NASA/JPL-Caltech/SSI/Hampton
NASA's Cassini spacecraft has captured the highest-resolution view of Saturn's "hexagon" - a wavy jet stream at the planet's north polar region, spanning roughly 20,000 miles across.
"The hexagon is just a current of air, and weather features out there that share similarities to this are notoriously turbulent and unstable," Andrew Ingersoll, a Cassini imaging team member at the California Institute of Technology in Pasadena, said in a statement.
The hexagon is packing 200-mile-per-hour winds and has a giant rotating storm at the center, according to NASA. There are also many vortices - with the largest vortice measuring more than 2,000 miles across - that spin in the opposite direction of the hexagon.
"There is no weather feature exactly, consistently like this anywhere else in the solar system," writes NASA.
Scientists believe the hexagon has remained stable for hundreds of years because Saturn lacks solid landforms that would typically interrupt weather patterns on Earth.
"A hurricane on Earth typically lasts a week, but this has been here for decades - and who knows - maybe centuries," Ingersoll said.
The hexagon was first discovered by the Voyager mission in the early-1980s. When Cassini arrived at Saturn in 2004, the north pole was dark and it was impossible to get good views of six-sided shape. As Saturn's seasons changed, moving into northern spring, the sun began to light up the interior of the hexagon. Cassini began imaging Saturn's poles at the end of 2012.
The animation above was made from a combination of more than 100 images taken over a period of 10 hours on Dec. 10, 2012.
In the movie, scientists assigned colors to different wavelengths of light to show the contrast between large and small haze particles. There is a large concentration of small haze particles inside the hexagon, represented by the color blue. (In natural color the hexagon would appear in shades of blue and gold).
Scientists expect to get even better views of Saturn's north pole as the planet approaches its summer solstice in 2017 and lighting conditions improve.