Describe the Ptolemaic model for planetary motion.

(N/A) The Ptolemaic model,proposed by Claudius Ptolemy in the $2^{nd}$ century $AD$,is a geocentric model of the universe.
$1$. It posits that the Earth is stationary at the center of the universe.
$2$. All celestial bodies,including the Sun,Moon,planets,and stars,revolve around the Earth in complex circular paths.
$3$. To explain the observed retrograde motion of planets (where they appear to move backward in the sky),Ptolemy introduced the concept of 'epicycles'.
$4$. In this system,each planet moves in a small circle called an 'epicycle',while the center of this epicycle moves along a larger circular path around the Earth called a 'deferent'.
$5$. This model was the dominant cosmological framework for over $1,400$ years until it was replaced by the heliocentric model proposed by Nicolaus Copernicus.