Glad you are back Bodkins and Sorry to hear you saw no green lights.

The north star.. is it not only visible from the northern hemisphere? It's the north star .. it's North.
At some point on the southern hemisphere you are not going to see the north start, how did they navigate the seas without a visible north star?
For reference see link given us by Bodkins for ASD Planetarium: The Reasons for the Seasons.

Electromagnetic Anisotropy, Perspective or the location of the viewer, yes.
Motion and movement, for example,
a pendulum moves back and forth in a straight line or in a simple spiral or a vortex depending upon your reference point, the location of the viewer in space.

And below I go off on a wild tangent wondering ...
A straight line movement from one view point would appear as a a spiral or a vortex from another view point .. think about it.

A vortex from our view point is just a straight line movement from a another view point. .. So a vortex is straight line movement from point A to point B from a different perspective and why a vortex is so hard to visualize.
The shortest path is from point A to point B, the line of least resistance is usually a vortex. Is a vortex a straight line movement from point A to point B from a different location of view? Oh, I'm hurting my brain.

We could pretend that gravity and the magnetic field of the earth work together to create a vortex movement as the earth rotates on it's axis, but is it that easy to explain. Does that explain the movement observed?

Could an observed vortex movement be caused by a single force?
Yes it could if that force was being applied to our location as the viewer, was from another location outside of our view point.. A point in space.

A force, you could call it a friction or drag, between our location in space and some other location in space causes a vortex in our location or view point.
Some thing causes the vortex to happen in our location as the viewer.
Can gravity, magnetic fields etc from earth organize and maintain a vortex movement.

Perspective, we see a vortex. Is that vortex movement caused by a single force (name a force of your choice) between the standing still (space or whatever names) and the movement of the earth through space around the sun and rotation upon it's axis creates what we see as a vortex in our location in space as the viewer? Well DAH?!
The location of this force(s) (it's more like friction between here that where ever there is) that causes a vortex is where? Every where is the easy answer .. but is it the correct one?

I didn't get anything out of that except maybe a vortex motion could be caused by an unknown force.

ah, just
Randy