The animation on the left shows the Sun, Earth, and Mars seen from a Sun-centered point of view, whereas the animation on the right shows the three bodies seen from an Earth-centered point of view. In the latter case, Mars seems to execute a complicated trajectory, at times moving counterclockwise (east), then stopping and moving clockwise (west), and stopping again, to regain its counterclockwise motion. Notice that at all times the relative positions of the three bodies are exactly the same in both reference frames.