PASADENA, Calif. — It’s roil, roil, global turmoil in a newly released movie that shows the motion of high-altitude clouds in the atmosphere of Jupiter.

The brief, seven-frame movie is the first to show how the clouds move on a global scale, thanks to the leisurely perspective on Jupiter that NASA’s Cassini spacecraft currently enjoys. The spacecraft is flying past Jupiter to gain a gravity boost that will help carry it to distant Saturn by 2004.

Cassini imaged the region between Oct. 1 and Oct. 5, capturing an area that neatly straddles the planet's equator from 50 degrees north to 50 degrees south, covering a 100-degree swath of longitude.

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The images that make up the short film were taken at a wavelength that is absorbed by methane, which is present in Jupiter’s lower clouds. Thus, dark areas in the clip are free of high clouds, allowing the camera to spy deep into the atmosphere. Conversely, bright areas represent regions with thick, high clouds that mask the methane below.

Jupiter’s Great Red Spot and equator appear most prominently in the movie, each covered with bright, high-altitude clouds of haze. By means of comparison, NASA has also released a December 1 composite photo (viewable at right as a click-to-enlarge image) that shows the Great Red Spot in color, along with the Jovian moon Io.

Also visible in the movie are bright ovals at mid latitudes in both the northern and southern hemispheres. The ovals, which swirl in a counterclockwise fashion, appear bright because of the presence of high clouds associated with rising gas.

The movie also reveals smaller-scale features in Jupiter’s atmosphere that are of interest to scientists. In the upper left-hand corner of the movie, a number of small clouds appear to circulate counterclockwise around a flattened dark spot, fluctuating in brightness.

Such fluctuations are likely caused by strong vertical motions, which lead to rapid cloud formation, just as is the case with thunderstorms on Earth. On Jupiter, these formations are good candidates for lightning storms.

Cassini will make its closest approach to Jupiter on Dec. 30. It will arrive at Saturn in 2004.