Saturn is the second largest planet in the solar system after Jupiter. The gas giant is particularly recognizable by its impressive ring system, composed mainly of dust particles and ice.
It turns out that the planet is the also the scene of another strange phenomenon recently revealed by the data collected by NASA’s Cassini-Huygens international mission.
A hexagon shaped swirl at very high altitude
As the summer begins in the northern hemisphere of Saturn, the Cassini-Huygens spacecraft has spotted a strange whirlpool that has formed over the North Pole of the planet. The vortex in question has a hexagonal shape and circulates in the stratosphere layer of the Saturn atmosphere, hundreds of kilometers above the clouds. The strange whirlwind is reminiscent of another polar vortex that had previously been discovered at the North Pole, but lower in the atmosphere. Scientists are now wondering about the origin of these hexagon-shaped objects, and whether they are related.
When NASA’s Cassini-Huygens spacecraft entered the Saturn system in 2004, it was summer in the southern hemisphere of the planet, and the probe had discovered a hot, circular whirlwind at the time at high altitude at the South Pole. Nothing was detected on the other hand in the northern hemisphere, where it was winter at the time. It is as if the hexagon-shaped vortices, at low and high altitude, are formed only at the north pole, while at the south pole circular vortices are formed.
The two poles of Saturn behave differently
The difference between the vortices that form at the two poles of Saturn pushes researchers to think that different processes are probably at work at the two poles of the planet. According to Leigh Fletcher, lead author of the study and global scientist at the University of Leicester in England, this could be explained by the asymmetry of the north and south poles of Saturn. Or because the vortex of the North Pole continued to develop after the end of Cassini’s mission in September 2017.
The study of the high-altitude hexagonal vortex of Saturn should help scientists to learn more about atmospheric phenomena, including how lower-level phenomena affect the environment at high altitudes.
The results of the study were published in the journal Nature Communications.