There's a Mighty Maelstrom at Saturn's North Pole
The spinning vortex of Saturn’s north polar storm as imaged by Cassini.NASA/JPL-Caltech/SSI
The incredible vortex of spiraling clouds that churns above Saturn's north pole is seen in all its blood-red glory in this stunning image from NASA's Cassini spacecraft, released today (April 29).
Taking advantage of a new orbital trajectory that puts it high above Saturn's rings and poles, Cassini acquired the near-infrared images used to make this composite back on Nov. 27, 2012. The resulting image is false color -- our eyes aren't sensitive to those particular wavelengths of light -- but still no less amazing.
The intense coloration does serve a purpose besides being pretty. The deep-red rose colors correspond to cloud layers lower in the atmosphere, while emerald-hued clouds are higher up.
Lit by the sun at a low angle (summer is currently on its way to Saturn's northern hemisphere) the towering clouds within the vortex cast strong shadows, heightening the level of detail.
A wider-angle view of the ringed planet's pole looks like this:
False-color image of Saturn’s northern pole as imaged by Cassini.NASA/JPL-Caltech/SSI
(For a more "true-color" view of the same area, click here.)
"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 Caltech. "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."
Much larger than any hurricane ever seen on Earth, the storm over Saturn's north pole is 1,250 miles (2,000 kilometers) wide with wind speeds up to 330 mph (150 meters per second).
Fueled by internal heat and powerful eddies, and with no underlying land masses to affect them, winds on the rapidly-rotating Saturn can reach over 1,100 mph (1,800 km/h). And with nowhere else to go, this polar hurricane will remain at the planet's pole indefinitely... it was likely already there when Cassini arrived in 2004.
Positioned directly over Saturn's north pole, the storm also lies at the heart of a larger and similarly long-lived atmospheric structure called the hexagon, a curiously geometric configuration of jet stream winds.
Nine years at Saturn and Cassini is still amazing us with incredible images.
"One of the most gorgeous sights we have been privileged to see at Saturn, as the arrival of spring to the northern hemisphere has peeled away the darkness of winter, has been the enormous swirling vortex capping its north pole and ringed by Saturn's famed hexagonal jet stream."