Portraits: Saturn and its largest moon

Posing for portraits for NASA's Cassini spacecraft, Saturn and its largest moon, Titan, show spectacular colors in a quartet of images being released today. One image captures the changing hues of Saturn's northern and southern hemispheres as they pass from one season to the next.

A wide-angle view captures Titan passing in front of Saturn, as well as the planet's changing colors. Upon Cassini's arrival at Saturn eight years ago, Saturn's northern winter hemisphere was an azure blue. Now that winter is encroaching on the planet's southern hemisphere and summer on the north, the color scheme is reversing: blue is tinting the southern atmosphere and is fading from the north.

Cassini's visible-light cameras have seen a concentration of yellowish haze in the detached haze layer at the south pole of Titan since at least March 27. Cassini's visual and infrared mapping spectrometer spotted the massing of clouds around the south pole as early as May 22 in infrared wavelengths. After a June 27 flyby of the moon, Cassini released a dramatic image and movie showing the vortex rotating faster than the moon's rotation period. 

Some of these views, such as those of the polar vortex, are only possible because Cassini's newly inclined -- or tilted -- orbits allow more direct viewing of the polar regions of Saturn and its moons.
Scientists are looking forward to seeing more of the same -- new phenomena like Titan's south polar vortex and changes wrought by the passage of time and seasons -- during the remainder of Cassini's mission.