Part 6/11:
Polaris is not a fixed point in space; it is a star that happens to lie nearly along Earth's current rotational axis, making it appear stationary in the sky. However, over thousands of years, Polaris's position shifts gradually due to the precession of Earth's axis. Currently, it is the North Star, but this role will eventually be taken over by other stars as Earth's axial orientation slowly changes.
Other stars visible to the naked eye, like those in Cassiopeia, are situated thousands of light-years away but are moving within the galactic frame. Because of their immense distances, their apparent positions change extremely slowly—over millennia—making their positions in the sky appear stable in our human lifetime.