Geocentric & Heliocentric Models

Kira Reynolds


In this project, I am going to explain the Geocentric and Heliocentric solar system models. I will also compare and contrast them.

Geocentric Solar System Model

The Geocentric model was the first solar system model that was introduced. It is also called the Ptolemaic system. The model places the sun, and other planets revolving around Earth. The model also portrays that the Earth is not moving and that everything is moving around us. It was created by Greek philosophers, primarily by Claudius Ptolemy.

Heliocentric Solar System Model

The Heliocentric model replaced the Geocentric model when new evidence was discovered that the Earth was not the center of the universe. The model places Earth, and other planets revolving around the sun. Earth revolves around the sun and rotates on its own axis. Astronomer Nicolaus Copernicus, made a book on the theory called On the Revolutions of Heavenly Spheres.

Comparing Geocentric & Heliocentric

The major similarity is that the sun, moon, and planets are present. Also, the moon revolves around the earth in both models. They both have a universal center.

Contrasting Geocentric and Heliocentric

The major difference is their opposing theories. Geocentric places the Earth at the center, and Heliocentric places the Sun at the center of the universe. The planets and the sun are differently arranged in both of them.


In this project, I explained the two solar system models, and gave some similarities and differences between them.