The atmosphere of Jupiter shows light and dark bands of clouds in a range of colors. The light bands, called zones, are high in the atmosphere and indicate upwelling gas; the dark bands, or belts, are lower and show where gas is descending. The zones and belts are driven by eastward and westward winds of up to 540 kilometers per hour. Adjacent cloud bands are often moving in opposite directions, driving turbulent eddies around the planet. Of these eddies, which appear as light or dark ovals, the most prominent is the Great Red Spot (16,280 x 8,575 miles). Located in the southern hemisphere, this storm is more than twice the size of Earth and rotates in a counterclockwise direction every four to six days. The Great Red Spot was observed over 300 years ago, but researchers believe it could be millions of years old.
