NASA | JPL-Caltech | Cassini | 2018 Sep 05
The finding, published Sept. 3 in Nature Communications, is intriguing, because it suggests that the lower-altitude hexagon may influence what happens above, and that it could be a towering structure hundreds of miles in height.
When Cassini arrived at the Saturnian system in 2004, the southern hemisphere was enjoying summertime, while the northern was in the midst of winter. The spacecraft spied a broad, warm high-altitude vortex at Saturn's southern pole but none at the planet's northern pole. The new study reports the first glimpses of a northern polar vortex forming high in the atmosphere, as Saturn's northern hemisphere approached summertime. This warm vortex sits hundreds of miles above the clouds, in the stratosphere, and reveals an unexpected surprise.
"The edges of this newly-found vortex appear to be hexagonal, precisely matching a famous and bizarre hexagonal cloud pattern we see deeper down in Saturn's atmosphere," said Leigh Fletcher of the University of Leicester, lead author of the new study. ...
Saturn's Famous Hexagon May Tower Above the Clouds
ESA Science & Technology | University of Leicester | 2018 Sep 04
A Hexagon in Saturn's Northern Stratosphere Surrounding the Emerging Summertime Polar Vortex ~ L.N. Fletcher et al