What the cloud layers above Saturn’s hexagon are made of

Jupiter has its Great Red Spot – Saturn, in contrast, has its enormous hexagon. For a long time, a six-sided structure with a diameter of 29,000 km (18,000 miles) has been rotating around Saturn’s north pole. Thus, the hexagon is considerably larger than Jupiter’s spot, which is only 16,000 km (10,000 miles) across and more than twice as large as the whole Earth. The hexagon was first discovered in 1981 by Voyager 1 (photographed in infrared in the image below).

Starting in 2006, the Cassini pro...