Washington, Oct 14 : New images from NASA's Cassini spacecraft have revealed a giant cyclone at Saturn's north pole, and show that a similarly monstrous cyclone churning at Saturn's south pole is powered by Earth-like storm patterns.
The new-found cyclone at Saturn's north pole is only visible in the near-infrared wavelengths because the north pole is in winter, thus in darkness to visible-light cameras.
At these wavelengths, about seven times greater than light seen by the human eye, the clouds deep inside Saturn's atmosphere are seen in silhouette against the background glow of Saturn's internal heat.
The entire north pole of Saturn is now mapped in detail in infrared, with features as small as 120 kilometers (75 miles) visible in the images.
Time-lapse movies of the clouds circling the north pole show the whirlpool-like cyclone there is rotating at 530 kilometers per hour (325 miles per hour), more than twice as fast as the highest winds measured in cyclonic features on Earth.
This cyclone is surrounded by an odd, honeycombed-shaped hexagon, which itself does not seem to move while the clouds within it whip around at high speeds, also greater than 500 kilometers per hour.
Oddly, neither the fast-moving clouds inside the hexagon nor this new cyclone seem to disrupt the six-sided hexagon.
New Cassini imagery of Saturn's south pole shows complementary aspects of the region through the eyes of two different instruments.
Near-infrared images from the visual and infrared mapping spectrometer instrument show the whole region is pockmarked with storms, while the imaging cameras show close-up details.
Unlike Earth-bound hurricanes, powered by the ocean's heat and water, Saturn's cyclones have no body of water at their bases, yet the eye-walls of Saturn's and Earth's storms look strikingly similar.
Saturn's hurricanes are locked to the planet's poles, whereas terrestrial hurricanes drift across the ocean.
"These are truly massive cyclones, hundreds of times stronger than the most giant hurricanes on Earth," said Kevin Baines, Cassini scientist on the visual and infrared mapping spectrometer at NASA's Jet Propulsion Laboratory, Pasadena, California.
"Dozens of puffy, convectively formed cumulus clouds swirl around both poles, betraying the presence of giant thunderstorms lurking beneath. Thunderstorms are the likely engine for these giant weather systems," he added.
In the south, the new infrared images of the pole, under the daylight conditions of southern summer, show the entire region is marked by hundreds of dark cloud spots.
The clouds, like those at the north pole, are likely a manifestation of convective, thunderstorm-like processes extending some 100 kilometers (62 miles) below the clouds.