Images: Mysterious hexagon spotted on Saturn

A strange hexagon shape over the north pole of Saturn was first spotted by the two Voyager spacecraft and has been revisited by the Cassini probe. The long duration between sightings indicate it is likely a permanent feature according to NASA scientists. In fact, Cassini found a second hexagon, significantly darker than the orginal. This is the first time the feature has been captured on one image.

On NASA's Web site, Kevin Baines, atmospheric expert and member of Cassini's visual and infrared mapping spectrometer team at NASA's Jet Propulsion Laboratory, said, "Saturn's thick atmosphere where circularly-shaped waves and convective cells dominate is perhaps the last place you'd expect to see such a six-sided geometric figure, yet there it is."

This image was captured at night. The red color indicates heat generated from the planet's interior.