Celestial spheres

Imagine if the stars, planets, and other things in space were all stuck to a giant invisible ball that surrounded the Earth like a big bubble. This is what people used to believe a long, long time ago, and they called it the celestial sphere.

They thought that the Earth was at the center of the universe and that everything in the sky rotated around it on these spheres. They believed that there were different layers, or spheres, for different things in the sky – like one for the stars, one for the Moon, and one for the Sun.

The idea of celestial spheres was used to explain how everything in the sky moved. They thought that each sphere was fixed in place and that the stars, Moon, and planets moved around it like a clock. They thought that the sphere for the stars was the furthest away from Earth and the one for the Moon was the closest.

Even though we now know that the universe isn't structured like this and that the Earth isn't the center of it, the idea of celestial spheres helped people to understand the movements of the skies and the passing of time.