Editing Rotation (section)

=== Retrograde rotation ===
{{Main|Retrograde motion}}

Most [[planet]]s in the [[Solar System]], including [[Earth]], spin in the same direction as they orbit the [[Sun]]. The exceptions are [[Venus]] and [[Uranus]]. Venus may be thought of as rotating slowly backward (or being "upside down"). Uranus rotates nearly on its side relative to its orbit. Current speculation is that Uranus started off with a typical prograde orientation and was knocked on its side by a large impact early in its history. The [[dwarf planet]] [[Pluto]] (formerly considered a planet) is anomalous in several ways, including that it also rotates on its side.