a simple celestial timepiece

The North Star is like the center of the face of a clock. The center does not move. Two bright constellations (along with the rest of the stars from our earthling perspective) revolve around the North Star: The Big Dipper and Cassiopeia's Chair. They are always opposite each other, with the north star between them.

If you were in a dark place (in the Northern Hemisphere) and spent a clear night watching The Big Dipper and Cassiopeia's Chair, you would see the two constellations slowly chasing each other around the North Star in a great circle. It's fascinating, a simple celestial timepiece! The position of either one of the constellations and the North Star can tell you what season and time it is.