The planet Neptune has an average rotational speed of just over 16 hours. Like the other gas giants, Neptune lacks a solid surface, and the speed at which different parts of the planet rotate can vary due to a process known as differential rotation.
The equatorial regions of Neptune have a rotation speed that is slower than the planetary average. These regions take approximately 18 hours to complete a single rotation, while the polar region of the planet turns once every 12 hours. The difference in rotational speeds creates a strong latitudinal wind sheer effect, producing winds that can reach speeds of up to 1,500 mph.