November 18, 2013 - Casting a Hex on Saturn

Casting a Hex on Saturn This Cassini image of the north polar region of Saturn shows both an aurora and the underlying atmosphere, seen at two different wavelengths of infrared light. Visible directly below the aurora is the hexagonal cloud structure first noted by the Voyager spacecraft and still visible by Cassini. The hexagon is about 25,000 km (15,000 mi) across, large enough that four Earths could fit inside it. The strong brightness of the hexagon feature indicates that it is primarily a clearing in the clouds, which extends deep into the atmosphere, about 75 km (47 mi) below the clouds and haze seen in visible wavelengths. In 2010, researchers created a similar structure in a laboratory experiment and concluded that the hexagonal shape is related to a jet stream in Saturn’s atmosphere.

Image credit: NASA / JPL / University of Arizona