In Full View: Saturn’s Streaming Hexagon
This colorful view from NASA’s Cassini mission is the highest-resolution view of the unique six-sided jet stream at Saturn’s north pole known as “the hexagon.”Image obtained on Dec. 10, 2012 and released Dec. 4, 2013. [See video of Saturn’s bizarre hexagon here
The huge, mysterious hexagon at Saturn’s north pole may finally have an explanation.
The bizarre hexagonal cloud pattern
was first discovered in 1988 by scientists reviewing data from NASA’s Voyager flybys of Saturn in 1980 and 1981, but its existence was not confirmed until NASA’s Cassini spacecraft observed the ringed planet up-close years later.
Saturn Hexagonal Jet Stream Cassini Spacecraft View
Credit: NASA/JPL-Caltech/Space Science Institute
Saturn’s odd hexagonal jet stream swirls in this amazing photo taken by the Cassini spacecraft. Image released Feb. 3, 2014.
Nothing like the hexagon has ever been seen on any other world. The structure, which contains a churning storm at its center, is about 20,000 miles (32,000 kilometers) wide, and thermal images show that it reaches roughly 60 miles (100 km) down into Saturn’s atmosphere.
Scientists have bandied about a number of explanations for the hexagon’s origin. For instance, water swirling inside a bucket can generate whirlpools possessing holes with geometric shapes. However, there is of course no giant bucket on Saturn holding this gargantuan hexagon.
Saturn’s Hexagon: Ornament View
Credit: NASA/JPL-Caltech/Space Science Institute
The globe of Saturn, seen here in natural color, is reminiscent of a holiday ornament in this wide-angle view from NASA’s Cassini spacecraft. The characteristichexagonal shape of Saturn’s northern jet stream, somewhat yellow here, is visible. At the pole lies a Saturnian version of a high-speed hurricane, eye and all. This image was taken on July 22, 2013 and released on Dec. 23. [Read the Full Story Here
Voyager and Cassini did identify many features of this strange hexagon that could help explain how it formed. For example, the points of the hexagon rotate around its center at almost exactly the same rateSaturn rotates on its axis. Moreover, a jet stream air current, much like the ones seen on Earth, flows eastward at up to about 220 mph (360 km/h) on Saturn, on a path that appears to follow the hexagon’s outline.
Now researchers have developed a model they suggest matches the hexagon’s features better than previous attempts.
Hexagon in Silhouette
Credit: NASA/JPL-Caltech/University of Arizona
This still image from an infrared movie from NASA’s Cassini mission shows the churning of the curious six-sided jet stream at Saturn’s north pole known as “the hexagon.” The image was obtained on June 14, 2013 and released Dec. 4, 2013. [See video of Saturn’s bizarre hexagon here
“With a very simple model, we have been able to match many of the observed properties of the hexagon,” study lead author Raúl Morales-Juberías, a planetary scientist at the New Mexico Institute of Mining and Technology, told Space.com.
The scientists ran computer simulations of an eastward jet flowing in a curving path near Saturn’s north pole. Small perturbations in the jet — the kind one might expect from jostling with other air currents — made it meander into a hexagonal shape. Moreover, this simulated hexagon spun around its center at speeds close to that of the real one.
Saturn’s Massive Northern Hurricane
The spinning vortex of Saturn’s north polar storm resembles a deep red rose surrounded by green foliage in this false-color image from NASA’s Cassinispacecraft. The storm’s eye is about 1,250 miles (2,000 kilometers) across with cloud speeds as fast as 330 mph (530 kph).
The scenario that best fits Saturn’s hexagon involves shallow jets at the cloud level, study team members said. Winds below the cloud level apparently help keep the shape of the hexagon sharp and control the rate at which the hexagon drifts.
Different models, such as ones that involve deeper winds or do not take winds lower down into account, do not match Saturn’s hexagon well. For instance, they might result in a six-pointed star, or shapes with more or less than six points, or six pairs of storms arranged in a hexagonal pattern.
Saturn’s North Pole
The north pole of Saturn, in the fresh light of spring, is revealed in this color image from NASA’s Cassini spacecraft.
Morales-Juberías would now like to compare this new research with models from other research teams to see how these findings hold up. He and his colleagues detailed their findings in June in the journal Astrophysical Journal Letters.
Saturn’s North Pole in Psychedelic Color
This spectacular false-color image from NASA’s Cassini mission highlights the storms at Saturn’s north pole.
Spectacular Saturn Storm Photo: Cassini
This spectacular photo of a polar storm on Saturn was taken by NASA’s Cassini spacecraft on Nov. 27, 2012. It is a raw and unprocessed image.
Bizarre Hexagon Spotted on Saturn
Credit: NASA/JPL/University of Arizona
A bizarre six-sided feature encircling the north pole of Saturn near 78 degrees north latitude has been spied by the visual and infrared mapping spectrometer on NASA’s Cassini spacecraft.
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