Prime purpose of this lecture is to present on Geocentric Model of Planetary Motion. Here briefly explains qualitatively the prograde and retrograde motions, and brightness variation. Motion planets around epicycle centers and epicycle centers around the Earth are uniform circular motions. Ptolemy (90-168 CE) modified this model to be quantitatively accurate compared to the observations of the time. His model was used for 1400 years until the Renaissance.
Geocentric Model of Planetary Motion
