Photos: Monster Storm Rages on Saturn

The head of Saturn's huge northern storm is well established in this view captured early in the storm's development by NASA's Cassini spacecraft in late 2010.

Saturn's atmosphere and its rings are shown here in a false color composite made from three 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.

This view looks toward the southern, unilluminated side of the rings from just below the ringplane.

This series of images from NASA's Cassini spacecraft shows the development of the largest storm seen on the planet since 1990.

This mosaic of images from NASA's Cassini spacecraft shows the trail of a great northern storm on Saturn raging in full force. Image released Jan. 31, 2013.

This image from NASA's Cassini spacecraft reveals the wind patterns within a large vortex that was spawned by a giant northern storm on Saturn. The arrows indicate the local direction of the winds. These data were obtained on Jan. 11, 2011. Image released Jan. 31, 2013.

This mosaic of a giant storm in Saturn's northern hemisphere uses nearly true color filters, but the images were contrast enhanced. The result is a view that increases the visibility of features.

This mosaic covers an area ranging from about 18 degrees north latitude to 47 degrees north latitude. The views stretch the whole longitude range, passing through 360/0 degrees west longitude near the far right of the mosaics.

The images were obtained with the Cassini spacecraft narrow-angle camera on March 6, 2011 over about 11 hours (about a Saturnian day) at a distance of approximately 2 million miles (3.3 million kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 83 degrees.

Saturn's northern storm marches through the planet's atmosphere in the top right of this false-color mosaic from NASA's Cassini spacecraft.

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 along the top edge 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.

This view looks toward the northern, sunlit side of the rings from just above the ringplane.The images were taken on January 11, 2011, over about 50 minutes, at a distance of approximately 569,000 miles (915,000 kilometers) from Saturn.

This set of images from NASA's Cassini mission shows the evolution of a massive thunder-and-lightning storm that circled all the way around Saturn and fizzled when it ran into its own tail. The storm was first detected on Dec. 5, 2010. Image released Jan. 31, 2013.

The largest storm to ravage Saturn in decades started as a small spot seen in this image from NASA's Cassini spacecraft on Dec. 5, 2010 -- the same day Cassini also detected frequent lightning signals.

The storm is visible as a spot on the terminator between night and day in the northern hemisphere. The spot appears slightly brighter than the surrounding clouds in an area about two-thirds of the way north of the equator.

This set of images from NASA's Cassini spacecraft shows cloud patterns in a band around Saturn before a monstrous thunder-and-lightning storm erupted and again after the head of the storm had disappeared. Image released Jan. 31, 2013.

These two natural color views taken 11 hours -- one Saturn day -- apart by NASA's Cassini spacecraft help scientists measure wind speeds in the huge storm seen here in the planet's northern hemisphere.

The images for the view on the left were acquired with the Cassini spacecraft wide-angle camera on Feb. 23, 2011 at a distance of approximately 1.1 million miles (1.8 million kilometers) from Saturn. The images for the view on the right were acquired with the Cassini spacecraft wide-angle camera on Feb. 24, 2011 at a distance of approximately 1.2 million miles (1.9 million kilometers) from Saturn. Image scale is 64 miles (104 kilometers) per pixel in both views.

This mosaic of false-color images from NASA's Cassini spacecraft shows what a giant storm in Saturn's northern hemisphere looked like about a month after it began. Cassini's imaging camera obtained the images that went into this mosaic on Jan. 11, 2011. Image released Jan. 31, 2013.

These false-color mosaics from NASA's Cassini spacecraft chronicle the changing appearance of the huge storm that developed from a small spot in Saturn's northern hemisphere. Here Cassini captures the changes over the short time span of one Saturn day.

Taken about 11 hours apart, these mosaics consist of 84 images each. The top mosaic was taken earlier than the bottom mosaic. Both mosaics were captured on Feb. 26, 2011, and each of the two batches of images was taken over about 4.5 hours.

This storm is the largest and longest-lasting observed on Saturn by either NASA's Voyager or Cassini spacecraft. The storm's active phase ended in June 2011, but, as of October 2011, the turbulent clouds have continued to linger in the atmosphere.

With kaleidoscopic forms and hues, these two false color views from NASA's Cassini spacecraft show the patterns that come and go in the course of one Saturn day within the huge storm in the planet's northern hemisphere.

Taken about 11 hours -- or one Saturn day -- apart, these mosaics consist of 60 images each. The top mosaic was taken on Aug. 17, 2011, while the bottom mosaic was captured on Aug. 18, 2011. Each of the two batches of images was taken over the course of about 3 hours.

This close-up image is a zoomed in and cropped view of the Cassini spacecraft's first view of a storm in Saturn's northern hemisphere that would ultimately grow to be the planet's largest in decades. The storm was first spotted in this image on Dec. 10, 2010.

These two false color views from NASA's Cassini spacecraft show detailed patterns that change during one Saturn day within the huge storm in the planet's northern hemisphere.

Taken about 11 hours -- or one Saturn day -- apart, these mosaics consist of 48 images each. The top mosaic was taken earlier than the bottom mosaic. Both mosaics were captured on Aug. 7, 2011, and each of the two batches of images was taken over about 2.5 hours.

The biggest, most long-lasting Saturnian storm seen by either NASA's Cassini or Voyager spacecraft roils the atmosphere of the gas giant in this nearly-true-color mosaic of Cassini images. The images were obtained with the Cassini spacecraft narrow-angle camera on March 6, 2011 over about 11 hours (about a Saturnian day) at a distance of approximately 2 million miles (3.3 million kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 83 degrees

These red, orange and green clouds (false color) in Saturn's northern hemisphere indicate the tail end of a massive storm that started in December 2010. Even after visible signs of the storm started to fade, infrared measurements continued to reveal powerful effects at work in Saturn's stratosphere.

A vortex that was part of a giant storm on Saturn slowly dissipates over time in this set of false color images from NASA's Cassini spacecraft. This clockwise vortex spun off the bright head of the storm shortly after the thunder-and-lightning storm erupted in early December 2010. Image released Jan. 31, 2013.