Mercury retrograde animation in the heliocentric theory
It shows Mercury moving across the horoscope. When the red dot moves in the opposite direction, Mercury is said to be retrograde. In this animation, the yellow disc is the Sun. Mercury orbits the Sun, and the red dot shows its position seen from Earth.
Ptolemy’s question and the geocentric theory
The Moon and the Sun do not move retrograde. Why do the five other planets go direct and retrograde?
The conclusion Ptolemy reached was that the five planets move very complexly.
It is an animation of planets’ motion from the geocentric theory’s perspective. It shows the motion of the Moon, Mercury, Venus, and the Sun, with the Earth at the center.
Mercury’s motion as seen from Earth
A simulation of Mercury’s motion around the Sun at noon every day from October 2024 to December 2025 shows how we see from Earth. [by Stellarium]