As I mentioned previously, Saturn doesn’t get the love some of our other gas giants do. [All hail our friend and lord, Jupiter! Keeping Ogdy at bay… - Ed] Indeed… [new link] But, with the help of Cassini, Saturn does provide some wondrous images. In some of its first sunlit images of Saturn’s north pole, Cassini has looked inside the mysterious hexagon-shaped jet-stream noted here, and spied an enormous hurricane.
In high-resolution pictures and video, scientists see the hurricane’s eye is about 1,250 miles (2,000 kilometers) wide, 20 times larger than the average hurricane eye on Earth. Thin, bright clouds at the outer edge of the hurricane are traveling 330 mph(150 meters per second). The hurricane swirls inside a large, mysterious, six-sided weather pattern known as the hexagon.
“We did a double take when we saw this vortex because it looks so much like a hurricane on Earth,” said Andrew Ingersoll, a Cassini imaging team member at the California Institute of Technology in Pasadena. “But there it is at Saturn, on a much larger scale, and it is somehow getting by on the small amounts of water vapor in Saturn’s hydrogen atmosphere.”
Here’s the video from JPLNews on YouTube
From the associated text
The spinning vortex of Saturn’s north polar storm resembles a deep red rose of giant proportions surrounded by green foliage in this false-color image from NASA’s Cassini spacecraft. Measurements have sized the eye at a staggering 1,250 miles (2,000 kilometers) across with cloud speeds as fast as 330 miles per hour (150 meters per second).
This image is among the first sunlit views of Saturn’s north pole captured by Cassini’s imaging cameras. When the spacecraft arrived in the Saturnian system in 2004, it was northern winter and the north pole was in darkness. Saturn’s north pole was last imaged under sunlight by NASA’s Voyager 2 in 1981; however, the observation geometry did not allow for detailed views of the poles. Consequently, it is not known how long this newly discovered north-polar hurricane has been active.
The images were taken with the Cassini spacecraft narrow-angle camera on Nov. 27, 2012, using a combination of spectral filters sensitive to wavelengths of near-infrared light. The images filtered at 890 nanometers are projected as blue. The images filtered at 728 nanometers are projected as green, and images filtered at 752 nanometers are projected as red. In this scheme, red indicates low clouds and green indicates high ones.
The view was acquired at a distance of approximately 261,000 miles (419,000 kilometers) from Saturn and at a sun-Saturn-spacecraft, or phase, angle of 94 degrees. Image scale is 1 mile (2 kilometers) per pixel.
And a colour image of the north pole of Saturn, in the fresh light of spring. [Image Credit: NASA/JPL-Caltech/SSI]
From the associated text
The north pole of Saturn, in the fresh light of spring, is revealed in this color image from NASA’s Cassini spacecraft. The north pole was previously hidden from the gaze of Cassini’s imaging cameras because it was winter in the northern hemisphere when the spacecraft arrived at the Saturn system in 2004.
A hurricane-like storm circling Saturn’s north pole at about 89 degrees north latitude is inside the famous “hexagon” feature, which scientists think is a wandering jet stream that whips around the north pole at about 220 miles per hour (98 meters per second). It folds into a six-sided shape because the hexagon is a stationary wave that guides the path of the gas in the jet. The hexagon borders occur at about 77 degrees north latitude and the feature is wider than two Earths. Saturn’s rings can be seen at the upper right of the image.
Images with red, green and blue spectral filters were combined to create this natural-color view, which is what the human eye would see if we were there at Saturn. The image here was acquired with the Cassini spacecraft wide-angle camera on Nov. 27, 2012 at a distance of approximately 260,000 miles (418,000 kilometers) from Saturn and at a sun-Saturn-spacecraft, or phase, angle of 96 degrees. Image scale is 18 miles (28.6 kilometers) per pixel.
A false-color version of this image can be seen at PIA14946.
Here’s a short JPLNews video on the hurricane at Saturn’s north pole narrated by Andy Ingersoll, a member of the Cassini orbiter’s imaging team.
And, via the Professor, as Cosmic Log’s Alan Boyle says, “Who knew a monstrous Saturnian hurricanecould look so lovely?“
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