Animation of the movements of the cloud bands of Jupiter. The bands move in different directions at different latitudes, as they do on Earth, due to the effects of convection and the planet磗 rotation. At the boundaries between the bands, the interaction of opposite flows causes turbulence and huge storm systems. The Great Red Spot, visible in the southern hemisphere, has been observed for hundreds of years. The upper clouds of Jupiter are formed of ammonia and ammonium hydrosulfide, with ammonia ice responsible for the light colour of the zones. The dark colour of the so_called belts is not as well understood.