SternisheFan sends this excerpt from a JPL news release:
"NASA's Cassini spacecraft has obtained the highest-resolution movie yet of a unique six-sided jet stream, known as the hexagon, around Saturn's north pole. This is the first hexagon movie of its kind (GIF), using color filters, and the first to show a complete view of the top of Saturn down to about 70 degrees latitude. Spanning about 20,000 miles (30,000 kilometers) across, the hexagon is a wavy jet stream of 200-mile-per-hour winds (about 322 kilometers per hour) with a massive, rotating storm at the center. There is no weather feature exactly, consistently like this anywhere else in the solar system. 'The hexagon is just a current of air, and weather features out there that share similarities to this are notoriously turbulent and unstable,' said Andrew Ingersoll, a Cassini imaging team member at the California Institute of Technology in Pasadena. 'A hurricane on Earth typically lasts a week, but this has been here for decades — and who knows — maybe centuries.'"