Editing Apparent retrograde motion (section)

=== From Mercury ===

From any point on the daytime surface of [[Mercury (planet)|Mercury]] when the planet is near [[perihelion]] (closest approach to the [[Sun]]), the Sun undergoes apparent retrograde motion. This occurs because, from approximately four Earth days before [[perihelion]] until approximately four Earth days after it, Mercury's angular [[orbital speed]] exceeds its angular [[rotational velocity]].<ref>Strom, Robert G.; Sprague, Ann L. (2003). ''Exploring Mercury: the iron planet''. Springer. {{ISBN|1-85233-731-1}}.</ref> Mercury's elliptical orbit is farther from circular than that of any other planet in the Solar System, resulting in a substantially higher orbital speed near perihelion. As a result, at specific points on Mercury's surface an observer would be able to see the Sun rise part way, then reverse and set before rising again, all within the same [[Extraterrestrial skies#Mercury|Mercurian day]].