In a figure, Mercury is shown as a circle. Plus, the center and an arc that through the center and is extending upward and downward (that is a part of orbit) are shown. This arc divides Mercury into left and right, and the area is left > right. This figure will show that actual magnitude of centrifugal force exceeds that calculated for Mercury as a point (see formula of centrifugal force). Perihelion shift of Mercury may be due to Mercury's size.
