What was the old model for understanding the universe illustrated by concentric circles?

The old model for understanding the universe, often illustrated by concentric circles, is the geocentric model, which posits that the Earth is at the center of the universe. In this view, celestial bodies, including the Sun, Moon, and planets, revolve around the Earth in circular orbits. This model was predominant in ancient and medieval astronomy, primarily influenced by philosophers like Aristotle and Ptolemy. It was eventually challenged and replaced by the heliocentric model, which places the Sun at the center of the solar system.