Saturn’s Northern Storm
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| Courtesy of NASA/JPL-Caltech/Space Science Institute |
This false-color mosaic from NASA’s Cassini spacecraft shows the tail of Saturn’s huge northern storm. In mid-September 2004, the Cassini spacecraft chronicled a similar, but smaller, storm in the southern hemisphere called the “Dragon Storm.”
The head of this storm is beyond the horizon in this view. Saturn’s atmosphere and its rings are shown here in a false color composite made from 12 images taken in near-infrared light through filters that are sensitive to varying degrees of methane absorption. Red and orange colors in this view indicate clouds that are deep in the atmosphere. Yellow and green colors, most noticeable near the top of the view, indicate intermediate clouds. White and blue indicate high clouds and haze. The rings appear as a thin horizontal line of bright blue because they are outside of the atmosphere and not affected by methane absorption.
The oval in the upper left of this image that appears slightly blue is the same hole in the deep clouds of the planet’s atmosphere that can be seen near the tail in a larger false-color mosaic, PIA14903. The blue color comes from the high haze overlying the hole.
This view looks toward the northern, sunlit side of the rings from just above the ring plane. The shadow of the moon Enceladus is visible on the planet in the lower left of the image.
The images were taken with the Cassini spacecraft wide-angle camera 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.
The images were taken on Jan. 12, 2011, over about one hour at a distance of approximately 684,000 miles (1.1 million kilometers) from Saturn and at a sun-Saturn-spacecraft, or phase, angle of 52 degrees. The images were re-projected to the same viewing geometry, so that scale in this final mosaic is 76 miles (122 kilometers) per pixel.
