 degrees).
And here's where the trouble begins. When let's say Earth is farthest from Sun in the same time with Earth being inclined with Northern hemisphere away from Sun we have an ice age in the North. However the ice age propagates within the whole planet which is being cooled because of ice's reflectivity with a northerly ice age starting earlier and ending later in North. Close to this theory we have
https://www.google.com/search?q=milankovitch+cycles&gws_rd=ssl
According to this theory the most livable time on the whole planet is right in between of maximum of glaciations or equal glaciations between North and South, or the present moment. And place, around Equator, probably most time. Soon, that is in a few thousand years or so, we're going to start freezing in the southern hemisphere.
This is known to astronomers and to many others as the "astronomical theory of ice ages", although by the general public is confused with pseudoscience. Also.
http://en.wikipedia.org/wiki/Precession#Astronomy
But here comes the real interesting part. I've been looking through the peep hole that is the northern shaft of the Great Pyramid. (With Stellarium, of course. That is i put in Stellarium - a free planetarium app for Windows and Linux - on the exact coordinates of the Great Pyramid and directed the view towards the direction of the shaft). What i've seen right away is... Polaris. I moved the time to the year 2105 when by astronomical predictions Polaris is supposed to point Earth's geographic North within about 14 minutes of an arc (not specified where on Earth from) . From the latitude of the pyramids, it's within just less than a degree. http://stars.astro.illinois.edu/sow/polaris.html
According to Stellarium, in the year -23650 there was also an alignment of the shaft within less then of a degree.
A few hundred years before 2105, it was within 1.5 degrees or so, so it will be a few hundreds after. Then it starts getting even further. That means Polaris will be the best indication for Earth's geographic North Pole around year 2105.
Through the shaft in that year, we can see it within less than a degree or so, a bit less than today (throughout daily or yearly cycle). That means we are 90 years away from the middle of the cycle.
So will be @ 27820. But Stellarium is not a true astronomical prediction tool. It only works with currently known orbits not affected by gravity. So it gives a predicted precession period of about 25700 years instead of other calculations of about 25920.
However Milankovitch cycles predict a complete glaciation cycle of about 23000 years (second paragraph).
At any other time, Earth geographic North Pole is away from Polaris, the furthest right in between, when Polaris is at double the inclination angle, 2x23 decrees, that is about 46 degree.
According to all these, 13000 years from now, "down under" will finally be winter at Christmas time... But in the mean time we will have an ice age at South Pole that would probably include Australia and a complete meltdown of the polar cap in North.
The ancient ones knew about it. The djed in Egyptian pictogram (representing Earth's magnetic field and its true cause, the electrojets and generally rotation of the charged atmosphere) is tilted at 23 degrees).
In the same time, the orbit itself is not a perfect circle, but an ellipse. The images below are exaggerated showing the orbit of Earth around Sun is not a circle but an ellipse with about 5% difference between the two diameters with Sun in one of the two centers.
And here's where the trouble begins. When let's say Earth is farthest from Sun in the same time with Earth being inclined with Northern hemisphere away from Sun we have an ice age in the North. However the ice age propagates within the whole planet which is being cooled because of ice's reflectivity with a northerly ice age starting earlier and ending later in North. Close to this theory we have
https://www.google.com/search?q=milankovitch+cycles&gws_rd=ssl
According to this theory the most livable time on the whole planet is right in between of maximum of glaciations or equal glaciations between North and South, or the present moment. And place, around Equator, probably most time. Soon, that is in a few thousand years or so, we're going to start freezing in the southern hemisphere.
This is known to astronomers and to many others as the "astronomical theory of ice ages", although by the general public is confused with pseudoscience. Also.
http://en.wikipedia.org/wiki/Precession#Astronomy
But here comes the real interesting part. I've been looking through the peep hole that is the northern shaft of the Great Pyramid. (With Stellarium, of course. That is i put in Stellarium - a free planetarium app for Windows and Linux - on the exact coordinates of the Great Pyramid and directed the view towards the direction of the shaft). What i've seen right away is... Polaris. I moved the time to the year 2105 when by astronomical predictions Polaris is supposed to point Earth's geographic North within about 14 minutes of an arc (not specified where on Earth from) . From the latitude of the pyramids, it's within just less than a degree. http://stars.astro.illinois.edu/sow/polaris.html
According to Stellarium, in the year -23650 there was also an alignment of the shaft within less then of a degree.
A few hundred years before 2105, it was within 1.5 degrees or so, so it will be a few hundreds after. Then it starts getting even further. That means Polaris will be the best indication for Earth's geographic North Pole around year 2105.
Through the shaft in that year, we can see it within less than a degree or so, a bit less than today (throughout daily or yearly cycle). That means we are 90 years away from the middle of the cycle.
So will be @ 27820. But Stellarium is not a true astronomical prediction tool. It only works with currently known orbits not affected by gravity. So it gives a predicted precession period of about 25700 years instead of other calculations of about 25920.
However Milankovitch cycles predict a complete glaciation cycle of about 23000 years (second paragraph).
At any other time, Earth geographic North Pole is away from Polaris, the furthest right in between, when Polaris is at double the inclination angle, 2x23 decrees, that is about 46 degree.
According to all these, 13000 years from now, "down under" will finally be winter at Christmas time... But in the mean time we will have an ice age at South Pole that would probably include Australia and a complete meltdown of the polar cap in North.

