## The geocentric model

The geocentric model, also known as the Ptolemaic system, is a theory that was developed by Claudius Ptolemy in Ancient Greece. It was developed to explain how the planets, the Sun, and even the stars orbit around the Earth. The geocentric theory has existed even before Ptolemy though. This model has been described in various early Greek manuscripts, and as early as the 4th century B.C. Plato and Aristotle were writing about the geocentric model.

Ptolemy’s version of the geocentric model was a combination of complex circles. According to this theory, all the planets and even the sun, orbited around the Earth. Ptolemy believed that all the space bodies orbited around a circle, which was termed an epicycle, and those circles orbited on a bigger circle, the deferent, around the Earth. A diagram of this geocentric model would look like as mess of overlapping circles.

Despite its complications, the geocentric model was the prevailing theory in Ancient Greece, throughout Europe, and other parts of the world for centuries.. It was because it fit into the number of observations made by the Greeks over the years and because the Church accepted it.

Despite its complications, the geocentric model was the prevailing theory in Ancient Greece, throughout Europe, and other parts of the world for centuries.. It was because it fit into the number of observations made by the Greeks over the years and because the Church accepted it.

## Important words

Epicycle: A small circle whose center moves around the circumference of a larger circle.

Deferent: The larger circular orbit epicycles move on.

Deferent: The larger circular orbit epicycles move on.