Moon and Saturn
 Oval-shaped storms as big as countries drift with the winds in the northern hemisphere of Saturn in this recent image from the Cassini spacecraft. To the eye alone, Saturn looks fairly calm. But Cassini's cameras can peer beneath the haze at the top of its atmosphere to see storms and other features. Saturn's high-speed rotation creates bands of clouds that stretch all the way around the planet. Strong winds separate the bands. [NASA/JPL/SSI]
Yet observations by the Cassini spacecraft show that Saturn isn't as calm as it looks. Cassini's instruments can look deep into the clouds, where they see big storm systems with thunderstorms that are thousands of times stronger than those on Earth.
In fact, giant storms encircle both of Saturn's poles. They span thousands of miles, and the winds at their perimeters blast along at more than 300 miles per hour.
The storms are a lot like the hurricanes on Earth. As water from thunderstorms falls deep into Saturn's atmosphere, it releases heat. The heat drives the storms -- just like Earthly hurricanes.
Each storm rotates around a central eye, with a thick wall of clouds around the eye. And a six-sided wall of clouds surrounds the storm at the north pole. This hexagon hasn't changed much over the last four years -- the entire time that Cassini has been watching Saturn.
And you can watch Saturn, too. It looks like a bright golden star a little to the left of the Moon as they rise around 11 o'clock. It keeps company with the Moon as they climb high overhead during the wee hours of the morning.
Script by Damond Benningfield, Copyright 2008
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