NASA’s Cassini spacecraft has obtained the highest-resolution movie yet of a unique six-sided jet stream, dubbed as the hexagon, around Saturn’s North Pole.
Spanning about 20,000 miles (30,000 kilometers) across, the hexagon is a wavy jet stream of 200-mile-per-hour winds (about 300 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.
Andrew Ingersoll, a Cassini imaging team member at the California Institute of Technology in Pasadena, said that the hexagon is just a current of air, and weather features out there that share similarities to this are notoriously turbulent and unstable.
Better views of the hexagon are available now because the Sun began to illuminate its interior in late 2012. Cassini captured images of the hexagon over a 10-hour time span with high-resolution cameras, giving scientists a good look at the motion of cloud structures within.
They saw the storm around the pole, as well as small vortices rotating in the opposite direction of the hexagon. Some of the vortices are swept along with the jet stream as if on a racetrack.
The largest of these vortices spans about 2,200 miles (3,500 kilometers), or about twice the size of the largest hurricane recorded on Earth.
Scientists analyzed these images in false color, a rendering method that makes it easier to distinguish differences among the types of particles suspended in the atmosphere -- relatively small particles that make up haze -- inside and outside the hexagon.