Saturn's northern pole boasts a towering, hexagon-shaped vortex that rises high above the gas giant's clouds. Photo by NASA/JPL-Caltech/SSI/Hampton University
Sept. 4 (UPI) -- Newly analyzed data collected during the Cassini mission has revealed a hexagon-shaped vortex rising above Saturn's clouds. The vortex boasts the same shape as a similar vortex found deep within Saturn's atmosphere.
"While we did expect to see a vortex of some kind at Saturn's north pole as it grew warmer, its shape is really surprising," Leigh Fletcher of the University of Leicester said in a news release. "Either a hexagon has spawned spontaneously and identically at two different altitudes, one lower in the clouds and one high in the stratosphere, or the hexagon is in fact a towering structure spanning a vertical range of several hundred kilometers."
Scientists have previously observed a summertime vortex on Saturn's southern pole, but for the last few decades, it's been winter time on the gas giant's north pole.
"One Saturnian year spans roughly 30 Earth years, so the winters are long," said Sandrine Guerlet, researcher at France's Dynamic Meteorology Laboratory. "Saturn only began to emerge from the depths of northern winter in 2009, and gradually warmed up as the northern hemisphere approached summertime."
The new research, detailed in the journal Nature Communications, suggests the northern vortex helped accelerate the warming of the northern pole, allowing scientists to image Saturn's study the polar vortex in infrared light.
Cold temperatures disrupt infrared images. Until 2014, scientists couldn't use Cassini's Composite Infrared Spectrometer to analyze the upper layers of Saturn's northern atmosphere.
"As the polar vortex became more and more visible, we noticed it had hexagonal edges, and realized that we were seeing the pre-existing hexagon at much higher altitudes than previously thought," Guerlet said.
Astronomers are skeptical that low-lying winds could penetrate upward to create the towering hexagon. And yet, the latest research suggests a link between the lower and higher vortexes is possible. As usual, more research is needed.
Unfortunately, Cassini is no longer around to offer detailed observations of the gas giant. The probe ended its mission last fall.
