I. The Facts
II. Round Earth Explanation
III. Flat Earth Explanation
I. The Facts1. Facing North, stars circle around a single point in the sky. This is called the
North Celestial Pole.
2. Facing South, stars circle a different point in the sky. This is called the
South Celestial Pole.
3. In the Northern Hemisphere, the North Celestial Pole is above the horizon, and the South Celestial Pole is an equal distance below* the horizon.
4. In the Southern Hemisphere, the South Celestial Pole is above the horizon, and the North Celestial Pole is an equal distance below* the horizon.
5. The North Celestial Pole is due north. The South Celestial Pole is due south. They are in
exactly opposite directions from one another.
![](http://imgur.com/pbzmZfN.png)
Here are both celestial poles in one image. North Celestial Pole is on the left above the horizon. South Celestial Pole is on the right, below the horizon. Forgive the distortion, it's a panoramic image:
![](http://apod.nasa.gov/apod/image/1403/archtrails_brady_960.jpg)
* Obviously we can't actually see the celestial pole that is below the horizon. However, we can approximate it's position by extrapolating the paths of the stars.
II. Round Earth ExplanationThe earth is a rotating sphere. From our perspective, the stars appear to be rotating around us. The elevation of each celestial pole depends on your location on the earth.
At 30 degrees north of the equator, the North Celestial Pole will be 30 degrees above the horizon and the South Celestial Pole will be 30 degrees below the horizon. Likewise, at 30 degrees south of the equator, the South Celestial Pole will be 30 degrees above the horizon and the North Celestial Pole will be 30 degrees below the horizon.
![](http://imgur.com/plalvVn.png)
You can confirm for yourself that the elevation of each celestial pole corresponds exactly with your own latitude.
III. Flat Earth ExplanationObviously, the visibility of the South Celestial Pole presents a problem for the flat earth model. If the stars are all rotating around a vertical axis, then the South Celestial Pole should be below the earth. In order to see it, one would have to peek over the edge. "Celestial Gears" are the most common solution to this problem that I have seen. I have never seen a particularly detailed explanation of how they work, but I assume it is something like this:
![](http://imgur.com/v7FtuqJ.png)
However, this still presents some problems.
1. There has never been a report of anyone seeing an intersection between the various South Celestial Poles. Considering that mankind has been navigating the oceans by the stars for several hundred years, this seems unlikely.
2. The South Celestial Pole is always
exactly due South. It is always 180 degrees in the opposite direction of North. In the "Celestial Gears" model, moving east or west would cause the South Celestial Pole to no longer be due South. There would be a non 180 degree angle between the North Celestial Pole and South Celestial Pole.
![](http://imgur.com/aPgncKh.png)
The
Bipolar Model has the exact same problem.
In conclusion, the visibility of the South Celestial Pole is in direct contradiction with the flat earth model. The earth isn't flat.