From a horizontal frame of reference, the path of the Sun looks like a part of a circle in a tilted plane, as shown in this picture:
If you go to a heliocentric system, one would say that this is because the Earth is rotating around it's axis. Is there any more detailed explanation of this change of reference?
So how can one explain in detail the following facts (seen from a geocentric point of view - horizontal reference system) starting from a heliocentric system and the fact that the Earth is rotating around it's axis:
- Why is the path of the Sun a part of a circle?
- Why is this path in a plane?
- Why is this plane tilted?
- How to get this "tilt-angle"?
Why does this motion seem to be uniform from an equatorial point of view, and can I neglect the ecliptic to understand the points above?
I tried to model it using a ball as Earth, attached a camera to it and used another ball as the Sun, but I didn't succeed in reproducing the effect of the apparent motion in this model. Perhaps there is any animation which makes the points above clear.