HD189733b is a gas-giant exoplanet with the highest wind speeds ever recorded for any planet. The planet is very close in to its parent star, so one face has a lot of heating. This difference in temperature between the night and day sides drives ferocious winds across the planet at speeds up to 2km per second. In this depiction, the planet is shown with a thick cloud band encircling its equator. On the side facing the star, the cloud is white. On the night side, the cloud is dark, seen in silhouette and backlit by the heat of the planet beneath it.