Some geometric models of ancient astronomy with Geogebra

The main objective of this work is to review and simulate, with the help of GeoGebra, the most important geometric models used by the ancient astronomers to explain the mechanisms governing the trajectories of celestial bodies in the sky. It is well known that ancient astronomers like Ptolemy, Copernicus, Galileo, invented the same complex geometric systems of circles to explain the motion of the celestial bodies. It was not until Kepler, with the introduction of conics in the geometric models, that it was possible to accurately explain the observations with theoretical models.