Never Seen Before: Scientists Baffled by Perfectly Geometric Polygonal Storms on Jupiter

At Jupiter’s north pole there is an impressive display of geometric precision, with a large perfectly-shaped cyclone surrounded by eight smaller ones. In the same way, five smaller cyclones dance around the large one at its south pole.

There is a perfect geometrical pattern of cyclones around the poles of Jupiter and Saturn. Over the course of years, Jupiter’s poles have been ravaged by massive cyclones that swirled in perfect geometric formation, scientists have now shown. There are eight smaller cyclones surrounding a large one at the north pole of the planet. In a similar manner, five smaller cyclones dance around the central large one at the south pole.

On the other hand, Saturn possesses only one vortex, or cyclone, at each pole. Observations of the geodetic storms at the poles by the Juno spacecraft in 2017 have baffled scientists who have been trying to find a reason as to how and why these storms exist at all. Despite their swirling nature, these winds are remarkably stable. According to a previous study, they remain tightly arranged in octagons without drifting apart or merging. Researchers at the California Institute of Technology, led by Andrew Ingersoll, have published a new study in Nature Astronomy that may explain why these cyclones are so stable. For the polygonal pattern to remain stable, an “anticyclonic ring” of winds blowing oppositely around the big cyclone at its center and the smaller ones surrounding it is needed.

 

To understand how this formation remains stable, scientists previously attempted to replicate polygonal storms. Researchers in the paper stated that in previous theoretical studies, stable cyclones were shielded (by an anticyclonic vorticity ring around each cyclone), and stable ones were not. Scientists were able to observe the pole at scales as small as 180 kilometers using JIRAM, Junos Infrared Auroral Mapper. Every eight minutes, the instrument captured 12 images of Jupiter’s north pole as it flew past the gas giant.

 

Observations by JIRAM of Jupiter’s poles revealed that the cyclones were stabilized by strong winds blowing in the opposite direction. Despite the images clarifying some things, there are still many questions left to be answered. It was expected, for example, that convection would occur within the cyclones (a heat transfer method within fluids). As it turned out, this was not the case.   The scientists recommended that further study in the field be conducted due to the uncertain implications for convection. According to the study, “a parallel investigation of Jupiter’s south pole vortices focusing on vorticity and stability represents a step in the right direction.”