Jupiter can have its Great Red Spot, Neptune has its Great Dark Spot. About the size of Earth, this spot appears to be rising currents of gas. Smaller spots, named Scooter and D2 are found in the southern latitudes. Wispy clouds of frozen methane ice crystals in the upper atmosphere are also visible. Since the atmosphere changes over time, something has to be driving it.
Astronomers believe that the atmosphere is being driven by heat flowing from the interior.
This rising heat causes convection in the atmosphere which, along with the rapid rotation of Neptune, causes high speed winds to develope. . The only logical explanation for this internal heat is leftover heat from Neptune's formation. The current model for Neptune is a a rocky core surrounded by a slushy mix of molecular hydrogen, ammonia and methane with thick layers of water clouds. Rings have turned out to be a common thing in the outer solar system, and Neptune is no exception, though they are strange rings indeed. The reason for this strange appearance is directly connected with the moons of Neptune.