Saturn's mysterious hexagon shows its true colors

A true-color view from the camera on NASA's Cassini orbiter, captured on Oct. 10, shows Saturn's north polar region and its rings. The planet's mysterious hexagon-shaped polar storm can be seen in bluish shades. This picture was taken from a distance of about 935,000 miles (1.5 kilometers). NASA / JPL / SSI / Composite by Val Klavans

Astronomers have oohed and ahhed over Saturn's hexagonal storm system for decades, but it hasn't looked any cooler than it does in this picture from NASA's Cassini spacecraft, which has been orbiting the ringed planet for more than nine years.

The hexagon is nearly 15,000 miles (25,000 kilometers) across — big enough for nearly four Earths to fit inside. Cassini's pictures usually show the storm in infrared wavelengths, with a deep red glow or perhaps in false-color shades of red, orange and green. This picture, in contrast, was processed to approximate the hexagon's true colors.

"This composite image will be part of a large Saturn mosaic I am currently working on for 'In Saturn's Rings,'" Val Klavans, image processor and social media team leader for the big-screen film project, said in an email. Nine frames from Cassini's camera will be pieced together to produce the finished picture.

"The mosaic will feature most of Saturn's globe, a shadow cast on the rings from the planet, and entire hexagon. This other composite image will also be part of the mosaic," Klavans wrote.

Check out the Titan Saturn's Moon website for more from Klavans, and keep an eye out for "In Saturn's Rings" in movie theaters next year. For more about Cassini, check in with NASA's mission website and the CICLOPS imaging team's website as well. (Spoiler alert: The imaging team is working on its own big Saturn mosaic.)

More stunners from Saturn:

Are you wondering how a storm turns into a hexagon? The Planetary Society's Emily Lakdawalla explains it all for you.

Alan Boyle is's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with's stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.