The Hexagonal Storm on Saturn

Saturn's Hexago

Image Credit:

NASA/Cassini

North Polar Hexagon on Saturn

Image Credit:

NASA/JPL-Caltech/Space Science Institute

 

One of the strangest features on Saturn is the hexagon-shaped storm in its northern hemisphere. The storm was first discovered by Voyager in 1981-1982 and has been persistent since. It is located at 78° N latitude, but does not change longitude over time, unlike other storms on Saturn. The sides of the storm are about 13,800 km, longer than the Earth's diameter of abotu 13,500 km.

The Cassini mission also has taken images of the storm since its arrival in 2006. And if the conditions are right, i.e. the storm is in daylight, fuzzy images of the storm can be seen from Earth-based telescopes, even by amateur astronomers.

Oxford University astronomers proposed a hypothesis for the formation of the storm. In the lab, regular shpaes were created in a circular tank of liquid that had different rotation rates at the center and at the edges. Squares, hexagons, and octagons were all created, with hexagons being the most common shape. These latitudinal gradients in the rotation are one probable cause for the hexagon on Saturn.