Saturn's hexagon

[19] After its discovery, and after it came back into the sunlight, amateur astronomers managed to get images showing the hexagon from Earth, even with modest-sized telescopes.

[22][23] A number of stable vortices of similar size form on the slower (south) side of the fluid boundary and these interact with each other to space themselves out evenly around the perimeter.

Other researchers claim that lab studies exhibit vortex streets, a series of spiraling vortices not observed in Saturn's hexagon.

[24] Developing barotropic instability of Saturn's North Polar hexagonal circumpolar jet (Jet) plus North Polar vortex (NPV) system produces a long-living structure akin to the observed hexagon, which is not the case of the Jet-only system, which was studied in this context in a number of papers in literature.

The influence of moist convection, which was recently suggested to be at the origin of Saturn's NPV system in the literature, is investigated in the framework of the barotropic rotating shallow water model and does not alter the conclusions.

Although apparently shielded, the polar cyclone on Saturn cannot hold a polygonal pattern of circumpolar cyclones such as Jupiter's due to the bigger size and slower wind speed of Saturn's polar cyclone, so the side-adjacent vortices and deep barotropic instability (Cassini's wind speed measurements preclude shallower barotropic instability at least at the time of the Cassini encounter), or possibly baroclinic instabilities remain as the most viable explanations for Saturn's sustained hexagon.