Anneke van Hall

The Geocentric and Ptolemaic Models

The geocentric model of the earth was one of the first theories formulated regarding the position of the sun, moon and planets in our solar system. This theory put the earth in the center of the solar system with the sun and the objects revolving around it. Before this theory was refuted, it was used by many Greek philosophers and astronomers such as Aristotle. As people were not scientifically advanced in the ancient Greek times, they believed that the earth was stationary and that the movement they saw was from objects orbiting around it. Many also believe this theory was formed due to the way it appears the sun, moon, and planets revolve around the earth when observing the sky in the northern hemisphere.

Geocentric Model:

After the geocentric model was formed, it encouraged more research on the solar system. Cladius Ptolemy created the Ptolemaic model of the solar system which was based off the geocentric model, but predicted the known planets whereabouts more accurately. Cladius Ptolemy still had a lot to learn about the solar system, but his theory helped advance the study of astronomy in other astronomers.

Ptolemaic model:

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